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Abstract: We conducted a cross-sectional study from August 2003 to February 2004 to identify risk factors for bovine tuberculosis (BTB) in the Kafue basin of Zambia. We investigated a total of 106 herds of cattle for presence of BTB using the comparative intradermal tuberculin test (CITT) while an interviewer-administered questionnaire was used to gather epidemiological data on herd structure, management and grazing strategies. BTB prevalence at herd level was estimated and possible risk factors were investigated using the multiple logistic regression model. The true herd level prevalence of BTB was estimated at 49.8% (95% CI: 37.9, 61.7%). The logistic regression model showed that cattle herd BTB status was highly associated with area and husbandry practices. When compared to Kazungula, cattle herds in Blue Lagoon were more likely to test positive for BTB when other factors such as management practices were controlled (OR=10.5). In terms of grazing strategies, transhumant herds (TH) had higher odds (OR=3.0) of being positive compared to sedentary herds (OR=1.0). The results in this study provide preliminary information about potential risk factors that were found to be associated with BTB status in cattle. [Copyright &y& Elsevier]

Abstract: Although Cryptosporidium spp. have been associated with diarrhea and mortality in sheep and goats, this is the first study to estimate the prevalence of Cryptosporidium spp. in small ruminants in Southern Africa. Between August 2003 and February 2004, a cross-sectional study with single random sampling was carried out in three Zambian provinces: Central, Southern and Lusaka province. Faecal samples from lambs and goat kids less than 3 months of age were collected and examined using the TechLab Cryptosporidium ELISA. Faecal samples of 257 animals were collected: 152 lambs on 18 farms and 105 goat kids on 13 farms. The prevalence of Cryptosporidium spp. in lambs and goat kids was 12.5% and 4.8%, respectively and 30% of the sheep and goat farms had at least one positive animal at the time of the visit. A subset of the positive samples was withheld for molecular characterisation. Based on sequences obtained after amplification of the 70kDa heat shock protein and the Cryptosporidium 18SrRNA gene, C. parvum was identified in all but one of the animals. In this lamb C. suis was identified. The results of the present study indicate that the animal prevalence in lambs and goats kids is rather low. However, the identification of C. parvum illustrates that small ruminants might be potential reservoir for human infection in Zambia. [Copyright &y& Elsevier]

Abstract: To estimate the prevalence of Cryptosporidium spp. in three different husbandry systems in Zambia, faecal samples were collected from calves up to the age of 3 months. Faecal consistency was scored for correlation with infection. Additionally, 45 positive samples were selected for genotyping by amplification of the 70-kDa heat shock protein (HSP-70) and the 18S rRNA gene. A total of 37 dairy, 25 beef and 92 traditional husbandry farms were visited: 250 samples were collected on dairy farms, 238 on beef farms and 256 on traditional husbandry farms. All samples were analysed using a commercial copro-antigen ELISA (Techlab® Cryptospridium test). The calf prevalence in dairy, beef and traditional husbandry systems was 42.8%, 8.0% and 6.3%, respectively. Furthermore, 75.7% of the dairy farms, 44.0% of the beef farms and 15.2% of the traditional husbandry farms had at least one positive calf at the time of visit. Subsequently, there was a significantly higher Cryptosporidium parvum prevalence on dairy farms compared to beef or traditional farms (χ 2, P <0.001). On dairy farms low faecal consistency was correlated with C. parvum infection (χ 2, P <0.05). Both C. parvum and C. bovis were identified, although in one beef calf C. suis was found. [Copyright &y& Elsevier]