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In a tsetse-infested area of Kenya, we characterised veterinary-drug outlets based on personnel and business characteristics to assess their capacities to provide clinical veterinary services. Structured questionnaires were administered to the retailers and sought information on the characteristics of the owners, salespersons and businesses. A total of 41 retail outlets (20 agro-veterinary, 11 pharmacy, and 10 general shops) were identified. There was poor response to questions on owner characteristics. Proprietors, who had no more than secondary education owned 15 out of 28 shops. Few shops (4/29) were owned by proprietors, who had professional qualifications (in animal health). Most salespersons had only secondary education but no qualifications. Animal-health assistants (AHAs), veterinarians and manufacturer's package inserts (drug leaflets) were the preferred information sources for the retailers. We concluded that drug retailers were poorly equipped with the technical knowledge necessary for drug dispensation and advice.  相似文献   
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A participatory epidemiological (PE) study was carried out with Turkana pastoralists in Turkana South District, Kenya, to determine the relative incidence of livestock diseasess and their impact on livelihoods. A sub-location was used as the sampling unit. A sub-location is the smallest administrative unit and is occupied by clusters of families (called adakars) that share common grazing patterns. A total of 32 sub-locations were randomly selected for the study. At least one focus group discussion involving more than 10 people was held with each adakar. In addition, key informant interviews involving local leaders and animal health service providers were conducted before or after the group sessions. PE techniques that were used with the stock owners include participatory mapping, relative incidence scoring, proportional piling, disease impact matrix scoring, seasonal calendars and probing. The methods used were pre-tested in four sub-locations that were excluded from further study. The study revealed that goats, with median score of 33 (10th and 90th percentiles of 25, 44, respectively) and sheep, median score of 20.5 (15, 26) were perceived to be the most abundant livestock species while goats (median score of 32 [21, 56]) and camels (median score of 22.5 [11, 33]) contributed the most to the livelihoods of the pastoralists. For goats, the overall relative incidence scores of peste des petits ruminants (PPR), contagious caprine pleuropneumonia (CCPP) and mange were 23.5% (15, 34), 25% (21, 45) and 20% (19, 28), respectively. The respective median scores for case fatality rates were 66% (45, 76.5), 62.5% (25, 100) and 73.2% (21.4, 85.7). Disease impact matrix scores indicated that mange was the most important disease of goats. Mange (range: 28–32%) and pox (range: 16–38%) were perceived to be the most prevalent diseases in camels. Livestock movements, limited access to veterinary services and stock theft were identified as key factors that contributed to the high prevalence and persistence of these diseases. This paper discusses strategies that could be used to control these diseases given the challenges associated with nomadic pastoralism and insecurity.  相似文献   
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Common bean (Phaseolus vulgaris L.) is the most important legume crop in Kenya. It is cultivated across a wide range of agro-ecologies which include high potential and marginal areas. Eastern Kenya alone, largely semi-arid, accounts for 35% of the country’s total bean production. Bean farmers mainly small-scale have limited access to quality seed, chemical pesticides and fertilizer. Therefore, bean yield under on-farm conditions still remains below 500 kg ha−1 while the potential is about 1,200 kg ha−1 under semi-arid conditions. To asses the farmers’ views on bean varieties and a key insect pest and associated constraints contributing to yield loss, research was undertaken. The research included survey to quantify the yield loss and Participatory Rural Appraisal to determine the level of adoption and criteria for variety choice in semi-arid eastern Kenya (SAEK). The results show that farmers consider drought and insect pest problems as main causes for low yields. The adoption rate for improved varieties is high but self sufficiency in beans stands at 23% in the dry transitional (DT) agro-ecology and at 18% in the dry mid-altitude (DM) agro-ecology, respectively. This could be attributed to low adaptability since most of the improved varieties grown were selected for high potential areas but now found in marginal areas. Drought, earliness, yield stability, and insect pest resistance are the main reasons for choice of varieties by farmers. Bean fly (Ophiomyia sp.) was identified as one of the key crop pests of beans limiting yield. Besides, African bollworm (Helicoverpa armigera) and bean aphid (Aphis fabae) were ranked higher. Due to limitations of the conventional breeding approach, a participatory plant breeding approach is suggested so as to provide an opportunity to develop insect pest resistant varieties adapted to the SAEK region.  相似文献   
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The primary objective of this study was to assess the impact of Rhipicephalus appendiculatus tick presence (exposure variable) on Theileria parva infection seroprevalence (outcome variable) in a group of cattle belonging to a farm using population attributable fractions (PAF). The analyses were based on a representative sample of 80 traditional smallholder mixed farms. The farms were selected by first stratifying the population administratively and implementing a multistage random sampling in Mbeere district in Kenya. The PAFs were estimated using the stratified, Bruzzi, and sequential partitioned PAF approaches. A secondary objective was, thus, to evaluate the impact of the approaches on the PAF estimates. The stratified and Bruzzi approaches estimated proportion of T. parva infection cases directly attributable to the exposure after controlling for confounding by agro-ecological zone (AEZ). The sequential partitioned PAF approach estimated a PAF associated with exposure after adjusting for any effect that the AEZ may have had by influencing the prevalence of the exposure. All analyses were carried out at the farm level where a farm was classified as infested if the tick was found on cattle on a farm, and infected if at least one animal on a farm was positive for T. parva antibodies. Variance estimation for PAFs was implemented using ‘delete-a-group’ jackknife re-sampling method. The stratified PAF (26.7% [95% CI: 9.0%, 44.4%]) and Bruzzi PAF (26.4% [95% CI: 9.6%, 43.2%]) were consistent in estimating a relatively low impact of farm vector tick presence with a relatively high level of uncertainty. The partitioned PAF (15.5% [95% CI: 1.5%, 29.6%]) suggested that part of the impacts estimated using the stratified PAF and Bruzzi approaches was driven by AEZ effects. Overall, the results suggested that under endemic instability in Mbeere district, (1) presence of R. appendiculatus was not a good indicator of T. parva infection occurrence on a farm; (2) ecological variation could play a role in determining infection impacts. This study provides a preliminary basis for evaluating the potential value and utility of estimating PAFs for variables amenable to control in tick-borne diseases (TBDs) epidemiological studies.  相似文献   
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Point prevalences and animal-level risk factors for Trypanosoma evansi infection were investigated in a cross-sectional study that involved 2227 camels from eastern and central parts of Kenya. The screening tests used were haematocrit centrifugation technique (HCT), mouse inoculation and latex agglutination (Suratex). All camels were screened with HCT, while 396 and 961 of them were, in addition, screened with mouse inoculation and Suratex tests, respectively. Parasitological and Suratex test results were used in parallel to determine the number of camels exposed to T. evansi infections. Statistical analyses were conducted using Statistical Analysis Systems. Parasitological and Suratex test results in parallel were dependent variables in multivariable logistic regression models that determined risk factors for T. evansi infection. Herd-level clustering was corrected with general estimation equations. The prevalences were 2.3% and 19.6%, using parasitological and Suratex tests, respectively, and 21.7% when both tests were used in parallel. There was a positive association between the screening tests (McNemar's test = 104.8, P = 0.001) although the strength of association was low (Kappa = 0.2; 95% CI: 0.1-0.3). Before accounting for herd-level clustering, dry season (OR = 1.5; 95% CI: 1.0, 2.1) and nomadic pastoralism (OR = 1.8; 95% CI: 1.1, 3.2) were associated with increased odds of a camel being exposed to T. evansi infection compared to wet season and ranching, respectively. Following this correction, only nomadic pastoralism was significantly associated (OR = 3.1; 95% CI = 1.0, 14.4) with T. evansi infection compared to ranching. It is concluded that camels managed under nomadic pastoralism had higher risk of being exposed to T. evansi infections than camels from ranching systems of management.  相似文献   
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The effects of drying conditions, final moisture content, and degree of milling on the texture of cooked rice varieties, as measured by texture profile analysis, were investigated. Instrumentally measured textural properties were not significantly (α = 0.05) affected by drying conditions, with the exception of cohesiveness. Cohesiveness was lower in rice dried at lower temperatures (18°C or ambient) than in that dried at the higher commercial temperatures. Final moisture content and degree of milling significantly (α = 0.05) affected textural property values for adhesiveness, cohesiveness, hardness, and springiness; their effects were interdependent. The effects of deep milling were more pronounced in the rice dried to 15% moisture than that dried to 12%. In general, textural property values for hardness were higher and those for cohesiveness, adhesiveness, and springiness were lower in regular-milled rice dried to 15% moisture than in that dried to 12%. In contrast, hardness values were lower and cohesiveness, adhesiveness, and springiness values were higher in deep-milled rice dried to 15% moisture than in that dried to 12% moisture. Deep milling resulted in rice with lower hardness values and higher cohesiveness, adhesiveness, and springiness values.  相似文献   
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Four thousand nine hundred and seventy-one trypanosomosis-surveillance records from an open population of Orma Boran cattle raised under natural trypanosomosis challenge in Galana Ranch, Kenya between the years 1990 and 2000 were analysed. The objective of the analysis was to identify epidemiological factors that influenced time-to-treatment of trypanosomosis cases. Under the surveillance programme, blood was being examined fortnightly for trypanosomosis using buffy coat technique. Infected animals were treated when their packed cell volumes (PCV) fell to 25% or lower. The number of days between the first diagnosis and treatment of trypanosomosis cases was obtained from the difference between diagnosis and treatment dates. Days-to-treatment clustered around the screening periods; therefore, time-to-treatment was represented by a series of time points 0-8 at 14-day intervals. Factors postulated to affect the outcome (time-to-treatment) were age of an animal at time of diagnosis, sex, number of trypanosome infections, trypanosome species and season of the year. Five animal generations were generated from birth dates and treated as nuisance parameters. Conditional logistic regression and Cox proportional hazards models were fitted to the data, the former to analyse factors that influenced treatment after time 0 (outcome dichotomised as time 0 or >0) and the latter to analyse factors that influenced time-to-treatment for cases that were treated after time 0, excluding all cases treated on time 0. The majority of the cases (89.5%) were treated on the same day of diagnosis. Trypanosome infections were more likely to be treated after time 0 in dry than in wet season. Similarly, the rate of treatment was lower in the dry than the wet season. An increase in number of previous trypanosome infections reduced the odds of an animal being treated after time 0. Animals that had been exposed to many infections before had higher rates of treatment than those that had minimal experiences. We offer possible reasons for these observations and conclude that selection of animals for breeding purposes in programmes geared towards improving trypanotolerance should take into consideration the environmental factors that affect classification of an animal as being resistant or susceptible.  相似文献   
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