Bovine tuberculosis (bTB) is an important disease for dairy productivity, as well as having the potential for zoonotic transmission. Previous prevalence studies of bTB in the dairy sector in central Ethiopia have suggested high prevalence, however, they have been limited to relatively small scale surveys, raising concerns about their representativeness. Here we carried out a cross sectional one-stage cluster sampling survey taking the dairy herd as a cluster to estimate the prevalence of bTB in dairy farms in six areas of central Ethiopia. The survey, which to date is by far the largest in the area in terms of the number of dairy farms, study areas and risk factors explored, took place from March 2016 to May 2017. This study combined tuberculin skin testing and the collection of additional herd and animal level data by questionnaire to identify potential risk factors contributing to bTB transmission. We applied the single intradermal cervical comparative tuberculin (SICCT) test using >4mm cut-off for considering an individual animal as positive for bTB; at least one reactor animal was required for a herd to be considered bTB positive. Two hundred ninety-nine dairy herds in the six study areas were randomly selected, from which 5,675 cattle were tested. The overall prevalence of bTB after standardisation for herd-size in the population was 54.4% (95% CI 48.7–60%) at the herd level, and it was 24.5% (95% CI 23.3–25.8) at the individual animal level. A Generalized Linear Mixed Model (GLMM) with herd and area as random effect was used to explore risk factors association with bTB status. We found that herd size, age, bTB history at farm, and breed were significant risk factors for animals to be SICCT positive. Animals from large herds had 8.3 times the odds of being tuberculin reactor (OR: 8.3, p-value:0.008) as compared to animals from small herds. The effect of age was strongest for animals 8–10 years of age (the oldest category) having 8.9 times the odds of being tuberculin reactors (OR: 8.9, p-value:<0.001) compared to the youngest category. The other identified significant risk factors were bTB history at farm (OR: 5.2, p-value:0.003) and cattle breed (OR: 2.5, p-value: 0.032). Our study demonstrates a high prevalence of bTB in central Ethiopia but with a large variation in within-herd prevalence between herds, findings that lays an important foundation for the future development of control strategies.

A cross-sectional survey was carried out to investigate the seroprevalence of ovine and bovine brucellosis in the livestock-wildlife interface area of Nechisar National Park, Ethiopia. Furthermore, producer's knowledge about brucellosis and its zoonotic potential was assessed using a structured questionnaire. A total of 268 cattle and 246 goat sera were collected from 50 herds and 46 flocks and subjected to Rose Bengal test (RBT) and enzyme-linked immunosorbent assay (ELISA) in parallel to detect anti-Brucella species antibodies. Positive reactions were further confirmed with compliment fixation test (CFT). Flock and herd level seroprevalence rate was 12.8% (95% CI 4.8-25.7) and 32.0% (95% CI 19.5-46.7) in goats and cattle, respectively. An overall animal-level seroprevalence of 4.5% (95% CI 2.25-7.86) and 9.7% (95% CI 6.44-13.89) was recorded for goats and cattle, respectively. Seroprevalence showed an increasing trend with age, where adult cattle > 2 years. Goats (> 1 year) recorded relatively higher seroprevalence, but the differences were not statistically significant. Similarly, female cattle and goats recorded a relatively higher seroprevalence, 11 and 5.6%, respectively, compared to males but the difference was not significant. However, a significant (P < 0.01) variation of seroprevalence was noted for parity (bovine), higher in animals in second parity, and abortion history, in both species, higher in animals that experienced abortion. Interviews revealed lack of awareness about brucellosis and food safety related to the zoonotic potential from consuming raw animal products (milk and meat). Ninety-eight percent of respondents did not consider handling abortion material is risky, and only a very low proportion (8%, n = 50) was able to mention limited zoonotic diseases (anthrax and Taenia cysticercosis) could be transmissible to people. The study indicated that brucellosis is endemic in domestic animals in the interface area and calls for further broad epidemiological investigation of the disease in livestock, human and wildlife following 'one health' unified research approaches beside enhancing public awareness.

Background: Abortion is considered an important disease problem of small ruminants in Borana pastoral area. A cross-sectional study was conducted to estimate the prevalence and risk factors of chlamydiosis, coxiellosis (Q-fever) and brucellosis in small ruminants in selected districts of Borana zone. Results: A total of 506 sheep and goats were tested using serological tests. Fifty (9.88%; 95% CI: 7.42, 12.82), 144 (28.46%; 95% CI: 24.56, 32.61) and none (0.00%; 95% CI: 0.00, 0.59) of them were positive for chlamydiosis, coxiellosis and brucellosis, respectively. History of abortion was recorded in 136 (32.00%; CI: 27.59, 36.67) of sheep and goats in the study area. The logistic regression analysis, however, showed that statistically significant difference ccurred among districts and between the species of small ruminants. The prevalence odd of antibodies against C. abortus was significantly lower in Miyo, Dire and Teltelle districts compared to Dillo. The odd of infection with this bacterium was lower in sheep than goats. Similarly the odd of infection with C. burnettii was significantly higher in Dillo district than the rest of the districts studied, higher in goats than sheep and higher in adult animals than young ones. Conclusion: High prevalence of abortion is observed in sheep and goats in the study area. High seropositivity of C. burnetii and C. abortus in both sheep and goats tested implies risks of human infection by both diseases. Thus, attention needs to be paid to further study of both diseases in animals and humans in the area.

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Background: Bovine viral diarrhea, caused by bovine viral diarrhea virus (BVDV), has been considered a disease of cattle but is now emerging in camels. In Ethiopia it has been detected in exotic and cross-bred dairy cattle but no information is available on its occurrence in indigenous cattle breeds and camels. This study was, therefore, conducted to estimate the prevalence of BVDV infection in indigenous Borana cattle and camels (Camelus dromedarius) in Moyale and Miesso pastoral districts. Methodology: Serological investigation was carried out on 219 cattle from 44 herds and 137 camels from 11 herds in contact with the selected cattle herds in Boranara zone and 348 camels from 41 herds in Shinille zone. The sera samples were tested using a competitive enzyme lnked immunosorbent assay (c-ELISA) to detect antibodies against p80 protein of BVDV. In addition, all of the cattle sera were tested using antigen detection ELISA for identification of persistent infection. Results: Among the 219 cattle tested, 177 (80.82%; 95% CI: 74.97-85.81) were found to be positive for antibodies against BVDV in Moyale district, Borena Zone. The prevalence varied among different age groups and parity. The highest prevalence was observed in cattle aged 8 years and older (84.0%; 95% CI: 69.6-98.4) and in primiparous cattle (85.5%; 95% CI: 76.2-94.8). Two of the 219 cattle tested (0.05%; 95% CI: 0.02-0.08) were found to be positive with antigen detection ELISA. In addition, out of a total of 137 camels tested, two (1.46%; 95% CI: 0.18-5.17) were found to be positive in this district. Among the 348 camels tested, eight (2.29%; 95% CI: 0.99-4.485) were found to be positive for antibodies against BVDV. In conclusion, this study revealed a high prevalence of infection in Borana cattle. In addition, it recorded the occurrence of infection with BVDV in camel herds. None of the camels tested positive for the antigen of BVDV using antigen ELISA.