Livestock farmers' perception and epidemiology of bovine trypanosomosis in Kwale District, Kenya

Livestock Owners' Perception on the Impact of Ghibe-III Hydroelectric Dam on Bovine Trypanosomosis, Southern Ethiopia

BACKGROUND

Trypanosomosis is an endemic livestock disease in Ethiopia. The problem prevails mainly in the South, Southwest, and Northwest regions following main rivers and their tributaries.

METHODS

A cross-sectional questionnaire survey was conducted in Loma and Kindo Didaye districts near the Ghibe-III hydroelectric dam, to compare dam impact upstream and downstream, from January 2019 to June 2020. Two hundred standardized questionnaire surveys were administered. The questionnaire included biography, livestock population before and after dam construction, knowledge of major livestock diseases, clinical signs, transmission, seasonality, and wildlife population status was assessed. Data were analyzed using Mann-Whitney U Test.

RESULTS AND DISCUSSION

A total of 189 questionnaires were returned out of 200 questionnaires administered. Among the respondents, the majorities were males and had an average age of 39.4 + 10.6. In all herd size levels, there was no significant (P > .05) difference before dam construction between the 2 districts; whereas, statistically significant (P < .05) large and medium herd sizes increased by 16%(95% CI: 0.5, 31.5) after dam construction in Loma district; whereas, the same herd size reduced by 20%(95% CI:0,43.7) after dam construction with statistically significant(P < .05) difference. Bovine trypanosomosis ranked first among major diseases. Knowledge of clinical signs, transmission, and seasonality of trypanosomosis was consistent with the literature. 87.8% of respondents in Loma associated reduction of trypanosomosis and tsetse population, but 77% of Kindo Didaye respondents perceived no change in prevalence after dam construction. More reduction in wildlife population was observed upstream than downstream, health services improved, and disease outbreaks and cattle deaths were reduced. Studies in African countries indicate the reduction in tsetse apparent density and absences of wildlife contributed to the reduction of trypanosomosis.

CONCLUSION

An increased herd size, reduced trypanosomosis prevalence, and wildlife population observed upstream, indicate artificial Lake has an impact on tsetse apparent density. Therefore, follow-up of the disease prevalence and investigation of drug resistance is recommended to prove the situation in the study area.

Knowledge, Attitude, and Practice of Livestock Owners and Livestock Assistants towards African Trypanosomiasis Control in The Gambia

Background

In Africa, it has been estimated that 50 million cattle and 70 million sheep and goats are at risk of animal African trypanosomiasis, and three million cattle die annually.

Methods

This study was conducted in all the regions of The Gambia except Kombo Saint Mary Island (Banjul). Structured questionnaires were administered to 440 randomly selected livestock owners and 23 livestock assistants, and 7 focus group discussions were held for both livestock owners and livestock assistants. The data were analyzed mainly using descriptive statistics and content analysis methods.

Results

A total of 94.5% and 75% of livestock owners reported having seen tsetse and horse flies, respectively, while 100% of livestock assistants reported having seen tsetse flies. Forty-seven percent of the livestock owners indicated a positive attitude toward control measures, while 42% of them had no idea how to control tsetse flies. On the other hand, 57% of livestock assistants believe that tsetse and horse flies are the main reasons why AAT is still in their community. There was a statistically significant difference between all the respondents' characteristics and the practices done by livestock owners to prevent AAT vectors from biting their animals.

Conclusion

This study shows that trypanosomiasis is still a major problem for livestock health and production in The Gambia, and it requires disease and vector control.

Prevalence of Trypanosome Species in Cattle Near Ruma National Park, Lambwe Valley, Kenya: An Update From the Historical Focus for African Trypanosomosis

The effective control of diseases in areas shared with wildlife depends on the validity of the epidemiologic parameters that guide interventions. Epidemiologic data on animal trypanosomosis in Lambwe valley are decades old, and the recent suspected outbreaks of the disease in the valley necessitate the urgent bridging of this data gap. This cross-sectional study estimated the prevalence of bovine trypanosomosis, identified risk factors, and investigated the occurrence of species with zoonotic potential in Lambwe valley. The area is ~324 km², of which 120 km² is the Ruma National Park. Blood was sampled from the jugular and marginal ear veins of 952 zebu cattle between December 2018 and February 2019 and tested for trypanosomes using the Buffy Coat Technique (BCT) and PCR-High-Resolution Melting (HRM) analysis of the 18S RNA locus. Risk factors for the disease were determined using logistic regression. The overall trypanosome prevalence was 11.0% by BCT [95% confidence interval (CI): 9.0–13.0] and 27.9% by PCR-HRM (95% CI: 25.1–30.8). With PCR-HRM as a reference, four species of trypanosomes were detected at prevalences of 12.7% for T. congolense savannah (95% CI: 10.6–14.8), 7.7% for T. brucei brucei (CI: 6.0–9.4), 8.7% for T. vivax (CI: 6.9–10.5), and 1.3% for T. theileri (CI: 0.6–2.0). About 2.4% of cattle had mixed infections (CI: 1.4–3.41). No human-infective trypanosomes were found. Infections clustered across villages but were not associated with animal age, sex, herd size, and distance from the park. Approximately 85% of infections occurred within 2 km of the park. These findings add to evidence that previous interventions eliminated human trypanosomosis but not bovine trypanosomosis. Risk-tailored intervention within 2 km of Ruma Park, especially in the north and south ends, coupled with stringent screening with molecular tools, could significantly reduce bovine trypanosomosis.

Farmer perceptions and willingness to pay for novel livestock pest control technologies: A case of tsetse repellent collar in Kwale County in Kenya

Tsetse-transmitted Animal African Trypanosomosis (AAT) is one of the most important constraints to livestock development in Africa. Use of trypanocides has been the most widespread approach for the management of AAT, despite the associated drug resistance and health concerns associated with drug metabolites in animal products. Alternative control measures that target tsetse fly vectors of AAT, though effective, have been hard to sustain in part because these are public goods applied area-wide. The International Centre of Insect Physiology and Ecology (icipe) and partners have developed and implemented a novel tsetse repellent collar (TRC) applied on animals to limit contact of tsetse flies and livestock, thereby reducing AAT transmission. The TRC has now advanced to commercialization. A household-level survey involving 632 cattle keeping households, was conducted in Shimba Hills region of Kwale County, where field trials of the TRC have been previously conducted to assess farmers’ knowledge, perception, and practices towards the management of tsetse flies, their willingness to pay (WTP) for the TRC, and factors affecting the WTP. Almost all the respondents (90%) reported that tsetse flies were the leading cattle infesting pests in the area. About 22% of these correctly identified at least four AAT clinical signs, and even though many (68%) used trypanocidal drugs to manage the disease, 50% did not perceive the drug as being effective in AAT management (50%). Few respondents (8%) were aware of the harmful effects of trypanocidal drugs. About 89% of the respondents were aware of icipe TRC, and 30% of them were using the field trial collars during the survey. Sixty-three (63%) of them were willing to pay for the TRC at the same cost they spend treating an animal for AAT. On average farmers were willing to pay KES 3,352 per animal per year. Male educated household heads are likely to pay more for the TRC. Moreover, perceived high AAT prevalence and severity further increases the WTP. Wider dissemination and commercialization of the herd-level tsetse control approach (TRC) should be encouraged to impede AAT transmission and thus enhance food security and farm incomes among the affected rural communities. Besides the uptake of TRC can be enhanced through training, especially among women farmers.

Animal African Trypanosomosis is a tropical disease that is of economic importance in Sub-Saharan Africa. The livestock sub-sector supports approximately 600 million smallholders in developing countries through employment, income from livestock products, and improving crop productivity through draft power and manure. Efforts to reduce rural poverty and improve food security and nutrition, therefore, require utilizing livestock to their full potential. Trypanosomosis results in anemia, emaciation, productivity loss, and mortality, and remains a leading constraint to livestock development in Africa. To reduce the risks associated with the use of trypanocides, alternative control measures that target the vector- tsetse fly need to be developed and widely disseminated. The International Centre of Insect Physiology and Ecology (icipe) and partners have—developed and implemented a novel tsetse repellent collar that shields animals from getting into contact with the vector, thereby preventing trypanosomosis transmission. The collar has now advanced to a commercialization stage. We conducted community and household-level surveys to assess farmer’s knowledge, perception, and practices regarding tsetse pest and trypanosomosis, and their willingness to pay for the novel tsetse repellent collar. We found that the pest is the main cattle production constraint and the cause of the associated disease, although there exists a gap in the identification of the clinical signs of the disease. Besides, most farmers rely on trypanocidal drugs for the treatment of their animals despite their human health and environmental risks. However, the majority were willing to buy the newly developed canvas collar. A male head of a household with a higher level of education is likely to pay more for the novel tsetse repellent collar. Besides, perception of high prevalence and severity of AAT is likely to increase the willingness to pay for the herd-level technology. The findings emphasize the need for wider dissemination and commercialization of the tsetse repellent collar technology to reduce trypanosomosis transmission and hence enhance food security and farm incomes in the affected regions in Africa.

Prioritizing smallholder animal health needs in East Africa, West Africa, and South Asia using three approaches: Literature review, expert workshops, and practitioner surveys

Managing the health needs of livestock contributes to reducing poverty and improving the livelihoods of smallholder and pastoralist livestock keepers globally. Animal health practitioners, producers, policymakers, and researchers all must prioritize how to mobilize limited resources. This study employed three approaches to prioritize animal health needs in East and West Africa and South Asia to identify diseases and syndromes that impact livestock keepers. The approaches were a) systematic literature review, b) a series of expert workshops, and c) a practitioner survey of veterinarians and para-veterinary professionals. The top constraints that emerged from all three approaches include endo/ ectoparasites, foot and mouth disease, brucellosis, peste des petits ruminants, Newcastle disease, and avian influenza. Expert workshops additionally identified contagious caprine pleuropneumonia, contagious bovine pleuropneumonia, mastitis, and reproductive disorders as constraints not emphasized in the literature review. Practitioner survey results additionally identified nutrition as a constraint for smallholder dairy and pastoralist small ruminant production. Experts attending the workshops agreed most constraints can be managed using existing veterinary technologies and best husbandry practices, which supports a shift away from focusing on individual diseases and new technologies towards addressing systemic challenges that limit access to veterinary services and inputs. Few research studies focused on incidence/ prevalence of disease and impact, suggesting better incorporation of socio-economic impact measures in future research would better represent the interests of livestock keepers.

Community-led data collection using Open Data Kit for surveillance of animal African trypanosomiasis in Shimba hills, Kenya

Objective

In Sub-Saharan Africa, there is an increase in trypanosome non-susceptibility to multiple trypanocides, but limited information on judicious trypanocide use is accessible to smallholder farmers and agricultural stakeholders in disease endemic regions, resulting in widespread multi-drug resistance. Huge economic expenses and the laborious nature of extensive field studies have hindered collection of the requisite large-scale prospective datasets required to inform disease management. We examined the efficacy of community-led data collection strategies using smartphones by smallholder farmers to acquire robust datasets from the trypanosomiasis endemic Shimba hills region in Kenya. We used Open Data Kit, an open-source smartphone application development software, to create a data collection App.

Results

Our study provides proof of concept for the viability of using smartphone Apps to remotely collect reliable large-scale information from smallholder farmers and veterinary health care givers in resource poor settings. We show that these datasets can be reliably collated remotely, analysed, and the findings can inform policies that improve farming practices and economic wellbeing while restricting widespread multi-drug resistance. Moreover, this strategy can be used to monitor and manage other infectious diseases in other rural, resource poor settings.

Electronic supplementary material

The online version of this article (10.1186/s13104-019-4198-z) contains supplementary material, which is available to authorized users.

A cross-sectional study on the use and misuse of trypanocides in selected pastoral and agropastoral areas of eastern and northeastern Tanzania

Background

Tsetse-borne African animal trypanosomosis (AAT) greatly influences livestock distribution and significantly slows livestock productivity in sub-Saharan Africa. While a number of control methods targeting the vector tsetse are in field application, treatment with the few available trypanocides continues to be the most widely applied control method. Unfortunately, improper and frequent use of these few available drugs, accelerated by poor veterinary service delivery, promotes trypanosome drug resistance, the magnitude of which has not been delineated. In the present study, current practices on trypanocide application for the control of bovine trypanosomosis in the field in Tanzania were studied with a view to providing policy advice on the safe and sustainable use of trypanocides.

Methods

A cross-sectional study was conducted using a semi-structured questionnaire administered to a total of 200 randomly selected livestock keepers in selected pastoral and agropastoral areas within three districts in eastern and north eastern Tanzania.

Results

In total, 50% of respondents in all three study districts had primary level education; over 40% had informal education and only 5% with university education (all from one district, Pangani). Age-wise, most respondents were aged 30–59 years with exception of Korogwe where 35% were aged 20–29 years. Over 95% of respondents had knowledge on tsetse as a vector of trypanosomosis and correctly identified tsetse in provided pictures. Furthermore, 98.7% of the respondents applied pyrethroids for vector control. Regarding parasite control practices, this study revealed a high degree of variation in trypanocides usage and the intervals of their application. Whereas only 20% of respondents use chemoprophylaxis for trypanosomosis control, the majority (69–95%) wrongly use diminazene aceturate thinking it is prophylactic, while only 5–30% used the prophylactic drug isometamidium chloride. Most of the respondents (95% in Korogwe, 60% in Pangani and 93.1% in Mvomero) administered the drugs on their own. Improper trypanocides administration was high as respondents in Korogwe (75%) and Mvomero (72%) administered the drugs intravenously with a view to achieving faster drug effect contrary to manufacturers’ recommendations, while 40% of respondents from Pangani used both intravenous and intramuscular routes. Additionally, respondents did not observe the recommended withdrawal periods for the drugs.

Conclusions

This study revealed a high level of trypanocides misuse which poses a high risk of trypanosome drug resistance development as well as risks to human health from drug residues in consumed animal products. This calls for improvements in veterinary service delivery in pastoral and agropastoral areas of Tanzania to counteract the misuse of chemotherapeutics.

Electronic supplementary material

The online version of this article (10.1186/s13071-017-2544-3) contains supplementary material, which is available to authorized users.

Comparative evaluation of the nested ITS PCR against the 18S PCR-RFLP in a survey of bovine trypanosomiasis in Kwale County, Kenya

We compared the nested internal transcribed spacer (ITS) PCR and the 18S PCR-RFLP (restriction-fragment length polymorphism) pan-trypanosome assays in a cross-sectional survey of bovine trypanosomiasis in 358 cattle in Kwale County, Kenya. The prevalence of trypanosomiasis as determined by the nested ITS PCR was 19.6% (70/358) and by 18S PCR-RFLP was 16.8% (60/358). Of the pathogenic trypanosomes detected, the prevalence of Trypanosoma congolense and Trypanosoma vivax was greater than that of Trypanosoma simiae The nested ITS PCR detected 83 parasite events, whereas the 18S PCR-RFLP detected 64; however, overall frequencies of infections and the parasite events detected did not differ between the assays (χ(2) = 0.8, df = 1, p > 0.05 and χ(2) = 2.5, df = 1, p > 0.05, respectively). The kappa statistic (0.8) showed good agreement between the tests. The nested ITS PCR and the 18S PCR-RFLP had comparable sensitivity, although the nested ITS PCR was better at detecting mixed infections (χ(2) = 5.4, df = 1, p < 0.05).

Adherence to the Food and Agricultural Organization guidelines on trypanocide usage among cattle farmers in Itezhi tezhi, Central Zambia

Trypanocides will continue to play an important role in the control of tsetse fly transmitted trypanosomosis now and in the near future. The drugs are mostly administered by farmers without any veterinary supervision leading to misuse and under dosing of medication, and these could be factors that promote trypanocidal drug resistance (TDR) development. In order to delay or prevent TDR, the Food and Agriculture Organization (FAO) recommended guidelines on trypanocide use. It is not known if these recommended guidelines are adhered to in Itezhi tezhi district of Zambia. A survey was undertaken to examine how socio-economic and environmental factors were associated with adherence to the recommended guidelines on trypanocide use in Itezhi tezhi, Central Zambia. Ninety farmers who use trypanocides were interviewed using a questionnaire to collect their socio-economic characteristics (age, education in years, cattle herd size, competence on trypanocide use and their access to extension on trypanocide use) and trypanocide usage practices while crush pens which they use were stratified according to location, whether in the Game Management Area (GMA) (Mutenda, Itumbi, Kapulwe and Banachoongo) or non-GMA (Iyanda, New Ngoma and Shinampamba) as an environmental factor. Associations and measures of associations to adherence of FAO guidelines were determined. The results showed that 25.6% of the farmers adhered to guidelines by FAO on trypanocide use and that none of the socio-economic factors under investigation were significantly associated with it. Further the farmers that used crush pens that were in the GMA had an 80% reduction in the likelihood of adhering to the FAO guidelines on trypanocide use than those that used crush pens in the non-GMA (AOR 0.20, 95% CI: 0.05-0.81, P=0.02). There was low adherence to the recommended FAO guidelines on trypanocide use and it was associated with the location of the crush pen whether in the GMA or not, as an environmental factor. With farmers in the GMA less likely to adhere to FAO guidelines than those in the non-GMA, we recommend an integrated approach of measures to control trypanosomosis in the GMA of Itezhi tezhi to lessen overuse of trypanocides by the farmers.

Infection with the secondary tsetse-endosymbiont Sodalis glossinidius (Enterobacteriales: Enterobacteriaceae) influences parasitism in Glossina pallidipes (Diptera: Glossinidae)

The establishment of infection with three Trypanosoma spp (Gruby) (Kinetoplastida: Trypanosomatidae), specifically Trypanosoma brucei brucei (Plimmer and Bradford), T. b. rhodesiense (Stephen and Fatham) and T. congolense (Broden) was evaluated in Glossina pallidipes (Austen) (Diptera: Glossinidae) that either harbored or were uninfected by the endosymbiont Sodalis glossinidius (Dale and Maudlin) (Enterobacteriales: Enterobacteriaceae). Temporal variation of co-infection with T. b. rhodesiense and S. glossinidius was also assessed. The results show that both S. glossinidius infection (χ(2)= 1.134, df = 2, P = 0.567) and trypanosome infection rate (χ(2)= 1.85, df = 2, P = 0.397) were comparable across the three infection groups. A significant association was observed between the presence of S. glossinidius and concurrent trypanosome infection with T. b. rhodesiense (P = 0.0009) and T. congolense (P = 0.0074) but not with T. b. brucei (P = 0.5491). The time-series experiment revealed a slight decrease in the incidence of S. glossinidius infection with increasing fly age, which may infer a fitness cost associated with Sodalis infection. The present findings contribute to research on the feasibility of S. glossinidius-based paratransgenic approaches in tsetse and trypanosomiasis control, in particular relating to G. pallidipes control.

Farmers' perception of impacts of bovine trypanosomosis and tsetse fly in selected districts in Baro-Akobo and Gojeb river basins, Southwestern Ethiopia

BACKGROUND

Trypanosomosis, via causing anaemia, emaciation, production loss and death, is arguably the most important constraint to livestock development in Sub-Saharan countries, including Ethiopia and its impact in Baro-Akobo and Gojeb river basins (endemic areas for tsetse flies) is unknown. This study was carried out from November 2011 to April 2012 to assess farmers' perception on the presence, impact, management and the need of intervention programs of bovine trypanosomosis and tsetse fly in selected districts located in Baro-Akobo and Gojeb river basins, Southwestern Ethiopia. A standardized questionnaire survey was employed to collect the relevant information from the farmers.

RESULTS

The result of this study showed that 94.1% of the respondents considered bovine trypanosomosis as an economically important cattle disease which accounted for 64.6% of the total annual deaths in the year 2011/2012. Estimated mean annual financial loss via mortality due to trypanosomosis was reported to be 3501 Ethiopian Birr (US$200)/household. The reported trypanosomosis suggestive signs were consistent with published reports and farmers strongly associated the occurrence of the disease with biting flies (particularly, tsetse fly). Respondents also explained that the seasonality of the disease and its vectors, i.e. May and June are peak risk months of the year. Chemotherapy was reported the major method to combating the problem, mean frequency of treatment being 5.7 times per animal per year. Because of the economic burden of the disease, farmers expressed their strong interest and support for the establishment of intervention program in their area.

CONCLUSION

The study revealed that livestock keepers are familiar with bovine trypanosomosis and its vectors as well as its impacts. Thus, trypanosomosis and tsetse control strategies should be integrated with the local communities' participation to minimize the impacts of the disease and its vectors in the area.

Evaluating the potential for the environmentally sustainable control of foot and mouth disease in Sub-Saharan Africa

Strategies to control transboundary diseases have in the past generated unintended negative consequences for both the environment and local human populations. Integrating perspectives from across disciplines, including livestock, veterinary and conservation sectors, is necessary for identifying disease control strategies that optimise environmental goods and services at the wildlife-livestock interface. Prompted by the recent development of a global strategy for the control and elimination of foot-and-mouth disease (FMD), this paper seeks insight into the consequences of, and rational options for potential FMD control measures in relation to environmental, conservation and human poverty considerations in Africa. We suggest a more environmentally nuanced process of FMD control that safe-guards the integrity of wild populations and the ecosystem dynamics on which human livelihoods depend while simultaneously improving socio-economic conditions of rural people. In particular, we outline five major issues that need to be considered: 1) improved understanding of the different FMD viral strains and how they circulate between domestic and wildlife populations; 2) an appreciation for the economic value of wildlife for many African countries whose presence might preclude the country from ever achieving an FMD-free status; 3) exploring ways in which livestock production can be improved without compromising wildlife such as implementing commodity-based trading schemes; 4) introducing a participatory approach involving local farmers and the national veterinary services in the control of FMD; and 5) finally the possibility that trans frontier conservation might offer new hope of integrating decision-making at the wildlife-livestock interface.

Wolbachia, Sodalis and trypanosome co-infections in natural populations of Glossina austeni and Glossina pallidipes

BACKGROUND

Tsetse flies harbor at least three bacterial symbionts: Wigglesworthia glossinidia, Wolbachia pipientis and Sodalis glossinidius. Wigglesworthia and Sodalis reside in the gut in close association with trypanosomes and may influence establishment and development of midgut parasite infections. Wolbachia has been shown to induce reproductive effects in infected tsetse. This study was conducted to determine the prevalence of these endosymbionts in natural populations of G. austeni and G. pallidipes and to assess the degree of concurrent infections with trypanosomes.

METHODS

Fly samples analyzed originated from Kenyan coastal forests (trapped in 2009-2011) and South African G. austeni collected in 2008. The age structure was estimated by standard methods. G. austeni (n=298) and G. pallidipes (n= 302) were analyzed for infection with Wolbachia and Sodalis using PCR. Trypanosome infection was determined either by microscopic examination of dissected organs or by PCR amplification.

RESULTS

Overall we observed that G. pallidipes females had a longer lifespan (70 d) than G. austeni (54 d) in natural populations. Wolbachia infections were present in all G. austeni flies analysed, while in contrast, this symbiont was absent from G. pallidipes. The density of Wolbachia infections in the Kenyan G. austeni population was higher than that observed in South African flies. The infection prevalence of Sodalis ranged from 3.7% in G. austeni to about 16% in G. pallidipes. Microscopic examination of midguts revealed an overall trypanosome infection prevalence of 6% (n = 235) and 5% (n = 552), while evaluation with ITS1 primers indicated a prevalence of about 13% (n = 296) and 10% (n = 302) in G. austeni and G. pallidipes, respectively. The majority of infections (46%) were with T. congolense. Co-infection with all three organisms was observed at 1% and 3.3% in G. austeni and G. pallidipes, respectively. Eleven out of the thirteen (85%) co-infected flies harboured T. congolense and T. simiae parasites. While the association between trypanosomes and Sodalis infection was statistically significant in G. pallidipes (P = 0.0127), the number of co-infected flies was too few for a definite conclusion.

CONCLUSIONS

The tsetse populations analyzed differed in the prevalence of symbionts, despite being sympatric and therefore exposed to identical environmental factors. The density of infections with Wolbachia also differed between G. austeni populations. There were too few natural co-infections detected with the Sodalis and trypanosomes to suggest extensive inter-relations between these infections in natural populations. We discuss these findings in the context of potential symbiont-mediated control interventions to reduce parasite infections and/or fly populations.

Trypanosomosis: a priority disease in tsetse-challenged areas of Burkina Faso

Trypanosomosis is an important disease affecting humans as well as animals. It remains a big constraint to livestock productions in tropical areas. The objective of this study was to assess the importance of trypanosomosis among cattle diseases in Burkina Faso, mainly in tsetse-challenged areas, and to capture information on how farmers apply available methods for controlling the disease. A survey has been carried out in 29 villages of Burkina Faso in three regions (north, southwest, and west regions). One hundred and thirty-four cattle breeders were interviewed individually with a questionnaire. The results indicate that among the 16 diseases mentioned by cattle breeders, trypanosomosis is the most important one in tsetse-challenged areas. Overall, 76.12 % of the breeders mentioned it as the most important disease, while 54.55 % of the farmers in the southwest region and 70.91 % of the farmers in the west region ranked it as a priority disease. Chemoprophylaxis/chemotherapy is widely used as a control method. Isometamidium chloride and diminazene aceturate were used by 53.49 and 46.52 % of the responders, respectively. Among farmers, 85.55 % ranked diminazene aceturate as the less efficient while 14.45 % ranked isometamidium chloride as the most efficient trypanocid. Trypanocidal drug quality and drug resistance were raised as a major concern by 30.77 and 50 % of the respondents, respectively. According to them, zebu cattle are more susceptible to trypanosomosis than taurine Baoule cattle and their crosses with zebu, emphasizing that crossing susceptible breeds with trypanotolerant ones, could be used as part of an integrated control strategy.

Characterisation and validation of farmers' knowledge and practice of cattle trypanosomosis management in the cotton zone of West Africa

We carried out a knowledge, attitude, practice (KAP) survey on how farmers (n=895) manage cattle trypanosomosis in Burkina Faso, Mali and Guinea. Most farmers (96%) recognised the common signs of trypanosomosis, 70% knew the role of tsetse flies in transmitting the disease and 96% had knowledge of drugs used for treatment. Farmers reported that trypanosomosis was the most important cattle disease and estimated that 25% of their herd fall sick each year and 18% of the sick animals die. Nearly all sick animals (90%) were treated with trypanocides and most treatments were administered by untrained farmers. Giving drugs was the strategy most used as primary means of protection (50% of farmers) followed by avoiding high risk areas (32% of farmers) and keeping trypanotolerant cattle (7% of farmers). Few farmers knew about communal tsetse control methods and those who did, rarely practiced them. Farmer diagnosis of trypanosomosis in cattle presented at clinics (n=113) was in most cases (84%) supported by laboratory tests. However, the signs that most farmers considered indicative of trypanosomosis (staring coat and emaciation) were poor predictors of trypanosomosis. We tested farmer knowledge of injection sites and trypanocide dilutions (n=423 cattle), and while few (15%) farmers gave under-dosages or over-dosage (2% of farmers), injection techniques were poor with injection-related side effects in 24% of cattle treated by farmers. Despite this, therapeutic outcomes were both objectively (clinical parameters) and subjectively (carer assessment) satisfactory in 89% of cattle treated by farmers. This study found that farmers play a major role in successfully managing trypanosomosis and recommends the recognition and support for community based treatment.

Endemic type of animal trypanosomiasis is not associated with lower genotype variability of Trypanosoma congolense isolates circulating in livestock

In order to verify whether the low impact on livestock production in endemic areas is related to a low number of trypanosome strains circulating in livestock, 37 Trypanosoma congolense isolates collected from cattle in 11 sites in an endemic trypanosomiasis area in Eastern Zambia were characterised for genotype variability using a modified amplified fragment length polymorphism technique (AFLP). Isolates were further cloned to evaluate the occurrence of mixed infections in individuals. The results obtained revealed a high genotype diversity (94.6%) among these isolates. Apart from one site, all isolates gave different AFLP profiles in each of the sites. When clones were compared, three (8%) of the 37 isolates had mixed infections. These results indicate the circulation of a high number of strains in this trypanosomiasis endemic area despite the low impact the disease has on livestock production.