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DFID
ANIMAL HEALTH PROGRAMME
Assessment of the impact of zoonotic infections
(bovine tuberculosis and brucellosis) in selected regions of
The Gambia, Senegal, Guinea, and Guinea Bissau - A Scoping study -
Fred Unger and Susanne Münstermann
International Trypanotolerance Centre
Banjul, The Gambia, May 2004
1
List of acronyms and abbreviations
BTB Bovine Tuberculosis
B. abortus Brucella abortus
BQ Black quarter
C. bovis Cysticercus bovis
CIDT Comparative Intradermal Tuberculin Test
Cl. botulinum Clostridia botulinum
CRD Central River Division
DVO District Veterinary Officer
FMD Food and mouth disease
GB Guinea Bissau
GBA Greater Banjul Area
H.S. Haemorrhagic septicaemia
ILRI International Trypanotolerance Centre
LIPS Low input production system
MOPS Market orientated production system
M. bovis Mycobacterium bovis
PH Public health
p.m. post mortem
PRA Participatory Rural Appraisal
PPR Pest de Petite Ruminants
PROCORDEL Program Concerté recherche-développement sur l’élevage en
Afrique de l’Ouest
SR Small ruminants
SSA Sub-Saharan Africa
TB Tuberculosis
VH Veterinary health
WA Weighted average
WAS West African shorthorn
2
List of contents
SUMMARY ..............................................................................................................................6
1. BACKGROUND .........................................................................................................11
2. PURPOSE OF THE STUDY.......................................................................................13
3 PRODUCTION SYSTEMS AND COUNTRY CHARACTERISTICS IN THE STUDY AREA................................................................................................13
3.1 Some country characteristics...................................................................................................16 3.1.1 The Gambia ..................................................................................................................... 16 3.1.2 Guinea Bissau.................................................................................................................. 17 3.1.3 Guinea ............................................................................................................................. 18 3.1.4 Senegal ............................................................................................................................ 19
4. MATERIALS AND METHODS...................................................................................21
4.1 Study period..............................................................................................................................21
4.2 Study area .................................................................................................................................21
4.3 Survey based on Participatory Rural Appraisal (PRA)........................................................24 4.3.1 Team members for PRA sessions..................................................................................... 25 4.3.2 Disease ranking ............................................................................................................... 25
4.4 Survey based on semi-structured questionnaire....................................................................26
4.5 Survey based on serological sampling for brucellosis ...........................................................26
4.6. Data analysis .............................................................................................................................26
5 RESULTS ...................................................................................................................27
5.1 Study population.......................................................................................................................27
5.2 Farmers’ perceptions of animal diseases................................................................................29 5.2.1 Disease importance ranking ............................................................................................ 29
5.2.1.1 Results presented by country ..........................................................................................29 5.2.1.2 Results presented by production system.........................................................................31
5.2.2 Chronic diseases.............................................................................................................. 33 5.2.2.1 Chronic diseases in cattle................................................................................................33 5.2.2.2 Chronic diseases in small ruminants...............................................................................35
5.3 Farmers perception on zoonoses .............................................................................................36 5.3.1 Questionnaire results for zoonoses.................................................................................. 36
5.3.1.1 Results by country ..........................................................................................................36 5.3.1.2 Results by production system .........................................................................................40
5.3.2 Group discussion results for zoonoses ............................................................................ 41
5.4 Specific observations on brucellosis ........................................................................................43 5.4.1 Symptoms of brucellosis ................................................................................................. 43
5.4.1.1 Results by country for cattle ...........................................................................................43 5.4.1.2 Results by country for small ruminants ..........................................................................44
3
5.4.1.3 Results by production system .........................................................................................45 5.4.2 Handling of aborted foetus .............................................................................................. 46
5.4.2.1 Results by country ..........................................................................................................46 5.4.2.2 Results by production system ........................................................................................47
5.4.3 Handling of milk from cows with previous history of abortion or observed hygromas .. 47 5.4.3.1 Results by country ..........................................................................................................47 5.4.3.2 Results by production system .........................................................................................48
5.5 Attitudes to the importance of quality of livestock products................................................49 5.5.1 Observations on meat quality related to animal diseases ............................................... 49 5.5.2 Observations on milk related to animal diseases ............................................................ 51 5.5.3 Handling of milk produced on farms ............................................................................... 53
5.6 Observations on zoonoses by other groups involved.............................................................55 5.6.1 Butchers ........................................................................................................................... 55
5.6.1.1 Butchers’ knowledge of zoonoses ..................................................................................56 5.6.1.2 Zoonotic diseases observed during the last 12 months...................................................57 5.6.1.3 Knowledge of animal diseases which can influence meat quality..................................57 5.6.1.4 Health status of butchers.................................................................................................58
5.6.2 Veterinary health authorities............................................................................................ 59 5.6.2.1 Observations on zoonotic infections in animals .............................................................60 5.6.2.2 Animal diseases observed during the last year ...............................................................60
5.6.3 Public health sector ......................................................................................................... 62 5.6.3.1 Observations of zoonotic infections during the last three years ....................................64 5.6.3.2 Diagnostic capacity of local health centres and hospitals with respect to brucellosis-like
infections and tuberculosis .............................................................................................64 5.6.3.3 Specific knowledge of brucellosis .................................................................................66
5.7 Potential direct and indirect losses due to brucellosis ...........................................................67 5.7.1 General herd parameters................................................................................................. 67 5.7.2 Direct and indirect losses due to brucellosis (abortions and cow sterility) .................... 69
5.8 Serological sampling for brucellosis .......................................................................................70 5.8.1 B. abortus in herd bulk milk samples .............................................................................. 70 5.8.2 B. abortus in man (volunteers) ........................................................................................ 71
5.9 Differences in local perceptions of the impact of zoonoses on livestock and man in relation to present and previous serological findings in cattle .............................................71
5.9.1 Brucellosis ....................................................................................................................... 71 5.9.2 Tuberculosis .................................................................................................................... 74
6 DISCUSSION .............................................................................................................75
7 CONCLUSIONS .........................................................................................................81
8 RECOMMENDATIONS ..............................................................................................82
8.1 Recommendations for the control of Bovine Brucellosis in the countries of this survey.........................................................................................................................................82
8.1.1 Guinea ............................................................................................................................. 82 8.1.2 Guinea Bissau.................................................................................................................. 83 8.1.3 Gambia and Senegal........................................................................................................ 84
8.2 Recommendations for future research ...................................................................................85
9 ACKNOWLEDGEMENT.............................................................................................86
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10 REFERENCES ...........................................................................................................88
11 ANNEX .......................................................................................................................94
11.1 Results of this survey...............................................................................................................94 11.1.1 Annex 1a: Guidelines for PRA sessions.......................................................................... 94 11.1.2 Annex 1b: Tables 1 - 2 and Graphs 1 - 8 ........................................................................ 96
11.2 Results of previous ITC studies on bovine brucellosis and BTB........................................102
LIST OF TABLES Table 1: Number of questionnaires administered per region and involved group............................28 Table 2: Top-five diseases or symptoms in cattle as ranked by farmers´ in terms of importance by
country................................................................................................................................30 Table 3: Top-five diseases or symptoms in SR as ranked by farmers´ in terms of importance
by country...........................................................................................................................31 Table 4: Top-five diseases or symptoms in cattle as ranked by farmers´ in The Gambia in terms of
importance by production system.......................................................................................32 Table 5: Top-five diseases or symptoms in cattle as ranked by farmers´ in Senegal in terms of
importance by production system.......................................................................................32 Table 6: Reports by farmers during group discussions of chronic (long lasting) diseases in cattle .34 Table 7: Consumption patterns (on farm) for meat and milk from chronic sick cattle related to
production system...............................................................................................................35 Table 8: Proportion of farmers by country with knowledge of unpecified zoonotic diseases..........36 Table 9: Numbers of farmers identifying diseases with perceived zoonotic character (first
mentioned disease)..............................................................................................................37 Table 10: Farmers´ ranking of the importance of four given zoonoses by country........................38 Table 11a: Specific knowledge of rabies and clinical observations in animals during the last three
years by country (% of farmers) .....................................................................................38 Table 11b: Specific knowledge of anthrax and clinical observations in animals during the last three
years by country (% of farmers) .....................................................................................39 Table 11c: Specific knowledge of BTB and clinical observations in animals during the last three
years by country (% of farmers) .....................................................................................39 Table 11d: Specific knowledge of bovine brucellosis and clinical observations in animals during
the last three years by country (% of farmers)................................................................40 Table 12: Clinical signs potentially indicative of brucellosis infection observed by farmers in
their cattle (proportion of farmers by country) ...............................................................44 Table 13: Clinical signs potentially indicative of brucellosis infection observed by farmers in
their small ruminants (proportion of farmers by country) .............................................45 Table 14: Abortions observed by farmers in their cattle or small ruminants (proportion of farmers
by production system and country).................................................................................45 Table 15: Ways of handling aborted foetuses by country (proportion of farmers interviewed).....46 Table 16: Ways of handling aborted foetuses by production system and country (proportion of
farmers interviewed).......................................................................................................47 Table 17 : Farmers ways of dealing with milk from cows with a history of abortion or observed
hygroma by country (proportion of farmers)..................................................................48 Table 18: Farmers ways of dealing with milk from cows with a history of abortion or observed
hygroma by production system and country (proportion of farmers).............................48 Table 19: Processing of milk produced on-farm presented by country (% of farmers)..................53 Table 20: Processing of milk produced on-farm presented by production system and country
(% of farmers).................................................................................................................54 Table 21: General information on aspects related to slaughter and sale of cattle and small
ruminants (number per butcher per week)......................................................................55 Table 22: Proportion of butchers with knowledge of unspecified zoonotic diseases by country ...56
5
Table 23: List of suspected diseases with zoonotic importance observed by individual butchers during slaughter (last 12 months) ...................................................................................57
Table 24: Butchers’ knowledge of symptoms and associated diseases which can influence meat quality .............................................................................................................................58
Table 25: Observations on health status of butchers ......................................................................59 Table 26: Information on the interviewed VH respondents............................................................59 Table 27: Zoonotic infection in animals and humans reported by VH respondents in the study
districts during the last 3 years .......................................................................................60 Table 28: Diseases or symptoms in cattle ranked by DVOs according to their importance over the
last 12 months by country...............................................................................................61 Table 29: Diseases or symptoms in SR ranked by DVOs according to their importance over the
last 12 months by country...............................................................................................61 Table 30: Numbers of interviewed public health facilities in the study districts by country..........62 Table 31: Exchange of information between PH and VH authorities.............................................63 Table 32: Reports of zoonoses in humans over the last three years in the health centres and
hospitals visited ..............................................................................................................64 Table 33: Selected information on diagnostic procedures and prevalences related to flu-like
infections and TB among patients that visited the health centre of this survey during the last year by country...................................................................................................65
Table 34: Knowledge of brucellosis symptoms in man and diagnostic procedures (number of hospitals or health centres by country) ...........................................................................66
Table 35: Mean herd sizes and proportion of bulls, cows, heifers and calves based on questionnaires by country...............................................................................................67
Table 36: Cattle breeds in the study population (number of farms) ...............................................68 Table 37: Selected herd fertility parameters ...................................................................................69 Table 38: Serological results for B. abortus for herd bulk milk samples .......................................70 Table 39: Respondents’ perceptions of brucellosis and serological findings by country ...............72 Table 40: Respondents’ perceptions of BTB and serological findings by country.........................74
6
Summary Introduction
In order to evaluate the direct and indirect impact of brucellosis and bovine
tuberculosis and other zoonoses on livestock and human health a scoping study was
commissioned by DFID to ITC. The study was carried out in selected areas of The
Gambia, Senegal, Guinea Bissau and Guinea Conakry during the period of March to
August 2003. This survey expands on work already done at ITC investigating the
distribution and prevalence of both diseases in different locations in all four
countries, which focussed primarily on updating the limited existing information on
the animal health aspects related to these diseases in the four countries.
Materials and methods
The study was carried out in form of a Participatory Rural Appraisal (PRA). The
PRA took place in 2 districts of The Gambia (Central River Division south, CRD and
Greater Banjul Area, GBA), Senegal (Kaolack and Fatick), Guinea (Dubréka and
Coyah) and in one district (Bafata) of Guinea Bissau. In each district three (GBA) up
to four (all other) half-day PRA sessions in different, randomly selected locations
were carried out. For each PRA session 10-24 respondents (on average 14) were
selected consisting of farmers, herdsmen and milk vendors from one and up to 4
surrounding villages. The study population consisted in the Gambia of 115, in
Senegal of 116, in Guinea of 100 and in Guinea Bissau of 58 respondents. Overall,
73% of the respondents were males and 27% females. The respondents were
composed of 47% farmers, 26% herders and 27% milk vendors. The PRA team was
composed of one national expert and two enumerators. One ITC scientist and a local
veterinary officer joined the sessions as observers.
Besides gaining information during the PRA, a semi-structured questionnaire was
applied in each district to farmers (n= 20), the Veterinary health authorities, local
butchers/meat inspectors (up to five) and Public health authorities. Key issues such as
observations on diseases transmissible to humans, observations after slaughter or at
post mortem inspection and awareness of diseases that affect the quantity and quality
of milk and meat were considered in these questionnaires.
7
To find correlations with results of already completed prevalence studies on
brucellosis, bulk milk samples from each village/farm participating in the study were
collected and tested for B. abortus. In addition serological sampling in man (farmers,
veterinarians and herders) was carried out in Dubréka, a district known to have a
high prevalence for brucellosis.
Results
• Results for disease ranking
Results from disease ranking for cattle differed between the countries, with high
ranks for Haemorrhagic Septicaemia (H.S.) and the “diarrhoea complex” in all four
countries. Reports on infections with zoonotic character varied widely between the
four countries. Anthrax was number two in Guinea. Clinical hygromas (indicating
brucellosis) were only mentioned by farmers in Guinea Bissau and Guinea and given
rank number five.. In small ruminants PPR was the highest ranked disease in three of
the four countries. In The Gambia, where unspecific diarrhoea and Pasteurellosis
were ranked higher, PPR was number three among the “top five”. Anthrax was only
among the top-five list in Guinea Bissau.
• Observations on chronic diseases
With regional variations brucellosis (only reported for Guinea and Guinea Bissau)
and trypanosomosis were the most frequently observed chronic diseases in cattle.
Chronic specific diseases in SR (n= 9) were less frequently reported than in cattle
(35). Mange (n= 3) was recorded most often.
• Farmers perceptions on zoonoses
Farmers’ knowledge of zoonoses differed between the countries but was not related
to the production system. Among four given zoonoses (rabies, anthrax, BTB and
brucellosis) rabies was ranked highest by farmers in Guinea, Guinea Bissau and
Senegal, followed by brucellosis in Guinea Bissau, Guinea and Senegal. The highest
level of knowledge based on interviews and group discussions can be attested to
farmers from Guinea Bissau. This includes the knowledge of symptoms and, with the
exception of anthrax, also the transmission route and how to prevent transmission.
Clinical cases of anthrax and brucellosis in cattle were more frequently reported by
farmers in Guinea Bissau than in the other three countries. In addition, brucellosis
was more often observed by farmers in Guinea than in Senegal and The Gambia,
8
where infections were not common. Results from group discussions on zoonoses
showed that in particular the knowledge of the public health importance of anthrax
was poor. The majority of participants in The Gambia, Senegal and Guinea indicated
that meat from such animals is consumed after proper cooking or application of
traditional treatment. Results of group discussions in Guinea indicate that cattle with
hygroma are often not considered to be sick and milk is consumed without heat
treatment.
• Observations related to abortions
The number of reported cases of abortions and hygromas in cattle were significantly
higher in Guinea and Guinea Bissau. Abortions in SR were not influenced by country
or production systems. The ways of handling of aborted foetuses and of milk from
cows with abortion history or observed hygroma differed also between countries but
not between production systems.
• Observations related to meat and milk quality
The main indicators for reduced meat quality mentioned by farmers in all four
countries were bad smell, pale colour and higher water content. The handling of such
meat and specific knowledge of the causing agent varies widely between the
countries. Highest level of knowledge was found in Guinea Bissau followed by
Guinea. Conversely, knowledge in The Gambia and Senegal was very limited.
Accordingly meat of bad quality was also handled differently, i.e. usually consumed
in Senegal and The Gambia while often discarded by farmers in Guinea Bissau.
• Observations related to milk quality and processing
During all group discussions it was agreed, that milk is a good source of energy and
healthy but certain animal diseases can affect the quality of the product and may even
transmit diseases to man. Changes in milk quality were generally characterized by
higher water content, clotting and faster fermentation. Milk of reduced quality is
usually not used for home consumption. Specific knowledge of the causative agent
and how to prevent transmission differed between the regions and was found highest
in Guinea Bissau. Milk in the region is usually consumed without treatment with the
exception of Guinea Bissau.. Farmers and milk vendors clearly believe that milk, if
boiled once, will not ferment, therefore milk is usually not heat treated because of
customers’ preference for fermented milk. The use of starter cultures for fermentation
after heating is not known. Moreover, a good number of farmers in Senegal and The
9
Gambia still believe that heating of milk may significantly reduce the milk yield of
the producing cow. This traditional believes might limit the willingness of these
farmers to accept pasteurisation as measure to prevent the transmission of zoonoses.
• Observations on zoonoses by butchers
The majority of butchers knew of at least one zoonotic infection. Their awareness of
a second and third zoonosis was clearly reduced. The zoonoses most frequently
observed by butchers were brucellosis, followed by anthrax. A higher frequency of
this infection was reported for Guinea Bissau and Guinea.
The execution of regular health checks of butchers varied between the countries.
However, none of the check ups was documented by health certificates.
• Observations by veterinary health authorities
The most important zoonosis in respect to mortality in man was rabies followed by
anthrax. The number of reported cases of rabies in animals (all of them dogs) was
very similar in the four countries. Conversely more cases of anthrax and brucellosis
were observed in Guinea and Guinea Bissau. The results for disease importance
ranking obtained from veterinary authorities were consistent with those obtained
from farmers
• Observations on zoonoses by public health authorities
Rabies was the highest ranked zoonosis by public health authorities followed by
Salmonella infections. Patients with “brucellosis or flu -like” infections (fever and
back/joint pain) are tested for malaria if laboratory facilities are available. If not,
malaria treatment is administered symptomatically without differential diagnosis, e.g.
for brucellosis. Knowledge of personnel on brucellosis (symptoms, transmission etc.)
was very poor, laboratory tests were not performed in any of the locations visited.
Strain identification for M. bovis in patients with symptoms of TB was not carried out
in the health centres/hospitals visited in Guinea Bissau and Senegal and rarely
undertaken in The Gambia and Guinea.
• Potential losses due to brucellosis
The number of cattle herds with reports on infertile cows or abortions was higher in
Guinea and Guinea Bissau than in Senegal and The Gambia.
10
• Results of serological sampling for brucellosis
B. abortus herd prevalence in bulk herd milk was significantly higher in Guinea and
Guinea Bissau.
Seven out of 20 volunteers tested positive for brucellosis in a high prevalence area for
cattle (Dubréka, Guinea) .
• Differences in local perception in relation to present and previous serological
findings in cattle
Differences observed in perception of farmers and other risk groups on brucellosis
(i.e. knowledge and results of disease importance ranking) were in agreement with
serological results for brucellosis in cattle. Brucellosis was ranked higher by farmers
and veterinarians in the high-risk areas for cattle.
The absence of BTB infection in cattle was confirmed by a general low importance
assigned to this disease by farmers and veterinary health authorities (i.e. it was not
considered as an important disease in the disease ranking).
11
1. BACKGROUND
The expansion of poverty and food insecurity is a cause of major concern in sub-
Saharan Africa (SSA). It is estimated that between 40 to 45% of the African
continent’s 730 million people live in absolute poverty with 30% classified as
extremely poor. West Africa has the highest population growth (3% p.a.) and
urbanisation (6 % p.a.) rates in SSA and one of the highest in the world. By 2050, the
human density of much of West Africa will be similar to present day Nigeria (114
persons/sq km). People’s attempts to secure livelihoods include diversification of
income with a significant increase in the share of the overall household income
coming from livestock production. In general, the livestock sector is intensifying in
response to population and urbanisation increase.
In rural areas, but also in peri-urban livestock production centres, a close relationship
between the people and their animals exists, often coupled with very poor hygienic
conditions. Livestock diseases are controlled only to a limited extent as veterinary
services are defunct and drugs neither readily available nor easily affordable for the
rural and urban poor farmers. Under these circumstances, zoonotic diseases, easily
transmissible from livestock to man and, in the case of tuberculosis also vice-versa,
can play an important role as a contributing factor to poor human health and poverty.
In a recent study commissioned by DFID on prioritising animal health research for
poverty reduction (PERRY et al, 2002), a strong link between poor human health and
low income and zoonotic diseases was stated. Zoonoses can be fatal and disabling
diseases, the prevention of which is usually through control in animals. For this
reason, their control is often left to veterinary services, with human health services
showing only a limited interest or awareness of them. For two classical animal
diseases transmissible to men through infection by contact or consumption of
contaminated animal products, brucellosis (B. abortus and B. melitensis) and
tuberculosis (M. bovis), farmers, herders and butchers have been considered to be the
main groups at risk (ADAMS & MAEGRAITH, 1984). A key risk factor is the
widespread consumption of raw milk in West Africa; which earlier studies at ITC
have shown to be highly contaminated with pathogens that pose a public health risk
to the consumer (HEMPEN et al., 2002, UNGER et al. 2003).
12
Human brucellosis is known as a disease presenting a variety of symptoms, affecting
multiple systems and causing different forms of localised infection. It is characterised
by a febrile reaction and usually associated with enlarged spleen (splenomegalie) and
osteoarticular manifestations (BATHKE, 1987; SEWELL and BROCKLESBY
1990). Further complications are hepatitis, endocarditis, orchitis and meningo-
encephalitis (BATHKE, 1987; DJORDJEVIC, et. al 2003; MASOURIDOU et. al
2003). The classical signs (fever and back/joint pain) are therefore easily confused
with other more common ailments, e.g. malaria and hence often wrongly treated.
These diagnostic difficulties are characteristic for developing countries since specific
tests for brucellosis are usually not available. Tuberculosis comes in the wake of
poverty, war, and immunosuppressive diseases, such as HIV and is on the increase in
most developing countries. In sub-Saharan Africa nearly 2 million TB cases per year
occur and the Genus Mycobacteria has pathogenetic and zoonotic importance
(DABORN et al., 1996). The presence of both diseases in livestock therefore
represents a significant public health risk.
In recent work to establish the geographic distribution and prevalence of both
infections in cattle carried out by ITC (2000 – 2003), various surveys were carried
out in The Gambia, Guinea, Guinea Bissau and Senegal. Brucellosis was diagnosed
in cattle with high variability in the prevalences between different locations within
and between countries. To be more specific, herd prevalences for bovine brucellosis
as high as 61 - 100 % were reported for selected districts in Guinea Bissau and
Guinea whereas in The Gambia and Senegal infections are not common. In contrast
to this, for bovine tuberculosis an unexpected absence of the infection was reported
for all four countries.
These studies focussed primarily on updating the lack of information on the animal
health aspects of brucellosis and tuberculosis in these four countries. In order to fully
understand the impact and importance of these diseases on livestock and people, the
perception of livestock owners and other people in close contact with animals of the
human health aspect needs also to be investigated in order to complement the
information obtained in livestock. Furthermore, information on the economic
13
importance (direct and indirect losses) of zoonotic diseases in livestock is required.
The latter investigations have rarely been addressed in these countries in the past.
It was therefore proposed to carry out a scoping study on the importance of those
zoonotic diseases for people in livestock environments.
2. PURPOSE OF THE STUDY This study was undertaken to evaluate the direct and indirect impact of zoonoses,
with special emphasis on brucellosis and bovine tuberculosis on livestock and human
health in selected areas of The Gambia, Senegal, Guinea Bissau and Guinea Conakry.
The study expands on work already done at ITC investigating the prevalence of both
diseases in different locations in all four countries.
3 PRODUCTION SYSTEMS AND COUNTRY CHARACTERISTICS IN THE STUDY AREA
In the study region two livestock production systems have been identified:: the
predominant low-input system and the Market-oriented system.
The low-input production system (LIPS) operates at subsistence or semi-subsistence
level with farmers growing crops and keeping livestock. They are smallholder
farmers who rely mainly on family labour inputs for cropping and livestock related
activities. Because of the scarcity of resources, farmers in LIPS adopt a risk aversion
strategy which entails limited use of externally purchased inputs that in turn is not
conducive to adoption of new technologies. Livestock is kept for multiple objectives:
subsistence (milk, milk products), sales or exchange, inputs to agriculture (power,
manure), transportation and insurance against crop failure.
The study region is characterised by large areas of medium to high livestock disease
risk due to ecto- and endoparasites, vector- and vector borne diseases. LIPS farmers
consequently use indigenous breeds that are adapted to the feeding, health and
climatic environment, but that have limitations in their productivity.
14
Traditional N’Dama herd in Keneba, The Gambia
LIPS is also characterised by an extensive land use system, animals are fed on natural
pastures and crop residues, with feed supplementation limited to selected groups of
animals during the dry season. Consequently body weight and milk yield decline
during the long dry seasons (particularly in The Gambia and Senegal) to such low
productivity levels that leave limited surplus for marketing.
The vast majority of poor farmers in the study region are found in LIPS. The farmers
are unlikely to engage in innovative production processes in the absence of
infrastructure, easy access to markets and high costs of transportation. However,
LIPS has proven to be dynamic also and respond to new challenges like increased
demand for livestock products. For instance, farmers have changed species
composition due to drought and they are moving to more intensified and integrated
mixed farming systems. (Fall, 2003).
The LIPS is predominant in The Gambia, Guinea Bissau, Guinea and in large parts of
Senegal. It is estimated that 95% of the milk production in this region is produced by
the LIPS (Mbogoh, 1984).
15
Traditional way of milking N’Dama herd in Guinea
A transition process towards intensification has taken place in those areas where
policies are conducive, inputs available and the agro-ecological environment suitable.
It is shown in Nicholson et al. (1999) that West Africa as a region has not only one of
the highest urbanisation and population growth rates, but also harbours the emerging
markets in the coastal cities (Dreschel et al., 1998) that will make the region a major
consumption centre of livestock products in general and dairy products in particular.
This transition to the market-oriented production (MOPS) has often been induced by
urbanisation and the establishment of peri-urban integrated agricultural enterprises.
The systems have developed prominently in the Greater Banjul Area, peri-urban
Dakar, the Nieyes and in the Bassin Arachidier of Senegal and have been studied in
the framework of PROCORDEL (Somda et al., 2003, Somda et al, 2004, Dia et al,
2004)
16
F1 crossbred (Holstein Frisian x N’Dama) with dam in Greater Banjul
Area, The Gambia
The MOPS is geared towards income generation and the maximization of profit. It
entails the introduction of new breeds (cross-bred or purebreds), feed
supplementation, resource inputs such as labour, drugs, feeds. The system is usually
established near marketing structures, existing infrastructure and service providers.
Management strategies need to take into consideration the major challenges:
provision of animal feeds in sufficient quantities year round, processing and
conservation of products (meat and milk) and marketing of products. (Akinbamijo,
2003).
3.1 Some country characteristics
3.1.1 The Gambia
The Gambia, with 11,300 km2 one of the smallest African countries, is completely
surrounded by Senegal, except for the Western Coast line. It has a population of 1,36
Million with 90% Muslim and 9% Christian. It is administratively divided in 5
Divisions and Banjul city. English is the official language, but Mandinka, Wolof and
Fula are widely spoken. Population density is one of the highest in West Africa and
can be compared with Nigeria. The drift to move to growing urban centres is
increasing with presently 40% of the population living in towns. Agriculture
17
contributes 23% to the GDP (1997 estimates) with the main products groundnuts,
millet, sorghum, rice, corn, cassava and palm kernels.
A mixed, crop-livestock farming system is practised throughout the country. The
pattern of rural settlement in The Gambia is described by villages surrounded by
areas of regularly cultivated fields and fallows with, at increasing ranges, long-term
fallows merging into woodland. The cattle population is estimated at 360,000, sheep
at 190,000, goats at 265,000, equines at 51,000 (livestock census, 1993). More than
90% of ruminants in The Gambia are trypanotolerant breeds, namely N’Dama cattle,
Djallonke sheep and West African Dwarf goats. The recent introduction of cross-bred
cattle for the evolving dairy sector is limited to the Greater Banjul Area. The climate
is characterised by a uni-modal rainfall pattern with a long dry season (November to
June). Characteristics of the livestock sector, principal constraints and counter
strategies are well described by Snow in Bourn et al., 2001.
3.1.2 Guinea Bissau
Guinea Bissau covers an area of 36,120 km2, is neighbour to Senegal in the north and
Guinea in the south and east and the Atlantic coast line in the west. It is a low-lying
coastal region of swamps, rain forests, and mangrove, coastal wetlands, with about 25
islands off the coast. The Bijagos archipelago extends 48 km out to sea. The
population is estimated at 1,38 Mill with a growth rate of 2% and 45% Muslims, 5%
Christians and 50% animists. The official language is Portuguese, but Creole is the
language spoken most widely. The country is administratively divided into nine
regions where the population is unevenly distributed. Likewise, the regional density
of the livestock population and specifically cattle is unequal. The Eastern zone
(regions of Bafata and Gabu) has the highest livestock density accounting for 74% of
cattle (MDRA/DGP, 1991). The Northern zone (regions of Cacheu and Oio) follows
the east in terms of livestock numbers, particularly the Oio region with 13% of cattle.
Cattle belong exclusively to the N’Dama breed (FAO, 1980) and are extensively
managed in relation with the socio-economic background of the livestock owners
(Gonçalves, 1995).
18
N’Dama herd at watering point and nearby rice fields in Guinea Bissau
Recent political developments have seen a coup d’état in September 2003 by General
Correia Seabra who later handed over to an interim government led by President
Henrique Rosa. Legislative elections took place in March 2004 and a new
government is expected to be formed in the coming weeks. Presidential elections are
scheduled to take place early 2005. International disputes exist over the separatist war
in Senegal’s Casamance region which results in refugees and cross-border raids, arms
smuggling and other illegal activities, and political instability in Guinea- Bissau.
3.1.3 Guinea
Guinea covers an area of 245,857 km2, is bordered by Guinea-Bissau, Senegal, Mali,
Côte D’Ivore, Liberia and Sierra Leone and has a coast line in the west. The country
consists of a coastal plain, a mountainous region, a savannah interior and forest areas
in the Guinea Highlands with the highest peak of Mount Nimba (1,752 m).It has a
population of 9,25 Million with a relatively low density (19 inhabitants/km2 as
compared to 122/km2 in The Gambia). The growth rate is 2.4% and religion is 85%
Muslim, 8% Christian and 7% animists. Official language is French, but Malinké,
Susu and Fulani are widely spoken.
The country possesses enormous agricultural potential, which varies according to the
four natural agro-ecological zones: Guinée Maritime, Moyenne Guinée, Haute
Guinée and Guinée Forestière. Livestock numbers are 2,5 Mill cattle, 1,5 Mill small
ruminants, 55,000 pigs and 9 Mill poultry (livestock census 1995).. The livestock
19
sector contributes 16% to the agricultural segment of the GDP. The predominant
dairy cattle breed is the N’Dama, which is managed under the low-input system.
However, few crosses (N’Dama x zebu cattle) are found in Haute Guinea. The
regional distribution of cattle from the census conducted in 1995, is as follows:
Maritime (17%), Moyenne (41%), Haute (34%) and Forestière (8%). The Haute
Guinea thus represents the second most important region in terms of livestock
production. Furthermore, several projects, including the ITC led PROCORDEL, are
being implemented with a dairy component and the introduction of crossbreds.
International disputes arise over domestic fighting among disparate rebel groups in
Guinea, Liberia, and Sierra Leone. They have created skirmishes, deaths and refugees
in border areas.
Nature’s beauty after the first rains in Guinea
3.1.4 Senegal
Senegal covers an area of 196,190 km2 and is bordered by Mauritania in the north,
Mali in the east, Guinea and Guinea Bissau in the south and it encloses The Gambia.
The Atlantic coast line forms the western limit. It has a population of 10,59 Mill with
94% Muslim and 5% Christian. The official language is French, Wolof is widely
spoken, other languages are Pular, Serr, Joal, Malinke and Soninke. Agriculture,
which employs more than half the working population, represents 20% of GDP.
Fishing is the country’s primary source of income. Exports are concentrated in the
areas of groundnuts, fishing, tourism and phosphates. The country has a per capita
20
GSP of $459. According to recent surveys, 65% of households consider themselves
poor. (The Courier, 2003). The Casamance conflict is still not fully resolved.
The subdivision of the country into ecological zones relates well to the distribution of
livestock species. The trypanosusceptible Zebu, Sahelian sheep and goats and horses
occupy the Sahelian region, devoid of tsetse, while the south is inhabited mainly by
trypanotolerant N’Dama cattle, Djallonké sheep and dwarf goats and donkeys.
Diakore cattle in Senegal
The sudano-sahelian and north Sudan zones (middle part of the country) have mixed
populations including the Diakore (Zebu x N’Dama cross), which has an intermediate
level of trypanotolerance. The Diakore is a popular draught animal in this region
because it is larger than the N’Dama. The southern soudanian and north Guinean
vegetation zones (Casamance region) are the most important areas of Senegal for
rearing trypanotolerant N’Dama cattle.
At the national level, a period of stable cattle population is seen in the 1980s
probably associated with droughts that occurred during this period. There is however
a trend of a steady increase since the early 1990s. This trend is also seen in the Kolda
and Ziguinchor regions where the majority of trypanotolerant livestock are found.
Three main livestock production systems are described in Senegal. These are (1) the
pastoral system in the Sahel zone with limited rainfall (300-500mm) and therefore
scarce feed and water resources that drive people and livestock to great mobility
21
according to seasons, (2) the peri-urban production system in the Niayes area with
appr. 1000 exotic dairy cattle and in the surroundings of large cities like Kaolack and
Fatick where crossbred dairy cattle have been introduced since the mid 1990s and (3)
the agro-pastoral system with the integration of crop and livestock enterprises.
4. MATERIALS AND METHODS
4.1 Study period
The study was carried out in form of a Participatory Rural Appraisal (PRA) for a
period of 6 months, starting in March 2003. March 2003 was considered as the
Preparation Period for the main study. During this period the national PRA teams,
local authorities, villages and all target groups were identified and sensitised for the
study. The PRA sessions were carried out in April and May in the chosen districts of
The Gambia and Senegal, in June in Guinea and in July in Guinea Bissau.
4.2 Study area
The PRA took place in two districts of The Gambia, Senegal, Guinea and one district
of Guinea Bissau. All chosen districts are known for their high cattle density.
Another criterion for the selection of a district was the involvement in previous ITC
disease prevalence studies on bovine tuberculosis and brucellosis, since useful
background information was already available. For Senegal and The Gambia the
locations represented also different production systems (low input and market-
orientated systems).
In The Gambia the Central River Division south (CRD) and the Greater Banjul Area
(GBA) were selected. The CRD is a rural area and located in the eastern part of The
Gambia. The distance to Banjul is around 300 km. The cattle population consists of
trypanotolerant N´Dama kept on natural pasture under traditional husbandry. The
GBA is a peri-urban area located around Banjul, the capital of The Gambia. The area
is characterised by its current transition from the low-input to the market-orientated
system. The cattle population consists of N´Dama and few crossbred cattle which
22
where recently introduced by ITC. Milk is usually sold to markets in Banjul and the
GBA.
Map of Senegal and The Gambia
In Senegal the districts of Kaolack and Fatick were identified, located in the Bassin
Arachidier (groundnut production basin) southwest of Dakar. The distance to Dakar
is 220 km from Kaolack and 190 km from Fatick. Programmes for intensification of
the existing livestock system are already on-going in the Bassin Arachidier. The
cattle population consists mainly of Zebu type cattle and crossbreds. The proportion
of crossbreds is continuously increasing due to a national artificial insemination
programme.
In Guinea the Districts of Dubréka and Coyah were selected. Dubréka and Coyah are
rural areas. Coyah District is located in the close vicinity of Conakry; the District
capital is 60km away from Conakry. Dubréka District is also situated close to
Conakry. The distance from Dubréka town to Conakry is around 70 km. Milk
produced in the Dubréka and Coyah District is therefore sold also at Conakry
markets. The cattle population consists of pure N´Dama kept on natural pasture under
traditional husbandry. The majority of cattle herds in both districts are on
transhumance during March to June and thereafter move to communal pastures.
23
Map of Guinea
The district of Bafata was selected in Guinea Bissau which is situated in the centre of
Guinea Bissau, bordering Guinea. The distance from Bafata to Bissau is 120 km.
Milk produced in Bafata is sold also at Bissau markets. Bafata holds 40% of the cattle
population of the country and the predominant breed is the N´Dama.
24
Map of Guinea Bissau
4.3 Survey based on Participatory Rural Appraisal (PRA)
Four half day PRA sessions were held in all selected districts, except for the GBA,
were only three sessions were carried out. In total 27 PRA sessions formed the basis
for this study. Sessions were set to be attended by a minimum of 10 and a maximum
of 15 people with 5 to 8 farmers (owners of cattle and small ruminants), 2 to 4
herders (being family members or labourers often paid with milk) and 2 to 4 milk
vendors as participants. Four to 12 villages in each district were randomly chosen by
the District Veterinary Officers (DVO). Hence, 40 to 60 respondents were expected
per district.
Before performing a PRA exercise in a selected location, the village chief was
identified by the DVO, the aims of the study were explained and permission was
sought to carry out the study in the village. The participants from each village were
chosen by the DVO, often in agreement with the local chief, on the basis of
willingness to participate.
25
The PRAs were carried out as group discussions. However, for specific questions,
quantification of group answers was achieved by randomly selecting five individuals
amongst the group of farmers.
The structure of the PRA sessions is listed in Annex 1a.
PRA during the rain in Guinea Bissau and in the open in Guinea 4.3.1 Team members for PRA sessions
The PRA team consisted of 6 individuals, with a variety of skills encompassing
veterinary knowledge, PRA experience, local knowledge of the area and livestock
systems, and fluency in the local languages, and was led by a national PRA expert.
More specifically the team consisted of a PRA expert, 2 enumerators (one of them
socio-economist), the project co-ordinator, the local DVO and one translator. In The
Gambia, Guinea and Guinea Bissau a national PRA team was recruited for the study,
while in Senegal the team consisted of 2 Gambian and one Senegalese enumerator.
4.3.2 Disease ranking
This method was used to obtain perceptions about the differences in disease
importance ranking within and between the countries. In a first step all clinical
symptoms observed by respondents during the last 12 months were recorded. These
clinical symptoms were then related to specific diseases whenever possible. Five
26
farmers (owners of cattle and of small ruminants) were randomly selected among the
group and asked to rank the 5 most important diseases.
4.4 Survey based on semi-structured questionnaire
In addition to the information obtained during the PRA, a semi-structured
questionnaire was administered in each district to randomly selected farmers (n= 20),
Veterinary health authorities, local butchers/meat inspectors (up to five) and Public
health authorities. Key issues like the reproduction status of herds, observations on
diseases transmissible to humans, observations after slaughter or in post mortem and
awareness of diseases that affect the quality and quantity of milk and meat were
considered in these questionnaires.
4.5 Survey based on serological sampling for brucellosis
To find correlations with results of previous prevalence studies on brucellosis, bulk
milk samples from the majority of farms participating in the study were collected and
tested for the presence of B. abortus antibodies using Milk ELISA (Bommeli®).
In addition, to obtain some base line information on brucellosis in man in a known
high risk area for cattle, serological sampling in potential risk groups (farmers,
veterinarians and herders) was carried out in Dubréka (Guinea). According to the
recommendation of the German Reference Laboratory for brucellosis in Berlin these
sera were tested for B. abortus antibodies using Rose Bengal Plate Test followed by
Complement Fixation Test.
4.6. Data analysis
For entry of data, descriptive and quantitative analysis and for graphical presentation
Microsoft Excel, Statgraphics Plus and EPI-Info 5.2 software was used. For
comparison of means simple t-test was applied. To find likely associations between
observations (e.g. abortion occurrence and management) Yates-corrected chi-square
test or Fisher exact test were performed. Significantly differences were expressed as
27
differences between categories marked with different superscripts. The level of
significance is given separate.
5 RESULTS
5.1 Study population
A total of 389 people participated in the PRA sessions, composed of 115 in the
Gambia, 116 in Senegal, 100 in Guinea and 58 participants in Guinea Bissau. The
average number of participants in each PRA session was 14.4 (13.19,15.61).
On average, in each PRA session per location 64.9 to 82.1% (overall mean 72.6%)
were male respondents and 17.5 to 35.1% (overall mean: 27.4%) were females. The
highest proportion of women was found in Dubréka, Guinea (35.1%), the lowest
during group discussions in the LIPS in the Bassin Arachidier of Senegal (17.9%). In
general the gender distribution was quite homogenous for each district and country
(Graph 1).
Graph 1: Gender distribution during group discussion by region and country
The respondents were composed of 39.7 to 54.8% (overall mean: 47.1%) farmers,
18.7 to 37.9% herders (overall mean: 25.9%) and 19.3 to 33.3% milk vendors
(overall mean: 27.0%). The specific distributions for each region are presented in
0%10%20%30%40%50%60%70%80%90%
100%
GBA(MOS)
CRD(LIS)
MOS LIS Dubreka Coyah Bafata
The Gambia Senegal (BassinArachidier)
Guinea GuineaBissau
Overall
male female
28
Graph 2. The proportion of herders was slightly lower in both districts of Guinea
whereas the proportion of milk vendors was a bit higher.
Graph 2: Composition of respondents in group discussions by region and country
The number of respondents in the semi-structured questionnaires is summarized in
Table 1. The reduced amount of farmers selected for The Gambia results from the
limited number of farmers representing the market-orientated system in the GBA (n=
15).
Table 1: Number of questionnaires administered per region and involved group
Farmers Veterinary health
authorities
Public health authorities
Butchers Total
The Gambia (GBA and CRD)
35 8 5 8 56
Senegal (Kaolack and Fatick)
40 6 4 9 59
Guinea (Dubréka and Coyah)
40 3 4 7 54
Guinea Bissau (Bafata)
20 3 3 5 31
Total 135 20 16 29 200
0%10%20%30%40%50%60%70%80%90%
100%
GBA(MOS)
CRD (LIS) MOS LIS Dubreka Coyah Bafata
The Gambia Senegal (BassinArachidier)
Guinea GuineaBissau
Overall
farmer herder milk vendors
29
5.2 Farmers’ perceptions of animal diseases 5.2.1 Disease importance ranking
5.2.1.1 Results presented by country
In order to obtain information on the importance of diseases/symptoms as perceived
by the PRA participants a ranking was applied during the group discussions. Results
for ranks are based on scoring for the 5 highest ranked diseases/symptoms in all
countries and expressed as weighted average.
Results for cattle are shown in Table 2. Potential zoonoses or clinical symptoms,
which could indicate zoonotic infections, are shaded in grey. In addition results
including the top-ten list of diseases/symptoms are presented graphically by country
in Annex 1b (Graphs 1-4).
The ranking for the five most important diseases/symptoms indicated always in all
countries “unspecific diarrhoea” and H.S. (pasteurellosis). With the exception of
Guinea, also Black quarter was ranked high, even number one in Guinea Bissau.
Symptoms/diseases with likely zoonotic implications were reported in all countries
with regional variations. Anthrax was considered as the second most important
disease in Guinea Bissau. Abortions and hygromas (local name “bakale”) were
ranked as number four and five respectively in Guinea and Guinea Bissau but not
mentioned by farmers in Senegal and The Gambia.
30
Table 2: Top-five diseases or symptoms in cattle as ranked by farmers´ in terms
of importance by country
Symptoms/ diseases
Gambia Guinea Guinea Bissau
Senegal
Total no. of farmers 35 40 20 40
Ranking WA* Ranking WA* Ranking WA* Ranking WA*
Abortion - - 4 1.3 4 1.4 - -
Anthrax - - 5 1.1 2 1.9 - -
BQ 4 1.1 - - 1 2.7 4 1.3
Diarrhoea (unspecific) 1 2.8 1 1.9 3 1.6 5 0.9
FMD 5 1.0 - - - - - -
H.S. 3 1.4 5 1.1 4 1.4 1 2.6
Hygroma - - 5 1.1 5 1.3 - -
Foot problems (unspecific)
- - 3 1.5 - - - -
Lumpy skin - - 2 1.6 - - - -
Tick damage/fly sore - - - - - - 2 2.3
Trypanosomosis 2 1.8 - - - - 3 1.6
* Weighted average (WA) of scores
The results for disease ranking for the five most important diseases/symptoms for
small ruminants are presented in Table 3. Potentially zoonotic diseases or associated
symptoms are shaded grey. In addition, the results for the ten highest ranked
diseases/symptoms are presented graphically by country in the Annex 1b (Graph 5-
8).
PPR was considered in three countries as the “number-one” disease and in one
country number three. All other diseases/symptoms including likely zoonoses varied
widely between the countries. With the exception of Guinea Bissau abortions were
always within the top-five list. As stated already for cattle in Guinea Bissau anthrax
was highly ranked also in SR in this country.
31
Table 3: Top-five diseases or symptoms in SR as ranked by farmers´ in terms
of importance by country
Symptoms Gambia Guinea Guinea Bissau Senegal
Total no. of farmers 35 40 20 40
Ranking WA* Ranking WA* Ranking WA* Ranking WA*
Abortion 4 1.0 2 0.9 2 2.0
Anthrax 2 2.3
BQ 4 1.0
Diarrhoea (unspecific) 1 2.7 4 0.6
Foot problems (unspecific) 3 0.8 5 0.8
Mange 3 1.3
Nervous symptoms 5 0,4
Pasteurellosis 3 1.1 3 1.4
PPR 2 1.2 1 3.7 1 4.3 1 2.6
Tick damage/fly sore 4 1.3
Trypanosomosis 5 0.5 5 0.8
* Weighted average (WA) of scores
5.2.1.2 Results presented by production system
In The Gambia and in Senegal the PRA was carried out on farms characterised by
different production systems. Results for the five most important diseases/symptoms
in cattle according to the production system are shown in Table 4 for The Gambia
and Table 5 for Senegal.
In The Gambia differences in disease ranking between the production systems were
observed. Trypanosomosis was ranked highest in the MOPS, but only given 5th rank
in the LIPS. In addition, more importance was attributed to tick infestations in the
MOPS, wherever BQ, FMD and constipation were more frequent in the LIPS.
32
Table 4: Top-five diseases or symptoms in cattle as ranked by farmers´ in The
Gambia in terms of importance by production system
Symptoms/diseases GBA (MOPS) CRD (LIPS)
Total no. of farmers 15 20
Ranking WA* Ranking WA*
BQ - - 2 1.7
Constipation (unspecific) - - 3 1.1
Diarrhoea (unspecific) 2 2.9 1 2.8
FMD 5 0.7 3 1.1
H.S. - - 2 2.2
Lumpy skin 4 0.5 4 0.8
Tick damage/fly sore 3 1.9 - -
Trypanosomosis 1 3.3 5 0.7
* Weighted average (WA) of scores
Results for disease ranking according to production systems were more homogeneous
in Senegal (Bassin Arachidier) than in The Gambia. The five most important
diseases/symptoms were nearly equally ranked with the exception of diarrhoea, FMD
and poisoning (Table 5). Diarrhoea and poisoning were ranked more highly in the
MOPS, FMD higher in the LIPS.
Table 5: Top-five diseases or symptoms in cattle as ranked by farmers´ in
Senegal in terms of importance by production system
Symptoms MOPS LIPS
Total no. of farmers 20 20
Ranking WA* Ranking WA*
BQ 4 1.2 4 1.3
Diarrhoea 3 1.3 - -
FMD - 5 0.9
H.S. 2 2.0 1 3.3
Poisoning 5 1.0 - -
Tick damage/fly sore 1 2.4 2 2.3
33
Trypanosomosis 3 1.3 3 1.9
* Weighted average (WA) of scores
Summary: • Results from disease ranking from cattle differed between the countries. However,
H.S. and symptoms of diarrhoea were always among the top-five in all four
countries.
• Reports on infections with zoonotic character varied widely between the four
countries. Anthrax was number two in Guinea. Clinical hygromas (indicating
brucellosis) were only mentioned by farmers in Guinea Bissau and Guinea and
ranked as number 5.
• In small ruminants PPR was the highest ranked disease in three of the four
countries. In The Gambia, where unspecific diarrhoea and Pasteurellosis were
ranked higher, PPR was number three among the “top five”.
• Potential zoonotic infections such as anthrax were only among the top-five list in
Guinea Bissau.
• Differences in disease importance ranking according to the production system
were observed for The Gambia while in Senegal responses were more similar.
5.2.2 Chronic diseases
During group discussions information was collected on chronic diseases in cattle and
small ruminants. Results for cattle are shown in Table 6 and for small ruminants in
Table 7. Five farmers amongst the PRA groups were selected randomly in each
location to quantify responses (see 4.3). A chronic disease was defined as an illness,
which lasted more than four weeks.
5.2.2.1 Chronic diseases in cattle
During group discussions a total of 68 cases of long lasting diseases in cattle were
reported by respondents. In 21 cattle the cause of the disease was unknown. The 68
cases were observed on 60 different farms.
34
Among the chronic diseases reported in cattle, brucellosis (14/47) and
trypanosomosis (10/47) were most frequently reported. The latter disease was noted
by participants in all four countries, whereas brucellosis was only reported in Guinea
and Guinea Bissau. The differences observations of brucellosis between countries
were significant.
Table 6: Reports by farmers during group discussions of chronic (long lasting)
diseases in cattle
Disease suspected Overall Gambia Guinea Guinea Bissau Senegal
Total no of farmers 185 35 40 20 40
No. of farmers with cattle
suffering from chronic diseases
47 19 25 13 7
Brucellosis (Hygroma) 14 0 a 10 b 4 b 0 a
BQ 3 0 3 0 0
Diarrhoea (unspecific) 1 0 1 0 0
Endoparasites 3 0 2 1 0
H.S. 3 3 0 0 0
Poisoning (plastic bag) 2 0 2 0 0
Lumpy skin 4 1 0 3 0
Mange 3 0 0 3 0
Mastitis 1 0 0 1 0
Pasteurellosis 3 0 0 1 2
Trypanosomosis 10 4 3 0 3
Unknown (unspecific symptoms) 15 9 4 0 2
a:b (p<0.05)
When asking farmers on their consumption habit of meat and milk of chronically sick
cattle, the majority (34/60) reported that they always consume such meat and milk.
Among the observed chronic diseases in cattle brucellosis (n= 14) and mastitis (n= 1)
have relevant importance as milk-borne infection for man, yet milk was always
consumed from diseased animals.
35
Differences in milk consumption patterns related to the production system were
observed (Table 7). A significantly higher proportion of farmers in the LIPS
consumed meat from sick cattle. The difference in milk consumption practices was
significant (p= 0,06) although not at the p=0.05 level.
Table 7: Consumption patterns (on farm) for meat and milk from chronic sick
cattle related to production system
MOPS LIPS
No. of farmers who reported having chronically sick cattle 14 46
No. of farmers consuming raw/fermented milk from sick animals 3 * 25 *
No. of farmers consuming meat from sick animals 1 a 33 b
a:b (p<0.05) * (p= 0.06)
5.2.2.2 Chronic diseases in small ruminants
A total of 22 chronic cases of diseases in SR was reported by 22 farmers (Annex 1b,
Table 1). Only in nine of these cases were the symptoms described sufficientsly by
respondents to identify the disease. Mange was reported most frequently (3/9),
followed by one case each of arthritis, BQ, heartwater, lumpy skin, metritis and orf.
Differences in the consumption practices according to production system were also
observed for small ruminants. None of the farmers reporting chronically sick animals
in the MOPS (n= 4) consumed meat from such animals whereas 13 of 18 did it in the
LIPS. Milk from small ruminants is usually not consumed at all.
Summary:
• With regional variations, brucellosis and trypanosomosis were the most
frequently observed chronic diseases in cattle. Cases of brucellosis were only
observed by farmers in Guinea and Guinea Bissau.
• Specific chronic diseases in SR (n= 9) were less frequently reported than in cattle
(35). Mange (n= 3) was recorded most often.
• The practice of consuming milk and/or meat from chronically ill animals clearly
differed between the production systems. The majority of farmers in the LIPS
36
system still consume meat and/or milk from chronic sick cattle or SR, while this
was done only exceptionally by farmers from the MOPS.
5.3 Farmers perception on zoonoses
5.3.1 Questionnaire results for zoonoses
5.3.1.1 Results by country
In the semi-structured questionnaires farmers were asked to name at least three
animal diseases, which might cause also infection in man. Results are presented in
Table 8.
Compared to Senegal a significantly higher proportion of farmers in The Gambia,
Guinea and Guinea Bissau had knowledge of at least one zoonotic infection. With the
exception of Guinea Bissau the knowledge of second or third zoonoses was weak in
all other countries. The difference was significant.
Table 8: Proportion of farmers by country with knowledge of unspecified
zoonotic diseases
Overall Gambia Guinea Guinea Bissau Senegal
No. of farmers interviewed 135 35 40 20 40
Farmers knowing of one disease
likely to be zoonotic (%) 53 51a 58 a 65 a 20 b
Farmers knowing of two diseases
likely to be zoonotic (%) 18 6 a 10 a 65 b 13 a
Farmers knowing of three diseases
likely to be zoonotic (%) 12 0 a 5 a 55 b 8 a
a:b (p<0.05)
Thereafter, farmers were asked to list these zoonotic infections. Table 9 gives a list
by country of the first disease mentioned by farmers as likely to be zoonotic.
37
Brucellosis was reported most frequently, followed by anthrax, rabies and bovine
tuberculosis. All these infections were reported by farmers in each of the four
countries, however with regional variations. Brucellosis was again more frequently
reported in Guinea and Guinea Bissau (p= 0.06) than in Senegal and The Gambia.
Less frequently reported in some of the countries were Cl. butolinum and FMD. One
farmer in Senegal believed that HIV and BQ were zoonotic infections.
Table 9: Numbers of farmers identifying diseases with perceived zoonotic
character (first mentioned disease)
Overall Gambia Guinea Guinea Bissau
Senegal
Total no of farmers 135 35 40 20 40
Brucellosis 26 3 a 15 b 7 b 1 a
Anthrax 20 7 4 6 7
Rabies 19 7 4 6 2
BTB 7 2 1 1 3
Cl. botulinum 2 - - - 2
FMD 1 - - - 1
HIV 1 - - - 1
BQ 1 - - - 1
a:b (p<0.05)
In the next step farmers were asked to rank four given selected zoonoses (rabies,
anthrax, BTB and brucellosis) according to their importance. The aggregate ranks
were calculated based on scorings as follows: the first zoonotic disease mentioned
was assigned a score of 4, the second 3 etc. Then the total scores were calculated.
Results are presented in Table 10 by country.
Among these four zoonoses, rabies was ranked highest in three of the four countries.
In Guinea anthrax was graded as the most important zoonotic disease. In three of the
four countries, brucellosis was believed to be the second most important zoonosis.
Less importance was accorded to BTB.
38
Table 10: Farmers´ ranking of the importance of four given zoonoses by country
Gambia Guinea Guinea Bissau Senegal
Total no of farmers 35 40 20 40
Rabies 1 3 1 1
Anthrax 2 1 3 4
BTB 4 4 4 3
Brucellosis 3 2 2 2
Information was also collected on farmers’ specific knowledge for each of these four
zoonoses. Results are presented in Table 11a – d. The following topics were
discussed:
• Knowledge of the disease and key symptoms in cattle
• Modes of transmission
• Preventive measures
• Cases in animals observed by farmers (during the last three years).
For rabies (Table 11a) regional differences in farmers’ level of knowledge were
observed, this being significantly higher in Guinea Bissau followed by Senegal.
Measures to prevent transmission (i.e. vaccination) were known by 100% of farmers
in Guinea Bissau and 83% of farmers in Senegal, but only by a minority of
respondents in The Gambia and Guinea. Suspected cases of rabies, all of them
observed in dogs, were reported by farmers in all countries.
Table 11a: Specific knowledge of rabies and clinical observations in animals during the last three years by country (% of farmers)
Rabies Gambia Guinea Guinea
Bissau Senegal
Total no of farmers 35 40 20 40
39
Disease & symptoms in animals 69 a 65 a 100 b 93 b
Modes of transmission 54 a 38 a 100 b 90 b
Preventive measures 43 a 28 a 100 b 83 b
Observed in animals* 14 a 3 a 5 a 10 a
a:b (p<0.05) * dogs
Similar differences in farmers’ knowledge of anthrax were observed. Symptoms in
cattle were best known in Guinea Bissau. However, knowledge about transmission
and prevention was generally poor in all countries. Clinical cases of anthrax in cattle
and small ruminants were most frequently observed in Guinea Bissau.
Table 11b: Specific knowledge of anthrax and clinical observations in animals
during the last three years by country (% of farmers)
Anthrax Gambia Guinea Guinea Bissau
Senegal
Total no farmers 35 40 20 40
Disease & symptoms in animals 40 a 50 a 75 b 10 b
Modes of transmission 20 a 33 a 25 a 0 c
Preventive measures 17 a 28 a 25 a 0 b
Observed in animals* 9 a 5 a 25 b 0 a
a:b:c (p<0.05) *cattle or small ruminants
Symptoms, transmission and prevention of BTB were well known by farmers in
Guinea Bissau, whereas it was very poor in the other three countries. Suspected
clinical cases of BTB (described as a vasting disease and characterised by loss of
weight and chronic pulmonary symptoms) were only observed by farmers in Guinea
Bissau.
Table 11c: Specific knowledge of BTB and clinical observations in animals
during the last three years by country (% of farmers)
BTB Gambia Guinea Guinea Bissau
Senegal
Total no farmers 35 40 20 40
Disease & symptoms in animals 20 a 50 b 75 b 15 a
40
Modes of transmission 9 a 15 a 75 b 13 a
Preventive measures 6 a 3 a 75 b 10 a
Observed in animals* 0 0 10 0
a:b (p<0.05) *cattle
The differences in reports of bovine brucellosis between the countries were
significant. More farmers had specific knowledge of all aspects in Guinea Bissau.
Though the symptoms of the disease are better known by farmers in Guinea, the
knowledge of transmission and prevention was poor, likewise in The Gambia and
Senegal. Suspected brucellosis-like symptoms in cattle were most frequently
observed in Guinea Bissau, followed by Guinea (see also 5.9.1).
Table 11d: Specific knowledge of bovine brucellosis and clinical observations in
animals during the last three years by country (% of farmers)
Brucellosis Gambia Guinea Guinea Bissau
Senegal
Total no farmers 35 40 20 40
Disease & symptoms in animals 23 a 75 b 100 c 55 b
Modes of transmission 11 a 28 a 100 b 23 a
Preventive measures 6 a 3 a 65 b 18 a
Observed in animals* 3 a 30 b 80 c 8 a
a:b:c (p<0.05) * cattle
5.3.1.2 Results by production system
Farmers’ knowledge about these four zoonoses (rabies, anthrax, BTB and brucellosis)
was not significantly influenced by the production system. The results are presented
in Annex 1b (Tables 2a-d).
Summary:
• Farmers’ knowledge of zoonoses differed between countries but not by the
production system.
• Among the four given zoonoses (rabies, anthrax, BTB and brucellosis) rabies was
ranked highest by farmers in Guinea Bissau, The Gambia and Senegal while in
41
Guinea anthrax was ranked highest. Number two zoonosis was brucellosis
(Guinea, Guinea Bissau and Senegal) and anthrax respectively in The Gambia.
• The highest level of knowledge about these zoonoses was found in farmers from
Guinea Bissau. This includes the knowledge of symptoms and, with the exception
of anthrax, also the transmission route and how to prevent transmission.
• Clinical cases of anthrax and brucellosis in cattle were more frequently reported
by farmers in Guinea Bissau than in the other three countries. In addition,
brucellosis in cattle was more often observed by farmers in Guinea than in
Senegal and The Gambia, where infections were not common as evidenced by the
ITC prevalence study (see 5.9.1).
5.3.2 Group discussion results for zoonoses Farmers’ knowledge about zoonoses in The Gambia was very limited. There was a
general understanding that some animal diseases can be transmitted to people but the
respondents could not be more specific. Anthrax was mentioned as a zoonosis by four
respondents in two of the seven locations. However, the high risk of transmission to
man was unknown. It was actually reported that meat of suspected anthrax cases is
consumed after a specific local treatment (adding of thorns of a local plant called
“sumpo” when cooking). Another disease of zoonotic importance mentioned was
lumpy skin disease in cattle. One respondent pointed out that human TB can be
transmitted via sputum from man to cattle; another farmer suffered from serious
diarrhoea in the last year and related it to the consumption of meat from a chronically
sick and emaciated bovine.
In seven of the eight selected locations in Guinea farmers had some knowledge of
animal diseases, which can also affect man. Anthrax was always cited. Some
respondents believed the steam during cooking to be a likely source of infection for
man. Only in two locations were animals, suspected to have died from anthrax,
burned and buried. In particular if veterinary services are not available, e.g. when an
animal died “far away in the bush” during transhumance, only the spleen is discarded
but the meat is consumed after proper cooking. Recent outbreaks of anthrax in cattle
were reported from two locations. In addition 10-15 cases of anthrax in cattle were
observed in 2001 in a cattle herd from Tambaya when on transhumance in
42
Forehcariah. Furthermore rabies, brucellosis, BQ, lumpy skin and tuberculosis were
mentioned. However, the modes of transmission were often not known. Related to
brucellosis the majority of farmers pointed out that cattle with hygromas are not
considered to be sick. Therefore the milk of those cattle is consumed. However, there
was a consensus that they would never buy such an animal from markets or
neighbours. In three of the eight locations respondents mentioned BQ as a zoonotic
infection. Only in one location are such carcasses burned, otherwise the meat is
consumed, with the exception of the affected parts.
The majority of participants in the group discussions in Senegal believed that some
animal diseases can be transmitted to humans through milk and meat. However, they
were usually not able to specify any such disease. Only in two locations was anthrax
cited as a zoonosis. When observed, meat is not consumed and the carcass needs to
be burned and buried. Other diseases, thought to be zoonotic, which were mentioned
only in one location each, were mastitis, BTB, FMD and rabies. Respondents related
some experiences of similar disease symptoms observed in livestock and people, but
these were of anecdotal value only. With respect to the handling of an aborted foetus
(see below) there is a traditional belief in one location that hanging it on a tree might
reduce the occurrence of abortion in the herd.
As was the case with the replies to the questionnaire, the level of knowledge
emerging from the group discussions was found to be higher in Guinea Bissau than in
the other three countries. In all locations participants had specific knowledge of
rabies, brucellosis, BTB and anthrax. The transmission routes and preventive
measures were usually clearly known. Only in two locations no knowledge of the
measures for avoiding anthrax infection in man was established.
Summary:
• Farmers in Guinea Bissau appear to have a higher level of knowledge about
zoonotic diseases. This includes knowledge of the symptoms, transmission routes
and how to avoid transmission.
• In particular, knowledge of the public health importance of anthrax was
generally poor. The majority of participants in The Gambia, Senegal and Guinea
43
indicated that meat of such animals is consumed after proper cooking or
application of traditional treatment.
• The results of group discussions in Guinea indicated that cattle with hygroma are
often not considered to be sick and their milk is consumed unpasteurised.
5.4 Specific observations on brucellosis 5.4.1 Symptoms of brucellosis
Information on the pathognomic symptoms of brucellosis in cattle (hygroma) and
potentially linked symptoms like abortions (cattle and SR) and sterility (cattle) were
collected during interviews and in group discussions. For quantification of results
obtained from group discussions, five farmers with cattle and/or SR were selected
randomly during each group session (see 4.3).
Cow with hygroma in Guinea Bissau
5.4.1.1 Results by country for cattle
Results from questionnaires and group discussions are consistent regarding reports of
clinical hygromas and abortions in cattle (Table 12). The frequency of abortions was
higher in cattle on farms in Guinea Bissau and Guinea than in The Gambia and
Senegal. The differences are significant.
44
Table 12: Clinical signs potentially indicative of brucellosis infection observed
by farmers in their cattle (proportion of farmers by country)
Gambia Guinea Guinea Bissau Senegal
Questionnaire results
No. of farmers interviewed 35
40 20 40
% observing abortions in their
cattle (during last 12 months) 23 a
53 b 70 b 33 a
% observing hygromas in
their cattle 3 a
65 b 75 b 5 a
% observing infertile cows in
their cattle
(>2 years without calf) 6 a
45 a 60 b 25 a
Group discussion results
No. of respondents 1 35 40 20 40
% observing abortions in their
cattle (during last 12 months)
29 a 6% b 95 c 43 a
% observing hygromas in
their cattle
0 a 60 b 75 b 0 a
1 Five randomly selected farmers per group discussion a:b:c (p<0.05)
5.4.1.2 Results by country for small ruminants
Results from interviews and group discussions on abortions observed in SR both
indicate that there is no significant difference between countries (Table 13).
45
Table 13: Clinical signs potentially indicative of brucellosis infection observed
by farmers in their small ruminants (proportion of farmers by country)
Gambia Guinea Guinea Bissau Senegal
Questionnaire results
No. of farmers interviewed 35 40
20 40
% observing abortions in their
small ruminants
(during last 12 months) 34 20
15 35
Group discussion results No. of respondents 1 35 40 20 40
% observing abortions in their
small ruminants (during last 12
months) 57 53 35 65 1 Five randomly selected farmers per group discussion
5.4.1.3 Results by production system
The number of abortions reported during the last 12 months did not differ
significantly between the production systems within the same country as shown in
Table 14.
Table 14: Abortions observed by farmers in their cattle or small ruminants
(proportion of farmers by production system and country)
Questionnaire Results Gambia Senegal
MOPS LIPS MOPS LIPS
No. of farmers interviewed 15 20 20 20
46
% observing abortions in their
cattle (during last 12 months)
20 35 60 55
% observing abortions in their
small ruminants (during last
12 months)
40 70 75 60
1 Five randomly selected farmers per group discussion
5.4.2 Handling of aborted foetus
5.4.2.1 Results by country
Information was collected during the interviews on how aborted foetuses are handled.
Farmers’answers were categorised as follows:
• Definite destruction (foetus are buried or cremated)
• Partial destruction
o Thrown away
o Fed to dogs
o Hanging on a tree
• Seasonal (dry season) definite or partial (rainy season) destruction (same
subcategories as described above)
Results from the questionnaire indicate regional differences in handling of aborted
foetuses. A significantly higher proportion of farmers in Guinea Bissau (13/20) and
in Guinea (16/40), bury the aborted foetuses. This proportion is even higher in the
rainy season as some farmers practise this method only during this period. The
majority of farmers in The Gambia (29/35) and Senegal (28/40) simply throw away
the foetuses (Table 15).
Table 15: Ways of handling aborted foetuses by country (proportion of farmers
interviewed)
Questionnaire Results Gambia Guinea
Guinea Bissau Senegal
No. of farmers interviewed 35 40 20 40
% burying or cremating (definite destruction) 9 a 40 b 65 b 20 a
47
% throwing away (partial destruction) 82 a 20 b - b 70 a
% hanging on a tree (partial destruction) - - - 5 % feeding to dogs (partial destruction) 9 - - 5 % throwing away or burying according to season - a 38 b 25 a - a % didn’t know 0 2 15 -
a:b (p<0.05)
5.4.2.2 Results by production system
No differences in the handling of aborted foetuses on farm according to the
production system were found. Results are nearly similar as presented in Table 16.
Table 16: Ways of handling aborted foetuses by production system and country
(proportion of farmers interviewed)
Questionnaire Results Gambia Senegal
MOPS LIPS MOPS LIPS
No. of farmers interviewed 15 20 20 20
% burying or cremating (definite
destruction)
7 10 15 20
% hanging on a tree (partial
destruction)
-
- - 10
% feeding to dogs (partial
destruction) 13 7 5 5
% throwing away or burying
according to season 80 83 80 65
5.4.3 Handling of milk from cows with previous history of abortion or observed
hygromas
5.4.3.1 Results by country
Farmers were asked what they do with milk from cows with an history of abortion
(last 12 months) or with clinical hygromas. As shown in Table 17, the majority of
48
farmers still consume milk from such cattle. However, fewer farmers do it in Guinea
Bissau (11/20) and nine of twenty farmers indicated that this milk is fed to dogs, a
habit which was more common in Guinea Bissau than in the other three countries.
Table 17 : Farmers’ ways of dealing with milk from cows with a history of
abortion or observed hygroma by country (proportion of farmers)
Questionnaire Results Gambia Guinea
Guinea Bissau Senegal
No. of farmers interviewed 35 40 20 40
% throwing milk away 23 a 23 a 0 b 13 ab
% feeding milk to dogs 0 a 3 a 45 b 8 a
% consuming milk 77 73 55 80
a:b (p<0.05)
5.4.3.2 Results by production system
The handling of milk from cows with a history of abortion or observed hygromas did
not differ significantly between the production systems (Table 18).
Table 18: Farmers’ ways of dealing with milk from cows with a history of
abortion or observed hygroma by production system and country
(proportion of farmers)
Questionnaire Results Gambia Senegal
MOPS LIPS MOPS LIPS
No. of farmers interviewed 15 20 20 20
% throwing milk away 26 10 10 15
% feeding milk to dogs - - - 15
% consuming milk 74 90 90 70
Summary:
49
• The number of reports of abortions and hygromas in cattle was significantly
higher in Guinea and Guinea Bissau. Reports of sterile cows were more frequent
in Guinea Bissau.
• The occurrence of abortions and hygromas in cattle was similarly distributed in
both production system
• Abortions in SR were not influenced by country or production systems
• Handling of aborted foetuses differed between countries but not between
production systems
• Handling of milk produced from cows with abortion history or observed hygroma
differed also between countries but not between production systems
5.5 Attitudes to the importance of quality of livestock products During group discussions farmers’ perceptions of the importance of meat and milk-
quality produced on-farm was discussed. This included the following key issues:
• diseases which can influence the quality of milk and meat,
• changes related to animal diseases observed in meat and milk,
• handling of affected milk and meat.
Information from the questionnaire on handling of milk produced on-farm was also
included (5.4.3).
5.5.1 Observations on meat quality related to animal diseases
In all group discussions participants agreed that livestock diseases can affect the
quality of meat. The main indicators for reduced meat quality mentioned were bad
smell, pale colour, and higher water content. The handling of such meat and specific
knowledge of the causes varied widely between the countries.
Participants in The Gambia noted the following changes in meat quality from sick
animals: slimy, higher water content, black spots on meat and intestines, pale colour
and hardening of the liver. The causes were usually not known. In two locations
participants were able to relate changes in meat, such as black colour of meat and
blood to anthrax infection. As mentioned above, some participants had some
50
knowledge about the zoonotic character of this disease. Meat from animals thought to
be diseased or meat of bad quality is usually consumed after proper cooking or
sometimes washed with vinegar before cooking. No differences in perceptions related
to meat quality were observed in the different production systems.
The main changes in meat of bad quality reported by respondents in Senegal were:
black spots on the meat, pale, containing less blood/anaemic, higher water content,
tasteless, bad smell and spots on the liver. The causes were usually not known. Some
participants in one location related bad smell and taste of meat, slimy and pale colour
to emaciation and pulmo-nasal symptoms in cattle, yet they consumed this meat.
There was a general consensus that such affected meat can still be consumed after
proper cooking. Differences in perception related to the production systems were not
observed.
The observations of participants in Guinea regarding meat quality were in general
similar to the observations made in Senegal and The Gambia. In addition,
respondents were able to relate some changes to animal diseases. Farmers’
knowledge was better than in Senegal and The Gambia. In six of the eight locations,
participants were able to describe clearly the changes in meat due to anthrax:
enlarged spleen, black colour of meat and blood and rapid rotting. However, there
was little awareness of the related high risk to humans. As mentioned earlier (see
5.3.2) meat is often consumed in particular when animals died “far way in the bush”.
Other diseases causing changes in meat quality were BQ and lumpy skin.
Oedematous swelling of muscles was related to BQ. The affected part is discarded
but the remaining carcass usually consumed after proper cooking. Bad odour and
blood spots in meat, was linked to lumpy skin disease in cattle by some participants.
Participants in Guinea Bissau considered anthrax, BQ, pasteurellosis and
trypanosomosis as animal diseases, which reduce the quality of meat. Furthermore,
chronic diseases, which were not further specified, might lead to watery and anaemic
meat. The general changes in meat of bad quality were the same as listed for The
Gambia and Senegal. The changes in anthrax-infected animals were well known.
Only in one of the four locations did respondents state that such meat should be
51
consumed only after proper cooking and discarding of the spleen. Oedema in meat
was related to BQ; in this case the affected parts are discarded and the remaining
carcass is consumed.
Summary:
• The main indicators for reduced meat quality mentioned by farmers in all four
countries were bad smell, pale colour, and higher water content.
• The handling of such meat and specific knowledge of the causative agent varies
widely between the countries. The highest level of knowledge was found in
Guinea Bissau followed by Guinea. Comparatively, knowledge in The Gambia
and Senegal was poor. Accordingly meat of bad quality was also handled
differently, i.e. usually consumed in Senegal and The Gambia while often
discarded by farmers in Guinea Bissau.
5.5.2 Observations on milk related to animal diseases
There was a general agreement in all group discussions that milk is an excellent
source of energy and healthy but that certain animal diseases can affect the quality of
the product and may even be transmissible to man. Changes in milk quality were
generally characterized by a higher water content, clotting and faster fermentation.
Some respondents (Senegal and The Gambia) mentioned also slower fermentation as
a sign of reduced quality. This observation was mainly made by milk vendors.
The main indicators for milk of bad quality noted during group discussions in The
Gambia were as described above, plus discolouring, bad smell and presence of blood
spots. Participants agreed that such milk is not sold or consumed because it can pose
a health risk for the consumer. However, the nature of this risk could not be specified
by any of the respondents (milk vendors). Despite the general agreement that milk
can transmit diseases to man, it is usually not pasteurised. There is a traditional belief
of farmers that boiling of milk might reduce the milk yield of the lactating cow. Only
52
two farmers in one location (Sareh-Ngai, LIPS) pointed out that women after delivery
should only drink pasteurised milk to avoid the risk of transmission of disease.
During group discussions in Senegal milk of bad quality was characterized as
described above. Such milk is not sold and discarded by the farmers or vendors. In
Kaolack (a location representing the market-orientated system), some farmers related
reduced milk quality and changes in consistency to mastitis in F1 cattle. In the same
location milk vendors have heard about the advantages of boiling but they do not do
this because of the difficulty of selling such a milk product. However, some farmers
pasteurise their milk for home consumption. In two more locations, one representing
the MOPS (Fatick) and one the LIPS (Koutal), milk vendors and farmers boil their
milk when used for home consumption in particular when used for pregnant women
and young children. Milk is usually not heated due to the local belief that boiling of
milk over fire may result in sores on the udder of the cow which produced the milk.
Participants in Guinea described the same changes as mentioned above for reduced
milk quality. This milk is generally discarded. Respondents were usually not able to
relate changes in milk quality to animal diseases. Only in Tambaya one respondent
related lumpy skin disease to reduced quality of milk. The zoonotic importance of
brucellosis was only mentioned by farmers in Tanene and Tambaya. Farmers do not
boil milk in any of these locations.
The highest level of knowledge was again found in Guinea Bissau. Milk of poor
quality was characterized in group discussions by higher water content, faster
fermentation and clotting. If this is observed such milk will be discarded. The
diseases mentioned as influencing the quality of milk were brucellosis (mentioned in
3 locations) and TB (mentioned in one location). In three of the four chosen locations
(Sintuna Mamodou, Aguira and Buntusso) farmers boil milk for home consumption
so as to avoid the transmission of animal diseases. Fermented milk is never boiled.
Summary
• During all group discussions it was agreed, that milk is a good source of energy
and healthy but certain animal diseases can affect the quality of the product and
may even be transmissible to man.
53
• Poor quality milk was generally characterized by higher water content, clotting
and faster fermentation.
• Milk of reduced quality is usually not used for home consumption.
• Specific knowledge of the causative agents and of how to prevent transmission
varied between regions and was found to be best in Guinea Bissau.
• Milk in the region is usually consumed without heat treatment. However, most of
the respondents in Guinea Bissau heated their milk when used unfermented for
home consumption.
5.5.3 Handling of milk produced on farms
During the interviews, information was collected on the handling of milk produced
on farm. Results are given in Table 19.
All farmers filtered their milk before home consumption or sale. How the milk was
handled depended on the final product desired. In the case of sour milk production,
none of the farmers in the regions heated the milk. However, when consumed as raw
(unfermented) milk at home, regional differences were observed regarding boiling of
milk. Milk was boiled by the majority of farmers in Guinea Bissau (15/20).
Conversely in Senegal (9/40) and The Gambia (4/35) heat treatment was rarely
undertaken and in Guinea not at all.
Table 19: Processing of milk produced on-farm presented by country (% of
farmers)
Gambia Guinea Guinea Bissau Senegal
No. of farmers interviewed 35 40 20 40 % filtering 100 100 100 100
54
Raw milk % not heating 88 a 100 a 15 b 78 a % heating if used at home 9 a 0 a 85 b 22 a % heating
(only for pregnant woman) 3 - - -
Sour milk % not pasteurising 100 100 100 100 a:b (p<0.05)
Farms in the MOPS showed a higher acceptance of pasteurisation (Table 20).
However, the differences were not significant.
Table 20: Processing of milk produced on-farm presented by production system
and country (% of farmers)
Gambia Senegal
MOPS LIPS MOPS LIPS No of farmers interviewed 15 20 20 20 % filtering 100 100 100 100 Raw milk % not heating 87 90 65 90 % heating if used at home
13 5 35 10 Pasteurised
(only for pregnant woman) in % - 5 - - Sour milk Not pasteurised in % 100 100 100 100 Summary
• Milk produced on-farm was always filtered.
• Only raw milk was pasteurised.
• Acceptance of pasteurisation differed between the countries and was more
common on farms in Guinea Bissau.
55
• Use of pasteurisation was not significantly influenced by different production
systems.
5.6 Observations on zoonoses by other groups involved 5.6.1 Butchers
An overview of selected aspects of the slaughter process, such as number of animals
slaughtered per week, place of slaughter, time of slaughter etc. is given in Table 21.
The average number of animals slaughtered per week, location and butcher varied
between the countries. Generally fewer cattle (range 4.7 – 11.4) were slaughtered
than SR (6.8 – 24). With the exception of some butchers in Guinea (n= 2)
slaughtering was carried out at the local abattoirs and mainly between 6.00 and 10.00
in the morning. Meat was sold by the majority of butchers on the same day. Some
(7/28) sold their meat also on the following day. With few exceptions no records on
disease observations were kept by butchers. However, all butchers indicated that the
local veterinarian will be informed in case of any suspicion of epidemic diseases.
Table 21: General information on aspects related to slaughter and sale of cattle
and small ruminants (number per butcher per week)
Gambia Guinea Guinea Bissau Senegal
Slaughter animals per butcher/week
56
Cattle (mean) 11.4 (4.9,17.9) 4,7 (2.7, 6.7) 7.0 (6.3, 7.7) 4,9 (3.2, 6.6)
SR (mean) 24.0 (8.5, 39.5) 7,3 (1.2, 13.4) 17.5 (7.9, 27.1) 6,8 (2.7, 10.9)
No of butchers interviewed
8 7 6 9
Place of slaughter
Farm - 2 - -
abattoir 8 5 5 9
Time of slaughter
6-10 AM 6 5 5 8
other 2 2 - 1
Time of sale
Same day 7 6 4 5
Same & next day 1 1 1 4
Records on observations during slaughter do exist
yes 2 1 - -
Contacts to VH do exist
yes 8 7 5 9
In brackets CI for the mean
5.6.1.1 Butchers’ knowledge of zoonoses
Butchers were asked to list at least three zoonotic animal diseases. The knowledge of
butchers was found broadly similar in all locations and differences were not
significant (Table 22). The majority of butchers did know of at least one zoonotic
infection. Their knowledge of a second and third zoonosis was clearly limited. It
appears that butchers in The Gambia were better informed.
Table 22: Proportion of butchers with knowledge of unspecified zoonotic
diseases by country
Gambia Guinea Guinea Bissau
Senegal
No. of butchers interviewed 8 7 5 9 Butchers knowing of one disease 87 85 80 55
57
likely to be zoonotic (%) Butchers knowing of two diseases likely to be zoonotic (%) 50 28 40 22 Butchers knowing of three diseases likely to be zoonotic (%) 25 14 - 11
5.6.1.2 Zoonotic diseases observed during the last 12 months
The observations of zoonotic infections made by butchers during slaughter are shown
in Table 23. As most of the butchers did not record their observations it was usually
not possible to exactly quantify the number of cases observed. Therefore, the
numbers in Table 23 should be interpreted as recall data rather than as indicating the
exact number of cases.
The most frequently observed zoonosis was brucellosis, followed by anthrax and
cysticercosis. A higher frequency of anthrax and brucellosis were found in Guinea
Bissau and Guinea and of C. bovis infections in The Gambia.
Table 23: List of suspected diseases with zoonotic importance observed by
individual butchers during slaughter (last 12 months)
Symptoms Suspected disease
Gambia Guinea Guinea Bissau
Senegal
No. of butchers interviewed
8 7 5 9
Enlarged spleen Anthrax 1/8 3/7 3/5 -
Hygroma Brucellosis 1/8 4/7 3/5 -
Oedema (muscle) BQ 1/8 - - 1/9
Aphthae FMD - - - 1/9
Cysts C. bovis 4/8 - - 1/9
TB like lesions TB (M. bovis)* 1/9 - 1/5 1/9
* not confirmed
5.6.1.3 Knowledge of animal diseases which can influence meat quality
Butchers were asked to list diseases or to describe clinical symptoms, which can
influence the quality of meat (Table 24). The only symptom, which was known by
the majority of butchers, was liver indurations due to fasciolosis. Eight out of thirty
58
butchers indicated that symptoms related to anthrax and BTB can reduce meat
quality. Other diseases mentioned were trypanosomosis, cysticercosis and BQ.
Table 24: Butchers’ knowledge of symptoms and associated diseases which can
influence meat quality
Symptom observed
Related disease
Gambia (No.)
Guinea (No.)
GB (No.)
Senegal (No.)
No. butchers 8 7 5 9
Dark blood,
enlarged spleen
Anthrax 3/8 2/7 3/5 1/9
Liver
indurations
Fasciolosis 4/8 4/7 3/5 5/9
Pneumonia Pasteurellosis - 2/7 - -
Emaciation/
caseatic lesions
BTB 2/8 2/7 3/5 1/9
Watery/
pale meat
Trypanosomosis 3/8 - - 3/9
Cyst Cysticercosis 4/8 - 1/5 1/9
Oedema BQ - - - 4/9
5.6.1.4 Health status of butchers
Information was collected on the health status of butchers, including their regular
health check ups. Special emphasis was given on the occurrence of symptoms likely
related to TB infections and/or brucellosis, such as: arthritis and orchitis for possible
brucellosis infections and chronic coughing for TB.
Regular health checks and examination of faecal samples was noted when carried out
at least once during the last year. As shown in Table 25 the execution of regular
health checks of butchers varied between the countries. All butchers in The Gambia
confirmed having had such an investigation during the last year, a minority in
Senegal and Guinea and none of the butchers in Guinea Bissau. However, we could
not verify these health checks by a medical statement. No significantly differences
between countries were observed for brucellosis-like symptoms. Chronic cough, a
59
clinical symptom that could be related to TB in man, had a similar distribution in the
countries.
Table 25: Observations on health status of butchers
Total (No.)
Gambia (No.)
Guinea(No.)
GB (No.) Senegal (No.)
Total no. of butchers 28 8 5 7 9
Regular medical check-up 13 8 2 0 4
Self observation of selected symptoms possible related to brucellosis or TB:
Arthritis 18 5 5 4 3
Orchitis 5 1 0 3 1
Cough (chronic) 12 5 2 2 4
Summary • The majority of butchers knew of at least one zoonotic infection. Their knowledge
of a second and third zoonosis was clearly reduced.
• The zoonosis most frequently observed by butchers was brucellosis, followed by
anthrax. A higher frequency of these infections was reported for Guinea Bissau
and Guinea.
• 8 of 30 butchers indicated that symptoms related to anthrax and BTB can reduce
meat quality
• The extent to which butchers had regular health checks varied between
countries, None of these check-ups were documented by health certificates.
5.6.2 Veterinary health authorities
The veterinary authorities consulted were veterinarians and veterinary technicians as
shown in Table 26. The District Veterinary Officer (DVO) was always among the
respondents in each location.
Table 26: Information on the interviewed VH respondents
60
Gambia Guinea GB Senegal Total
Total respondents 8 3 3 6 20
Veterinarian 5 2 1 2 10
Veterinary technician 3 1 2 4 10 5.6.2.1 Observations on zoonotic infections in animals
This information was obtained from records of DVO´s for the last three years. The
most serious zoonosis was rabies followed by anthrax (Table 27). The number of
reported cases of rabies in animals (all of them dogs) was broadly similar in the four
countries. Conversely anthrax seems to occur more frequently in Guinea and Guinea
Bissau. The same applies for brucellosis in cattle. Infections due to C. bovis in cattle
were reported for Senegal and The Gambia. Rift Valley Fever (RVF) was only
observed in The Gambia were people also died. However, there was no proof of a
direct relationship between observed cases in animals and man in this outbreak.
Table 27: Zoonotic infection in animals and humans reported by VH respondents
in the study districts during the last 3 years
Symptoms How diagnosed
Gambia (No.)
Guinea (No.)
GB. (No.) Senegal (No.)
animals humans animals humans animals humans animals humans
Anthrax p.m. 2 - 6 1 4 - 2 -
Brucellosis Clinical &
p.m. - - 9 - 6 - 1 -
C. bovis p.m. 3 - - - - - 2 - Rabies RL* 3 2 5 - 2 2 5 - RVF RL* 3 3 - - - - - - * Reference laboratory p. m. post mortem 5.6.2.2 Animal diseases observed during the last year
Veterinary services were asked to list the most common animal diseases observed in
the last year and to rank them according to their importance. Results are presented in
Table 28 for cattle and Table 29 for SR. Zoonotic diseases are shaded grey. For
comparison the results from group discussions (see 5.2.1.1) are also included in the
Table.
61
Trypanosomosis was ranked highest in The Gambia, anthrax in Guinea and Guinea
Bissau and H.S. in Senegal. Brucellosis and anthrax were indicated as important
diseases only in Guinea and Guinea Bissau. With some exceptions there was a good
agreement between results obtained from veterinarians and farmers.
Table 28: Diseases or symptoms in cattle ranked by DVOs according to their
importance over the last 12 months by country
Gambia Guinea Guinea Bissau Senegal
Ranking (*)
Ranking (*)
Ranking (*)
Ranking (*)
Abortions - 5 (4) - -
Anthrax - 1 (5) 1 (2) -
BQ 4 (4) 4 (9) 3 (1) 3 (4)
Brucellosis - 3 (5) 4 (7) -
Endoparasites 3 (-) - - -
FMD 5 (5) - - -
H. S. 2 (3) 2 (5) 2 (5) 1 (1)
Lumpy skin - 5 (2) - 5 (-)
Pasteurellosis
Red water - - - 4 (-)
Trypanosomosis 1 (2) 4 (-) - 2 (3)
(*) Results of disease ranking by farmer (see 5.2.1.1)
In SR the highest ranked disease was PPR, followed by abortions (The Gambia) and
pasteurellosis (Guinea and Guinea Bissau). With one exception (Pasteurellosis in
Guinea was ranked lower by farmers than veterinarians) the results were broadly
similar to the rankings made by the farmers during the group discussions.
Table 29: Diseases or symptoms in SR ranked by DVOs according to their
importance over the last 12 months by country
Symptoms Gambia Guinea Guinea Bissau Senegal
62
Ranking (*)
Ranking (*)
Ranking (*)
Ranking (*)
Abortions 2 (4) - - -
Orf - 5 - -
Diarrhoea (unspecific) 4 (1) 4 (4) - 3 (6)
Pasteurellosis 3 (3) 2 (8) 2 (3)
Cowdryosis 3 (5) 5 (8)
PPR 1 (2) 1 (1) 1 (1) 1 (1)
Ticks 5 (7) - - -
Trypanosomosis - 2 - 4
(*) Results of disease ranking by farmer (see 5.2.1.1) Summary • The most important zoonosis in terms of mortality in man was rabies followed by
anthrax. The number of reported rabies cases in animals (all of them dogs) was
much the same in the four countries. However, more cases of anthrax and
brucellosis were observed in Guinea and Guinea Bissau than in the other
countries.
• The ranking of diseases by veterinarians was broadly similar to that done by the
farmers (see 5.2.1.1).
5.6.3 Public health sector
Hospitals and local health centres were visited in each country and a questionnaire
was administered (Table 30). Whenever possible the central hospital for the region
was contacted. In addition, local health centres were visited. The respondents
consisted of physicians, PH-officers and laboratory technicians.
Table 30: Numbers of interviewed public health facilities in the study districts
by country
Gambia GB Guinea Senegal
Location Hospital 3 1 1 2
Health centre 2 2 3 2
63
Respondent’s jobs
Physician 2 2 1 2
PH officer 2 1 3 2
Laboratory technician 1 - - -
When asked about exchange of information with veterinary health authorities,
differences between countries were observed as shown in Table 31. All respondents
in Guinea Bissau (3/3) and the majority in Guinea (3/4) indicated that there is a
regular exchange of data related to zoonoses.
Health Centres in Guinea Bissau (left) and Guinea (right)
Table 31: Exchange of information between PH and VH authorities
Gambia Guinea Guinea Bissau Senegal
Number of respondents 5 4 3 4
Number exchanging information
with VH authorities on a regular
basis 2 3 3 1
64
5.6.3.1 Observations of zoonotic infections during the last three years
Information about zoonotic infections reported during the last three years was
collected from PH authorities. The results are based only on reports made by the
personnel interviewed in hospitals or health centres and might be not representative
for the country.
Cases of rabies in humans were observed in all countries and in each location (Table
32), Rift Valley Fever (RVF) only in the CRD of the Gambia. Salmonellosis
infections in man were reported in all hospitals where the capacity for
microbiological investigations existed.
Table 32: Reports of zoonoses in humans over the last three years in the health
centres and hospitals visited
How diagnosed Gambia Guinea Guinea
Bissau Senegal
GBA CRD Coyah Dubréka Bafata Bassin Arachidier
Rabies RL yes yes yes yes yes yes Rift Valley Fever (RVF) RL - yes - - - -
Salmonellosis Bacteriology yes yes yes ? N.A. yes * Reference Laboratory N.A: Data not available 5.6.3.2 Diagnostic capacity of local health centres and hospitals with respect to
brucellosis-like infections and tuberculosis
Human brucellosis is characterised by a febrile reaction and usually associated with
osteoarticular manifestations (BATHKE, 1987, SEWELL and BROCKLESBY
1990). Diagnostic difficulties exist due to the similarity of these key symptoms (fever
and back/joint pain) with other widespread diseases such as malaria or flu-like
infections. Table 33 is an attempt to obtain information on the diagnosis and
65
prevalence of “flu-like infections” as well as TB in man covering the period of 12
months..
If laboratory facilities exist a malaria test is usually carried out in patients with such
“flu-like” infections. Otherwise malaria treatment is administered symptomatically.
The interviews in health centres and hospitals revealed that 1-5% (Senegal and The
Gambia) and 1-10% (Guinea and Guinea Bissau) of patients who test negative for
malaria still receive anti-malaria drugs without any differential diagnosis. Thus such
patients, could well be infected with brucellosis or other diseases with similar
symptoms.
The prevalence of TB-infections in man was found in the majority of locations in The
Gambia, Senegal and Guinea to be less than one percent. However, in Guinea Bissau
prevalences were higher and ranged between 6 and 10%. In most of the hospitals or
health centres visited no strain identification or transfer of samples to the National
Reference Laboratories was done. Hence the possible role and importance of M.
bovis in the epidemiology of human TB in these countries could not be assessed.
Samples are only occasionally sent for further identification to the National
Reference Laboratories from few of the locations in Guinea and The Gambia.
Table 33: Selected information on diagnostic procedures and prevalences related
to flu-like infections and TB among patients that visited the health
centres of this survey during the last year by country
Gambia GB Guinea Senegal
Location GBA CRD Bafata Coyah Dubréka Bassin Arachidier
Number of health
centres / hospitals 2 3 3 2 2 4
66
visited
Standard procedure for patients with “flu-like symptoms” (i.e. malaria, flu, brucellosis)
Malaria test done if
available 2 2 2 2 0 2
If test unavailable
malaria treatment
given without test 0 1 1 0 0 2
Proportions of malaria test negative patients reported (No. of PH facilities)
1-5% 2 2 1 1 0 4
6-10% 0 0 2 1 0 0
Test not applied 0 1 0 0 2 0
Proportions of TB patients reported in the last year (No. of PH facilities)
<1% 2 3 0 2 1 3
1-5% 0 0 0 1 0 1
6-10% 0 0 3 0 0 0
Strain identification for M. bovis undertaken (No. of PH facilities)
Not performed at all 1 2 3 1 0 4
Applied but not
regularly 1 1 0 2 1 0
5.6.3.3 Specific knowledge of brucellosis
The specific knowledge of personnel interviewed in the hospitals or health centres
was found to be very limited (Table 34). Only in five of the 16 locations visited were
the disease and symptoms in man known. The diagnostic capacity to apply
brucellosis specific tests did not exist in any of the locations. Moreover, only one
physician from Senegal had knowledge of the diagnostic procedures.
Table 34: Knowledge of brucellosis symptoms in man and diagnostic procedures
(number of hospitals or health centres by country)
Gambia GB Guinea Senegal
Location GBA CRD Bafata Coyah Dubréka Bassin
Arachidier
67
Health centre/hospitals
visited
2 3 3 2 2 4
Number with knowledge of:
Brucellosis infection and
symptoms in man 1 0 1 1 0 2
Diagnostic procedures 0 0 0 0 0 1
Number where test is applied if the disease is suspected 0 0 0 0 0 0
Summary • Rabies was the zoonosis ranked highest by public health authorities followed by
Salmonella infections.
• Patients with “brucellosis or flu -like” infections (fever and back/joint pain) are
tested for malaria where laboratory facilities are available. If not, malaria
treatment is administered symptomatically without differential diagnosis, e.g. for
brucellosis.
• The personnel’s knowledge of brucellosis (symptoms, transmission etc.) was very
limited, laboratory tests were not undertaken in any of the visited locations.
• Strain identification for M. bovis in patients with symptoms of TB was not carried
out in any of the health centres/hospitals visited in Guinea Bissau and Senegal
and rarely performed in The Gambia and Guinea.
5.7 Potential direct and indirect losses due to brucellosis 5.7.1 General herd parameters
The herd structure is presented in Table 35. Herd sizes differed significantly between
the regions with larger average herd sizes in Guinea Bissau (159) and Guinea (136)
than in Senegal (81) and The Gambia (61).
Table 35: Mean herd sizes and proportion of bulls, cows, heifers and calves
based on questionnaires by country
Herd size/ Gambia Guinea Guinea Senegal
68
composition Bissau Overall mean size (100%)
61a
(46.6,74,6) 136 b
(108.7,162.9) 159 b
(92.1,218.7) 81a
(62.8,98.6)% Bulls (not castrated >3 yrs) 2,3% 6,7% 2,2% 3,6% % Cows (after calving) 43,6% 44,3% 53,3% 54,7% % Heifers (>1 year until calving) 23,1% 22,0% 25,3% 19,0% % Calves (0 – 1yr.) 24,1% 19,6% 18,9% 13,6%
a:b (<0.05) In brackets: CI
The predominant cattle breed in Guinea, The Gambia and Guinea Bissau is the
trypanotolerant N´Dama and in Senegal the Zebu type of cattle. F1 cattle (crosses
with exotic breeds) were only present in Senegal and The Gambia on farms
representing the MOPS (Table 36).
Table 36: Cattle breeds in the study population (number of farms)
Gambia Guinea Guinea
Bissau Senegal*
Breed/Location GBA
(MOPS)
CRD
(LIPS)
Coyah Dubréka Bafata MOPS LIPS
No of farms 15 20 20 20 20 20 20
N´Dama - 20 20 20 20 - 1
N´Dama & F1 14 - - - - - -
N´Dama & WAS* - - - - - - 2
F1 1 - - - - 1 -
69
Zebu - - - - - - 11
Zebu & F1 - - - - - 14 -
Zebu & N´Dama - - - - - - 5
Zebu & N´Dama &
F1
- - - - - 5 -
Zebu & WAS* - - - - - 4
* West African shorthorn
5.7.2 Direct and indirect losses due to brucellosis (abortions and cow sterility)
To get some information on the direct and indirect losses potentially attributable to
brucellosis, observations on infertile cows and cases of abortions in cattle and SR on
herd level were recorded. A cow was considered to be sterile if it had not produced a
calf during the last three years. Observations on sterile cows and cases of abortions
were more frequent in herds from Guinea Bissau and Guinea (Table 37). In SR no
significant differences between the countries were detected.
Table 37: Selected herd fertility parameters
Gambia Guinea Guinea
Bissau
Senegal
Location CRD Dubréka Bafata LIPS
No of farmers interviewed 35 40 20 40
Observations in cattle
% observing abortions in their
cattle (obtained from group
discussion) 10 a 27b
19 c 17 a
% observing abortions in their 8 a 21 b 6 a
70
cattle * 14 b
% observing infertile cows in their
cattle
(>2 years without calf) * 2 a 18 b
12 b 10 a
Observations in SR
% observing abortions in their SR
(obtained from group discussion) 20 21
7 26
% observing abortions in their SR
* 12 8
3 14
* Obtained from questionnaires a:b (p<0.05)
Summary:
• The number of cattle herds with infertile cows or abortions was higher in Guinea
and Guinea Bissau than in Senegal and The Gambia
5.8 Serological sampling for brucellosis
5.8.1 B. abortus in herd bulk milk samples
On some farms herd bulk milk samples were taken and tested for B. abortus using
milk-ELISA (Table 38). Bulk milk samples were not collected in the GBA (The
Gambia) and Coyah (Guinea) as most of the herds were on transhumance.during the
time of the study Significantly higher herd prevalences for bovine brucellosis were
found on farms from Guinea and Guinea Bissau confirming previous observations in
serological surveys (see 5.9.1 and Annex 2, Table 1).
Table 38: Serological results for B. abortus for herd bulk milk samples
Gambia Guinea Guinea Bissau Senegal*
Location GBA CRD Bafata Coyah Dubréka MOPS LIPS
No of herds sampled - 20 20 - 12 20 20
% Herds with positive bulk
milk for B. abortus
- 15 a
(3/20)
75 b
(15/20)
- 83 b
(10/12)
10 a
(2/20)
5 a
(1/20)
a:b (p<0.05)
71
5.8.2 B. abortus in man (volunteers)
In a local health centre in Dubréka (Guinea), identified as a high brucellosis
prevalence area for cattle in previous ITC studies (see 5.9.1 and Annex 2, Table 1),
some individuals in the potential risk groups (eight herders, seven farmers, three milk
vendors and two veterinary technicians) were tested for the presence of brucella
abortus antibodies. Out of 20 volunteers seven reacted positive, all of them herders
(n= 4) or farmers (n= 3).
Summary
• B. abortus herd prevalence in bulk herd milk was significantly higher in Guinea
and Guinea Bissau.
• Seven out of 20 volunteers tested positive for brucellosis in a high prevalence
area for cattle (Dubréka, Guinea).
5.9 Differences in local perceptions of the impact of zoonoses on livestock
and
man in relation to present and previous serological findings in cattle
Since 2000 ITC has undertaken several studies to get base line information on the
distribution of bovine brucellosis and tuberculosis in cattle in The Gambia, Senegal,
Guinea and Guinea Bissau. The studies were carried out in the form of abattoir (BTB)
and herd screening surveys (BTB and brucellosis).
5.9.1 Brucellosis
Results of previous serological studies are summarized in Table 1 of Annex 2 and
indicate different epidemiological situations in the four countries. Highest mean
72
prevalences for bovine brucellosis were found in Guinea Bissau (Bafata: 18.6%) and
Guinea with 9.2% (Dubréka and Coyah). These values were considerably lower in
the surveyed districts of The Gambia (CRD: 1.1 %) and Senegal (Bassin Arachidier.
0.6 %). No samples were taken in the GBA of The Gambia.
During the course of this study, herd bulk milk samples were collected from
participating farmers. The results are presented in Section 5.8.1. and are consistent
with previous serological findings.
It was expected that differences in farmers’ and risk groups’ perception of the impact
of brucellosis would be related to the distribution of the infection in cattle. Therefore
the results of the PRA and semi-structured questionnaires were compared with
previous and actual (herd bulk milk) serological findings.
As shown in Table 39, brucellosis was ranked high as a disease by farmers and local
veterinarians in the high prevalence areas of Guinea and Guinea Bissau. Also, in
these countries, clinical symptoms of brucellosis in cattle were more frequently
observed and there was greater familiarity with the disease and its modes of
transmission. However, farmers’ knowledge about the prevention of infection did not
necessarily correlate with serological findings e.g. high herd prevalences were found
in areas with high (Guinea Bissau) as well as in areas with low knowledge (Guinea)..
Despite the different epidemiological situations for brucellosis in cattle and the
observed differences in perception of farmers and veterinary health services, the
awareness of the public health sector for this zoonosis was very low in all four
countries. Currently, no diagnostic tests on patients with brucellosis-like-symptoms
were either performed or available in any of the health centres visited.
Table 39: Respondents’ perceptions of brucellosis and serological findings by
country
Gambia (CRD)
Guinea Guinea Bissau
Senegal
Farmers perceptions (see 5.2.1.1)
Ranking of brucellosis among 5
Most important diseases
Not among
first 5
Rank No.
5
Rank No.
5
Not among
first 5
Ranking of brucellosis among
chronic infections
Not
mentioned
Rank No. 1 Rank No. 1 Not
mentioned
Farmers observation on brucellosis (see 5.4.1)
73
No. of farmers knowing the
symptoms 4/15 30/40 20/20 23/40
No. of farmers knowing the
modes of transmission 3/15 11/40 20/20 22/40
No. of farmers knowing the
preventive measures 2/15 1/40 13/20 9/40
VH authorities’ perceptions (see 5.6.2.2)
Ranking of brucellosis among 5
Most important diseases Not among
first 5
Rank No.
3
Rank No.
4 Not among
first 5
PH authorities, perceptions (see 5.6.3.3)
No. of officers knowing
the zoonotic character 0/3 1/4 1/3 2/4
No. of officers knowing the
diagnostic procedures in man No knowledge 1/4
Serological survey (previous studies, see Annex 2, Table 1)
Mean animal prevalence 1.1 a
(0.2,2.0)
9.2 b
(7.8,10.6) 18.6 c
(15.3,21.9) 0.6 a (0,1.3)
Mean herd prevalence 15 a
(0,30.6)
88.6 b
(78.1,99.0) 100 b 10 a
(0,20.7)
Serological screening of bulk milk (present study, see 5.8.1)
Mean herd prevalence 15 a - 83 b 7.5 a
In brackets: CI for the mean
74
5.9.2 Tuberculosis
Findings obtained from previous on-farm and abattoir ITC investigations into bovine
tuberculosis are summarized in Table 2 of Annex 2. No confirmed cases of M. bovis
were found in any of the countries.
Results are consistent with observations obtained from the PRA and questionnaires
(Table 40) administered in this study. Farmers as well as veterinarians did not
consider BTB to be an important disease. However, farmers’ knowledge of
symptoms in cattle and how to prevent transmission to man was significantly better in
Guinea Bissau. There were no differences in perception of PH authorities. No
confirmed case of BTB was reported in any of the health centres or hospitals visited.
Table 40: Respondents’ perceptions of BTB and serological findings by country
Gambia Guinea Guinea Bissau
Senegal
Farmers’ perceptions (see 5.2.1.1)
Ranking of BTB among 5 most
important diseases
Not mentioned
Ranking of BTB among chronic
infections
Not mentioned
Farmers observation on BTB (see 5.3.1.1 )
No. of farmers knowing the
symptoms 7/35 a 20/40 b 15/20 b 6/40 a
No. of farmers knowing the
preventive measures 2/35 a 1/40 a 15/20 b 4/40 a
VH authorities’ perceptions (see 5.6.2.2)
Ranking of BTB among 5 most
important diseases Not mentioned
PH authorities perception (see 5.6.3.3)
Isolation of M. bovis applied Not applied regularly Not applied
Reports in man No knowledge
Previous surveys – tuberculinization & meat inspection - (see Annex 2, Table 2)
Mean animal prevalence 0 0 0 0
a:b (p< 0.05)
75
Summary:
• Differences observed in perception of farmers and other risk groups concerning
brucellosis (i.e. knowledge and results of disease importance ranking) were in
agreement with serological results for brucellosis in cattle. Brucellosis was
ranked high by farmers and veterinarians in the high risk areas for cattle.
• The absence of BTB infection in cattle was confirmed by a general low perception
of farmers and veterinary health authorities related to this diseases (i.e. not
considered as an important disease in disease ranking)
6 DISCUSSION
This study was the first attempt in each of the four countries to get information on the
impact of zoonoses by obtaining and comparing information from different
stakeholder groups: farmers, milk vendors, butchers, veterinarians, public health
authorities. Information was collected using group discussions and interviews. The
results obtained were compared to previous prevalence studies for selected zoonoses.
Discussion of methodology
The study chose a step-wise approach, starting with group discussions in form of
PRAs with groups of up to 15 people, composed of the key persons dealing with the
animals either directly (farmers and herders) or indirectly (milk vendors). A local
veterinary person (veterinarian or livestock assistant) was also invited to verify
observations and to assist in clarifying local descriptions for ultimate definition of the
most important diseases. It showed that “unspecific symptoms” were difficult to
allocate to individual diseases. We therefore gave specific disease descriptions as
guidelines for the discussion. With this assistance, the PRA group discussions were
able to reach a consensus as to which were the most important diseases, although
some groups of symptoms were retained as such in the ranking (foot problems and
diarrhoea).
76
As would be expected, participants tended to remember recent outbreaks more easily
than events in the past, so questions covered the last 12 months. Replies may also
have been influenced by the lack of knowledge of specific diseases and better
knowledge of disease syndromes such as diarrhoea, constipation, foot problem,
abortions, respiratory problems. It was observed that farmers were not clear about
the difference between anthrax and BQ, particularly in the francophone countries
where their French names are similar (charbon bacterienne and charbon
symptomatique).
The moderators of the PRAs attempted to clarify some of the uncertain answers by
additional questioning and further discussions. This led to allocation of some of these
descriptions to groups of diseases, e.g. respiratory disease allocated to PPR and
pasteurellosis.
The main objective of this study, the importance of zoonoses, was not directly
communicated to the farmers while carrying out the exercise of definition of most
important diseases, in order to assess their appreciation by farmers amongst all other
diseases. One of the PRA discussion points was the knowledge of chronic diseases.
This question was asked with a view to bringing out the mention of brucellosis and
tuberculosis-like disease occurrences. Answers were clearly referring to brucellosis
in Guinea and Guinea Bissau, whereas no reference was made in Gambia and
Senegal. No reference was made to tuberculosis in any of the four countries. In
general, chronic diseases were even less specifically described by farmers than acute
diseases and were difficult to allocate.
Thereafter questions were directed more specifically to zoonotic diseases also in a
step-wise approach: “name up to three zoonotic diseases”; “discuss the top zoonotic
diseases”; “specify your knowledge of these diseases”. It was particularly noticeable
in this discussion that some participants easily dominated others, which could be
explained by the general lack of awareness of what zoonosis, as a concept of a
disease, which people could get from animals, means.
77
Thereafter five farmers from the PRA group were invited to look at the list of
important diseases, including the identified zoonoses and were asked to select the top
five diseases and to rank them (separately for cattle and small ruminants).
In a second step the group of informants was expanded to include selected
farmers/herders, veterinarians, butchers and medical health authorities. The method
used was semi-structured questionnaires. It was observed that willingness of
farmers/herders to go into exhaustive discussions particularly on disease reporting
over the last 12 months was less than during group discussions (PRA), which made it
more difficult e.g. to reach at disease ranking. On the other hand, answers to specific
questions, e.g. on symptoms, mode of transmission of zoonotic diseases, were more
differentiated and more quantitative. The use of questionnaires with the group of
veterinary and medical health personnel posed no problems and revealed clear
results. Interviewing butchers revealed that their record keeping was poor, therefore
answers could not be confirmed by documentation.
In conclusion, this study tried to make use of different approaches so as to
compensate for deficits that may be inbuilt in one method by using additional
methods. However, a certain degree of interpretation by the moderators (PRA) and
interviewers (questionnaires) influenced the final presentation of results. This aspect
has been offset by a multi-facetted presentation of the results that span all approaches
and questions asked. This shows particularly when comparing results of PRA and
individual interviews on brucellosis or farmers’ knowledge of zoonotic diseases in
different countries, where similar results were obtained by both methods.
Zoonoses
This discussion does not attempt to repeat the results reported in each chapter.
Farmers’ perception of zoonoses clearly differed between the countries, with a better
level of knowledge in Guinea Bissau. This observation was initially made during
group discussions and later confirmed in the interviews. The greater knowledge
covered symptoms in animals, mode of transmission and preventive measures, the
78
latter two only for certain zoonoses. Moreover, changes in meat quality due to animal
disease were also better known in Guinea Bissau than in the other three countries.
The differing levels of knowledge seem to be related to how common the disease is
within a country (e.g. prevalence of brucellosis highest in Guinea Bissau, followed by
Guinea). However, this does not fully explain the varying levels of knowledge of
rabies or BTB as the distribution of these diseases is similar in the four countries.
With the exceptions mentioned above for Guinea Bissau, the PRA has clearly
demonstrated that farmers are not aware of the potential risks of consuming meat
from animals suffering from acute or chronic diseases such as anthrax or BTB. In
particular, their knowledge of the public health risk of anthrax was poor. The
majority of respondents in group discussions in The Gambia, Senegal and Guinea
indicated that meat of such animals is consumed after proper cooking or traditional
treatment.
Milk in the region is consumed as fresh and or sour milk. SOMDA et al. (2003) have
shown in a recent survey on the consumption pattern of milk in The Gambia that
local fresh milk is the most preferred (35%) followed by sour milk (33%). Moreover
81% of respondents preferred local dairy products to imported ones Results have
clearly shown that processing of raw milk differs between countries. Milk, if
consumed fresh on farm, was boiled by the majority of farmers in Guinea Bissau,
while in all other countries this is the exception. Although this is applied traditionally
in Guinea Bissau it might be also related to the high prevalence of brucellosis, which
is locally known as “bakale” and related by some farmers to malaria-like symptoms
in man. Conversely a good number of farmers in The Gambia and Senegal still
believe that heating of milk may significantly reduce the yield of the producing cow.
This traditional belief might limit the willingness of these farmers to accept
pasteurisation as measure to prevent the transmission of zoonoses. However, because
of customer preferences, milk is often sold fermented and therefore never boiled.
Farmers and milk vendors clearly believe that milk, if boiled once, will not ferment.
The use of starter cultures for fermentation after heating, was not known to the milk
vendors. Some vendors related faster fermentation to improved quality of milk, an
observation, which might reflect their interest in selling as much as possible sour
79
milk. The same observation was made by HEMPEN (2003). These vendors were thus
not aware of the fact that faster fermentation indicates higher bacterial contamination.
Bovine brucellosis
The key symptoms of bovine brucellosis such as the occurrence of abortions,
hygromas and infertility in cows were more frequently observed in Guinea and
Guinea Bissau. In addition, farmers’ knowledge was better in these two countries.
However, there are important public health implications attached to the observations
made, particularly during group discussions in Guinea, that farmers do not consider
cows with hygroma as sick and their milk is still consumed.
It is well known for brucellosis that seropositivity is strongly related to the
occurrence of this clinical symptom (AKAKPO et al., 1987, OLOFFS 1996,
OLOFFS et al. 1998, UNGER et al, 2003). Therefore it was expected that these
differences in reports of clinical observations may coincide with previous results
from serological surveys. When comparing PRA results and serological findings this
assumption was confirmed. Significantly higher prevalences for bovine brucellosis
based on serology in serum (previous surveys) and herd bulk milk (see 5.8.1) were
found in Guinea Bissau and Guinea as compared to The Gambia and Senegal.
The high prevalences in reported herd bulk milk samples in Guinea and Guinea
Bissau and the volunteers testing serologically positive in Dubréka in Guinea are also
indicative of a high public health risk. However, this high risk was not at all reflected
in any awareness of this disease by the public health authorities. The majority of
public health persons interviewed were not aware of brucellosis as a zoonosis.
Moreover, the capacity to diagnose infections in man was not available in any of the
health centres visited. As confirmed in our investigations in volunteers and also
reported by PERRY et al. (2002) prevalences for brucellosis in risk groups in high
prevalence areas for cattle are likely to be high.
80
It has to be noted that a moderate number of abortions in cattle was also reported by
farmers in The Gambia and Senegal. This indicates that there are other causes than
brucellosis for abortions. In contrast to cattle the occurrence of abortions in small
ruminants did not differ significantly between the countries.
BTB
In contrast to bovine brucellosis, farmers’ awareness of this zoonosis was generally
low in all countries surveyed. This was also confirmed by the veterinary and public
health authorities. The results of group discussions and interviews are in agreement
with previous findings of ITC studies. As no confirmed case of M. bovis was found in
the cattle population in large scale abattoir and on-farm surveys it was concluded that
the risk posed by this zoonosis to the consumer is very low (UNGER et al. 2003).
Although the interviews in hospitals and health centres have shown that M.
tuberculosis is widespread in the region the diagnostic capacity to isolate M. bovis in
human sputum samples is restricted to the National Reference Laboratories (Senegal
and Guinea) and the Medical Research Council (The Gambia). However, the standard
procedure for investigating cases of suspected tuberculosis usually stops after the
Ziehl Neelsen stain without further culturing and can only confirm Mycobacteria spp.
Production system
Results from interviews and group discussions indicated that farmers’ knowledge of
zoonoses was not related to production systems. A possible explanation for this
unexpected result might be that the introduction of the MOPS in the GBA of The
Gambia and the Bassin Arachidier of Senegal is not yet fully established and is an
on-going process. It is better characterised as a transitional phase from LIPS to
MOPS. Therefore, farmers’ knowledge might not yet be significantly different
between the two systems.
81
Results show the urgent need for an improvement of knowledge of farmers
representing the MOPS, as it is well known that the incidence of certain zoonoses
(diseases of intensification) might increase drastically with intensification.
However, some differences in disease ranking were observed between the production
systems for The Gambia. The ecological and endemic situation differs between the
GBA and CRDsouth. Therefore the level of challenge from certain diseases (e.g. tick-
borne diseases or trypanosomosis) varies and could explain the different rankings.
7 CONCLUSIONS
Comparing results obtained from various groups of respondents (farmers, herders,
butchers, milk vendors, veterinarians and public health facilities) and using different
methods of collection of information (interviews and group discussions) this scoping
study was able to collect a significant amount of information on all aspects of
zoonoses. All the potential risk groups (farmers, herders, butchers, milk vendors,
butchers and veterinarians) and health authorities (veterinary and public health) were
involved in the study. This broad-spectrum approach has not been applied before and
can be considered unique.
Furthermore, this scoping study linked results from questionnaires and group
discussions obtained from different groups of respondents with data from
epidemiological studies on the distribution and prevalence of selected zoonoses. It
was clearly shown that serological prevalences of selected zoonoses (bovine
brucellosis and BTB) were reflected in farmers’ perceptions.
For brucellosis, it was shown for two countries of the study region (Guinea and
Guinea Bissau) that the perception of interviewed groups did correspond well with
the prevalence of this zoonosis in cattle, but it did not correlate to the potential
impact in man. Based on results of herd screenings and clinical observations,
brucellosis is considered to be a serious human health hazard in the surveyed districts
in those countries. Although the symptoms of brucellosis in cattle and the possible
modes of transmission to man, were best known by farmers in the high cattle
prevalence area of Guinea Bissau, this improved knowledge did not result in the
82
application of any meaningful control measures, thus it may not contribute to reduced
prevalences in cattle and consequently in man.
In particular the perception of the public health authorities was exceptionally low in
areas with high prevalence in cattle, and equally so in the low prevalence areas of
Guinea and Guinea Bissau.
Livestock offers both a major contribution to the livelihood of producers but also a
risk to consumers´ health and performance. The control of zoonotic diseases such as
brucellosis will require a coordinated effort of medical and veterinary research, the
provision of veterinary services and the reinforcement of disease control regulations.
8 RECOMMENDATIONS 8.1 Recommendations for the control of Bovine Brucellosis in the countries
of this survey
Based on the results of the prevalence studies and perceptions of farmers, the
approach in the fours countries to control of bovine brucellosis differs.
Recommendations are made by country and include the technical options as well as
human resource development options.
8.1.1 Guinea
The scoping study together with the animal prevalence studies revealed the existence
of areas of high within-herd prevalence (up to 13.2, CI: 10.8, 15.6), well above the
limit of 10% recommended by OIE for vaccination. However, areas where no
brucellosis was found were also detected (e.g. Labe) during the prevalence studies.
Given the infrastructure and poor financial situation of public services in Guinea, a
country wide serological survey, though appropriate, can not be recommended.
However, our results give enough evidence to justify intervention. We therefore
recommend that Guinea seeks external donor funding support to carry out surveys in
other Provinces with high cattle densities in form of bulk milk sample testing. Herds
found positive in bulk milk sample tests should then be retested serologically. This
approach is fast, easy to apply and cheaper than large scale serological surveys.
83
Based on the results already available from our studies and the recommended
additional study, the appropriate application of the control option vaccination and test
and slaughter can be made. We recommend for the areas covered by our studies,
vaccination of herds with an within-herd prevalence >10% following OIE procedures
to reduce prevalence to levels that are appropriate for test and slaughter policy.
Similar control attempts in other developing countries (e.g.Malaysia) have not fully
succeeded because between herd movement in high prevalence areas could not be
controlled (Palamisany et al. 2003). An individual animal registration system exists
in Guinea, that could be used to enhance this type of movement control.
Additional measures to break the chain of infection within and between herds are an
increased level of hygienic handling of infectious material (aborted foetus, milk of
positive animals). Our studies showed that these measures are usually not known and
are not applied.
8.1.2 Guinea Bissau
The areas covered in Guinea Bissau by the scoping study and the animal prevalence
study cover more than 50% of the National herd. In all areas surveyed brucellosis
was found to exist with maximum within-herd prevalence of 19.4% (CI: 16.1, 22.7).
It can therefore be concluded that a countrywide effort to control brucellosis is
indicated without necessity for further herd testing.
Given the limited number of the national herd (~ 300.000 cattle) a nationwide
vaccination campaign can be recommended to reduce prevalence to levels
appropriate for test and slaughter. Application of hygienic measures and animal
movement control as described for Guinea apply. However, our study found a
significantly higher knowledge by farmers on possible preventive measure (e.g.
discarding of milk from animals with hygroma or abortion history; destruction of
aborted foetus).
Technical control options recommended for both countries include the test and
slaughter option as per recommendation by OIE.
In both countries cattle represent living capital for herd owners and their agreement
to slaughter animals in case of detected brucellosis may be difficult to obtain unless
84
compensation is offered. This attitude is the major obstacle to implementation of this
control option and Governments should consider to request external financial
assistance not only for the vaccination campaign but also for the creation of a
compensation fund.
8.1.3 Gambia and Senegal
Compared to the findings in Guinea and Guinea Bissau the within-herd prevalence in
the areas surveyed were well below 10% (Senegal: 0.9%; CI: 0; 1.1; Gambia: 0.8; CI:
0;2.)
Gambia: though our study surveyed the District with the highest animal density (40%
of the national herd) we recommend extending the survey to include the other
districts to consolidate our findings using the approach as described above (screening
of bulk milk samples followed by serological tests of positive herds),
Given the low animal prevalence (5 animals out of 465) the test and slaughter
policy is recommended and Government authorities should be encouraged to
reinforce this policy, bearing in mind the necessity to compensate farmers.
Senegal: Contrary to the other countries, the area surveyed in Senegal is not
representative in terms of highest cattle numbers, but represents an area in transition
from traditional to intensified cattle husbandry, where cross bred dairy animals have
been introduced since the 1990s. As brucellosis has often been described as a disease
of intensification, it was seen important to characterise the disease situation in this
region. Other areas with high local cattle densities and small numbers of crossbreds,
e.g.. Casamance, have not been covered by our study and herd testing using bulk milk
samples is recommended.
The same recommendation concerning the test and slaughter policy as described for
Gambia applies.
85
In addition to the above technical control policy option, the study revealed different,
but generally very poor levels of knowledge on zoonoses, their spread, symptoms and
control by the investigated risk groups (farmers, butcher, milk vendors, herders,
public health authorities).
We recommend sensitisation and awareness campaigns and training targeted at the
different groups.
Farmers and herders in Guinea Bissau had the highest level of knowledge. Practical
training in disease control and prevention appears appropriate, whereas for all other
countries sensitisation and awareness campaigns have to precede training.
The group of butchers had the same low level of knowledge in all countries; training
on diseases that affect quality of meat is recommended.
People handling milk (herders, milk vendors) would benefit from training on milk
hygiene and awareness on risk associated with consumption of raw milk.
Public health authorities in all countries had a very low awareness of the importance
of zoonotic diseases, with the exception of rabies. The link between Veterinary health
and Public Health authorities is generally weak, better communication and exchange
of health statistics is recommended.
The recommendations for sensitisation and training should be supported by the
production of leaflets for distribution to livestock assistants and other veterinary and
public health personnel, training manuals to be used for training of farmers and
multimedia campaigns.
8.2 Recommendations for future research
The most surprising finding in the prevalence studies was the apparent non-existence
of BTB in the four countries under investigation. This finding was well reflected in
the perception of livestock stakeholders, who did not attribute any major importance
to BTB. As much as human tuberculosis is on the increase, also in the context of the
AIDS pandemic, there is no apparent zoonotic link to cattle.
During the tuberculinisation tests in Guinea, The Gambia, Guinea Bissau and
Senegal, more than 50% of cattle reacted positive for PPD M. avium. Recent findings
86
have shown that environmental infections with other mycobacteria can influence the
immune response to M. bovis to an unknown extend (BUDDLE et al., 2002;
VORDERMEIER et al., 2001). It is therefore assumed, that the unexpected absence
of M. bovis in the study population may not reflect the true epidemiological picture.
The phenomenon of interference of environmental infections with the classical
infection pathway, explained by cross-immunity mechanism, has been reported in
humans (BLACK et al., 2002). The observed variation in immuno-response to M.
tuberculosis in man may reflect geographic variations in the exposure to
environmental mycobacteria, as it was reported recently by BLACK et al. (2002)
comparing vaccinated populations in Malawi and UK. When tested with the specific
antigen for M. tuberculosis (ESAT -6) in comparison with the PDD, a larger
proportion of patients reacted positively to the PDD, a clear indication for exposure
to environmental mycobacteria. The role of the unspecific, non-pathogenic
mycobacterial infections in the epidemiology of M. bovis is not known and may be
very specific for West Africa. As described for M. tuberculosis (BLACK et al., 2002)
and in consideration of the very close genetic similarity between M. bovis and M.
tuberculosis, potential candidates for protective cross-immunity for M .bovis could be
M. avium. M. intracellulare and M. marinum.
Further investigations using more sensitive diagnostic methods to clarify the role of
possible cross-immunity induced by environmental mycobacteria in the
epidemiology of BTB as well as human tuberculosis are recommended. Results could
provide more differentiated information on the role of mycobacteria infections in
cattle and the role of environmental versus pathogen mycobacteria.
9 ACKNOWLEDGEMENT
The authors would like to thank all the people who actively participated in the
implementation of this study, too many to be named here. Particular thanks go to Dr
Boye Diallo and Dr Alphonse Goumou of Guinea (DNE), Dr Mamadou Diop and Mr
Douda Deh of Senegal (ISRA), Dr Hipolito Djata and Dr Ivo Mendez of Guinea
Bissau (DGP) and Mr Jabel Sowe and Dr Demba Jallow of The Gambia (DLS), who
assisted in the identification of experienced PRA staff, suitable areas to carry out the
87
study and general organisation of this study. The PRA experts, namely Omar Ngom,
Louis Beavogui, Filomeno Barbosa deserve our sincere thanks for their devotion to
this work, even under difficult local circumstances and working conditions.
Support with sample size determination and choice of statistical methods was given
by Dr Moses Kyule, FU Berlin, Germany and Dr Mulumba Kamuanga of
ILRI/CIRDES.
No results could have been presented here without the wholehearted support and
willingness to participate of the farmers that shared their opinions, time and
enthusiasm about livestock keeping with us.
The International Trypanotolerance Centre provided its facilities, infrastructure and
the support by the Director General to this study is acknowledged.
Our colleagues Michaela Hempen and Penda Kane need to be thanked for their
assistance in the milk sample testing. The assistance of Dr Karsten Nöckler
(Reference Laboratory for brucellosis at the Institute for Risk Assessment, BfR,
Berlin, Germany) and Dr Jakob Zinsstag, (Swiss Tropical Institute, Basel,
Swizerland) in providing the antigen and reagents for the serological tests for
brucellosis is greatly appreciated.
We gratefully acknowledge the funding of this study by DFID’s Animal Health
Programme.
88
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AKAKPO, A. J., BORNAREL, P. (1987):
Epidemiology of animal brucellosis in Tropical Africa:
Clinical, serological, and bacteriological surveys.
Res. Sci. Tech. 6, 981-1027.
AKINBAMIJO, O.O. (2003):
Peri-urban/market oriented agriculture: an introduction
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The Gambia. International Trypanotolerance Centre, Banjul, The Gambia,
ISBN 9983 9910 39, 104 pp.
BATHKE, W.(1987):
Brucellose. In: BEER, J.: Infektionskrankheiten der Haustiere.
Gustav Fischer Jena, 3rd, 1987, 654-655.
BUDDLE, B.M., WARDS, B.J., ALDWELL, F.E:, COLLINS, D.M., De
LISLE,G.W. (2002):
Influence of sensitisation to environmental mycobacteria on subsequent
vaccination against bovine tuberculosis.
Vaccine. 2002, 20: 7-8, 1126-1133; 25 ref.
BLACK, G.F., WEIR, R.E., FLOYD, S., BLISS, L., WARNDORFF, D.K.,
CRAMPIN, A.C., NIGWIRA, B., SICHALI, L., NAZARETH, B., BLACKWELL,
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J.M., BRANSON, D., CHAGULUKA, S.D., DONOVAN, L., JARME
N, E., KING, E., FINE, P.E.M., DOCKRELL, H.M. (2002):
BCG induced increase in interferon-gamma response to mycobacgterial
antigens and efficacy of BCG vaccination in Malawi and the UK: two
randomised controlled studies.
The Lancet. Vol 359. April 20, 2002.
DABORN, C.J., GRANGE, J.M., KAZWALA, R.R. (1996):
The bovine tuberculosis cycle – an African perspective.
Soc Appl Bacteriol Symp. 1996, 25, 27-32.
DJORDJEVIC, M., LAKO, B., RISTANOVIC, E. (2003):
The significance of serological tests in diagnosis and following up of
neurobrucellosis: case report.
Poster, Brucellosis 2003 International Research Conference.
Sept 15-17, 2003, University of Navarra, Pamplona, Spain.
DRESCHEL, P., QUANSAH, C. AND PENNING DE VRIES, F. (1998):
Stimulation of urban and peri-urban agriculture in West Africa -
Characteristics, challenges, and need for action. Paper delivered at IDRC
workshop on Urban Agriculture, 15-18 June 1998, Ouagadougou,
International Board for Soil Research and Management and University of
Science and Technology, Kumasi, Ghana, and Bangkok, Thailand, 21 pp.
(June)
FAO (1980) :
Le bétail trypanotolerant en Afrique Occidentale et Centrale, Volume I, Etude
Générale. Etude FAO : Production et Santé Animales 20/1, Rome.
FALL, A. (2003):
Low input livestock agriculture: an introduction
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Proceedings, of the Procordel National Conference, 13-14 November 2003,
The Gambia. International Trypanotolerance Centre, Banjul, The Gambia
.ISBN 9983 9910 39, 104 pp.
GONÇALVES, V.S.P. (1995).
Livestock production in Guinea Bissau: Development potentials and
constraints. PhD dissertation. Department of Agriculture, University of
Reading.
HEMPEN, M., UNGER, F., MUENSTERMANN, S., ZESSIN, K.-H. (2002):
First results of the hygienic status of raw and sour milk from smallholder
dairy farms and local markets and potential risk for public health in The
Gambia, Senegal and Guinea Conakry.
26th International Dairy Foundation World Dairy Congress (Congrilait), Paris,
24 –27.9.2002.
HEMPEN, M. (2003): Personal communications.
MASOURIDOU, S., ANDRIOPOULOS, P., FOKAS, S., KALKANI, M.,
DINOSOPOULOU, M., ASIMAKOPOULOS, G.. TSIRONI, M. (2003):
Presentation of acute brucellosis: A review of 144 cases.
Brucellosis 2003 International Research Conference.
Sep 15-17, 2003, University of Navarra, Pamplona, Spain.
MBOGOH, S.G. (1984):
Dairy development and internal dairy marketing in sub-Saharan Africa:
performance, policies and options. LPU Working Paper No. 5. Addis
Ababa: ILCA.
MDRA/DGP (1991):
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Inquerito sobre os efectivos de gado nas regiões de Oio, Bafata et Gabu.
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Agricultura, Bissau.
NICHOLSON, C.F., RUTHERFORD, A.S., STAAL, S.J., THORPE, W.,
THORTHON, P., KRUSKA, R. (1999):
The impact of income growth and urbanisation on dairy consumption in
developing countries. International Livestock Research Institute, Nairobi,
Kenya.
OLOFFS, A. (1996):
Bovine brucellosis investigations on selected dairy farms in Rukungiri
District and Mukono Country, Uganda.
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Berlin, Germany
OLOFFS, A., BAUMANN, M.P.O., AFEMA, J., NAKAVUMA, J. (1998)
Experiences with a strategy to investigate bovine brucellosis in a rural area in
Southwest Uganda.
Revue Èlev. Méd. Vét. Pays trop., 51 (2), 101-105
PALAMISANY, K., MAHENDRAN, R., IDRIS, K. (2003):
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PERRY, B.D., RANDOLPH, T.F., MCDERMOTT, J.J., SONES, K.R.,
THORNTON, P.K. (2002):
Investing in animal health research to alleviate poverty.
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Baillière Tindall, 4th ed., 1990, 44..
SNOW, B. (2001):
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Environmental Change and the Autonomous Control of Tsetse and
TrypanososMOPSis in Sub-Saharan Africa: The Gambia
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SOMDA, J., KAMUANGA, M., MÜNSTERMANN, S., BITTAYE, A. (2003):
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Gambia: Milk production, marketing and consumption.
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SOMDA, J., KAMUANGA, M., MÜNSTERMANN, S., KEITA, K., MENDES, A..
(2004):
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countries: Economic viability and paths for improvement
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SOW, F., DIOP,M., CISSE, W., MAAL, I., NDIAYE, S. (2003):
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UNGER, F., MÜNSTERMANN, S., GOUMOU, A., APIA, C.N., KONTE, M.,
HEMPEN A. (2003):
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93
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94
11 ANNEX 11.1 Results of this survey
11.1.1 Annex 1a: Guidelines for PRA sessions 1. General information’s (Table)
Village/District/Division
Number of participants (male/female and list where they are from)
Which livestock management do they undertake?
What are the different types of livestock rearing?
2. Which kind of animal health services is available in the area?
How does the service response to your requests (timely, delayed, no
response)?
3. Clinical signs/diseases
• What kind of clinical signs do you observe in your cattle?
Briefly list and describe them
• What kind of livestock diseases do you know?
Briefly list and describe them
• Has there been any outbreak of livestock diseases in the area? (last 3
years)
Cattle/small ruminants and number affected?
Which disease did you assume or describe symptoms if you do not
know the disease?
At what time of the year was it?
4. Long lasting (chronic) diseases
• Do you had/have any cattle in your herd, which suffered for a long time
(more than one month) of any disease?
Cattle/small ruminants and number affected?
Which disease did you assume or describe symptoms?
What do you do with the milk of such an animal?
What do you do if such an animal dies?
95
5. Do you have any animal, which aborted?
What do you do with the aborted foetus?
6. Zoonotic aspects • Do you know any of diseases, which could be transmitted to human
beings?
If yes how is it transmitted and do you know how to avoid
transmission?
• Do you know in your family or on your farm any case of disease, which
could be originated in animals of your farm?
• How do you consume the milk produced at your farm??
How do you sell the milk?
Do you know that some infections are transmitted by milk?
• Do you know that some animal diseases can affect the quality of meat?
If yes which and what did you observe?
What do you think is it possible, that animal diseases can be
transmitted via the meat through man?
If yes, do you now any disease or symptom of such disease?
• Do you visit a doctor when you feel sick or do you use your own
treatment?
7. Selling/buying animals and slaughter management
• Where do you sell or buy your animals?
• What do you do if you slaughter an animal?
Where and how do you slaughter these animals?
Which kind of veterinary services do you use
8. Disease importance ranking:
Depending on the group discussion:
- Information on disease (including wasting diseases)
96
11.1.2 Annex 1b: Tables 1 - 2 and Graphs 1 - 8 Graph 1: Top-ten diseases or symptoms in cattle as ranked by farmers´ in The
Gambia in terms of importance
Graph 2: Top-ten diseases or symptoms in cattle as ranked by farmers´ in
Guinea in terms of importance
2,8
1,8
1,4
1,1 1,00,8
0,7 0,7
0,30,2
0,0
0,5
1,0
1,5
2,0
2,5
3,0
Diarrho
ea
Trypan
o-som
osis
H.S.BQ
FMD
Tick da
mage/
fly so
re
Lumpy
skin
Consti
patio
n
Foot p
roblem
s
Nerveo
us sym
ptoms
Wei
ghte
d av
erag
e
1,9
1,6 1,51,3
1,1 1,1 1,1
0,80,7
0,5
0,0
0,5
1,0
1,5
2,0
2,5
3,0
Diarrho
ea
Lumpy
skin
Foot p
roblem
s
Abortio
n
Hygrom
aH.S.
Anthrax
Tick da
mage/
fly so
re BQW
oula
Wei
ghte
d av
erag
e
97
Graph 3: Top-ten diseases or symptoms in cattle as ranked by farmers´ in
Guinea Bissau in terms of importance
Graph 4: Top-ten diseases or symptoms in cattle as ranked by farmers´ in
Senegal in terms of importance
2,7
1,9
1,61,4 1,4 1,3
1,1
0,80,6
0,4
0,0
0,5
1,0
1,5
2,0
2,5
3,0
BQ
Anthrax
Diarrho
ea
Abortio
nH.S.
Hygrom
a
Mange
Trypan
o-som
osis
Lumpy
skin
Endop
arasit
es
Wei
ghte
d av
erag
e
2,6
2,3
1,6
1,3
0,90,8 0,8 0,8
0,5 0,5
0,0
0,5
1,0
1,5
2,0
2,5
3,0
H.S.
Tick da
mage/
fly so
re
Trypan
o-som
osis
BQ
Diarrho
ea
Emaciati
onFMD
Intox
icatio
n
Mastitis
Abortio
n
Wei
ghte
d av
erag
e
98
Graph 5: Top-ten diseases or symptoms in SR as ranked by farmers´ in The
Gambia in terms of importance
Graph 6: Top-ten diseases or symptoms in SR as ranked by farmers´ in Guinea
in terms of importance
2,7
1,2 1,11,0
0,5 0,4 0,3 0,3 0,3 0,3
0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
Diarrho
ea PPR
Pastore
llosis
Abortio
n
Trypan
o-som
osis
Tympa
nie
Tick da
mage/
fly so
re
Food r
oot
Mange
Skin in
fectio
n
Wei
ghte
d av
erag
e
3,7
0,9 0,80,6
0,4 0,3 0,3 0,2 0,2 0,10
0,5
1
1,5
2
2,5
3
3,5
4
4,5
PPR
Abortio
n
Foot p
roblem
s
Diarrho
ea
Nerveo
us sym
ptoms
Pastore
llosis
Tick da
mage/
fly so
re
Endop
arasit
es
Reduc
ed m
ilk
Intox
icatio
n
Wei
ghte
d av
erag
e
99
Graph 7: Top-ten diseases or symptoms in SR as ranked by farmers´ in Guinea
Bissau in terms of importance
Graph 8: Top-ten diseases or symptoms in SR as ranked by farmers´ in Senegal
in terms of importance
4,3
2,3
1,31,0
0,8 0,7 0,6 0,6 0,4 0,3
0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
PPR
Anthrax
Mange BQ
Trypan
o-som
osis
Tick da
mage/
fly so
re
Diarrho
ea
Pastore
llosis
Abortio
n
Tympa
nie
Wei
ghte
d av
erag
e
2,6
2,0
1,4 1,3
0,80,5 0,5 0,4
0,2 0,10
0,5
1
1,5
2
2,5
3
3,5
4
4,5
PPR
Abortio
n
Pastore
llosis
Tick da
mage/
fly so
re
Foot p
roblem
s
Diarrho
ea
Skin in
fectio
n
Nerveo
us sym
ptoms
Orf
Mange
Wei
ghte
d av
erag
e
100
Table 1: Reports by farmers during group discussions of chronic (long lasting)
diseases in SR
Disease suspected Overall Gambia Guinea Guinea
Bissau
Senegal
Total no of farmers
No. of farmers with SR
suffering from chronic diseases
22 5 8 4 5
Arthritis 1 1
BQ 1 1
Heart water 1 1
Lumpy skin 1 1
Mange 3 1 2
Metritis 1 1
Orf 1 1
Unknown (unspecific symptoms) 13 3 6 - 4
Table 2a: Specific knowledge of rabies and clinical observations in animals
during the last three years by production system and country (% of
farmers)
Rabies Gambia Senegal
F1 local F1 local
Total no farmers 15 20 20 20
Disease & symptoms in animals 67 70 90 95
Modes of transmission 67 45 85 95
Preventive measures 53 35 85 80
Observed in animals* 13 15 10 10
* dogs
101
Table 2b: Specific knowledge of anthrax and clinical observations in animals
during the last three years by production system and country (% of
farmers)
Anthrax Gambia Senegal
F1 local F1 local
Total no farmers 15 20 20 20
Disease & symptoms in animals 40 40 5 15
Modes of transmission 13 25 0 0
Preventive measures 7 25 0 0
Observed in animals* 0 15 0 0
* cattle Table 2c: Specific knowledge of BTB and clinical observations in animals
during the last three years by production system and country (% of
farmers)
BTB Gambia Senegal
F1 local F1 local
Total no farmers 15 20 20 20
Disease & symptoms in animals 13 25 10 20
Modes of transmission 0 15 10 15
Preventive measures 0 10 10 10
Observed in animals* 0 0 0 0
Table 2d: Specific knowledge of bovine brucellosis and clinical observations in
animals during the last three years by production system and country
(% of farmers)
Brucellosis Gambia Senegal
F1 local F1 local
Total no farmers 15 20 20 20
Disease & symptoms in animals 27 20 40 35
Modes of transmission 7 15 10 35
Preventive measures 0 10 10 15
Observed in cattle 0 5 0 0
102
11.2 Results of previous ITC studies on bovine brucellosis and BTB
Table 1: Results of previous serological studies of ITC on bovine brucellosis
carried out in the region
Region Area Cattle sampled
Individual +ve reactors
Individual animal
prevalence in % (CI)
Herds sampled
Herds +ve
Herd prevalence rate in %
(CI) Guinea
Dubréka 749 95/749 12.7 a (10.2,15.2)
17 16 94.1 a (82.9,100)
Coyah 810 48/810 5.9 b (4.3,7.5)
18 15 83.3 a (62.6,100)
Guinea
Bissau
Bafata 539 100/539 18.6 c (15.3,21.9)
15 15 100 a
The Gambia
CRD south 465 5 1.1d
(0.2,2.0) 20 3 15 b
(0,30.6) Senegal
Bassin Arachidier
479 3 0.6 d
(0,1.3) 30 3 10 b
(0,20.7) Superscript letters: Significantly differences between districts
103
Table 2: Results of previous serological studies of ITC on bovine tuberculosis
carried out in the region Results for
M. bovis
The Gambia Guinea Guinea Bissau Senegal
Single meat
inspection
1595 cattle in the GBA
Not applied Not applied Not applied
Suspected positive cases in meat inspection
1 Not applied Not applied Not applied
Confirmed cases of infection*
0 0 0 Not applied
CIDT/meat inspection*
Not applied 933 cattle in Kankan
450 cattle in Bissau
Not applied
Total suspected positive cattle in CIDT**
Not applied 0 2 Not applied
Confirmed in meat inspection
Not applied 0 0 Not applied
CIDT on-farm screening
465 cattle from 20 farms in
the CRD
Not applied Not applied 479 F1 and local cattle from 30 farms in Bassin Arachidier
Herds with suspected positive cattle in CIDT***
3 Not applied Not applied 3
Total suspected positive cattle in CIDT***
5 Not applied Not applied 5
Confirmed positive reactor in CIDT (after retest)
0 Not applied Not applied 0
* Positive in Ziehl Nelson and specific culturing for M. bovis ** Meat inspection of suspected positive reactors to PPD-M. bovis in the CIDT *** Doubtful reaction in skin test
Recommended