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The classical MHC class I and class II molecules play key roles in determining the antigenic-specificity of CD8+ and CD4+ T-cell responses-as such characterisation of the repertoire of MHCI and MHCII allelic diversity is fundamental to our ability to understand, and potentially, exploit how genetic diversity influences the outcome of immune responses. Cattle remain one of the most economically livestock species, with particular importance to many small-holder farmers in low-and-middle income countries (LMICs). However, our knowledge of MHC (BoLA) diversity in the indigenous breeds that form the mainstay of cattle populations in many LMICs remains very limited. In this study we develop a MiSeq-based platform to enable the rapid analysis of BoLA-DQA and BoLA-DQB, and combine this with similar platforms to analyse BoLA-I and BoLA-DRB repertoires, to study a large cohort of cattle (~800 animals) representing the 3 major indigenous breeds (Angoni, Barotse, Tonga) in Zambia. The data presented confirms the capacity of this high-throughput and high-resolution approach to provide a full characterisation of the MHCI-MHCII genotypes of cattle for which little previous MHC sequence data has been obtained. The cattle in Zambia were found to express a diverse range of MHCI, MHCII and extended MHCI-MHCII haplotypes. The combined MHCI-MHCII genotyping now possible opens new opportunities to rapidly expand our knowledge of MHC diversity in cattle that could find applications in a related translational disciplines such as vaccine development.

Tick-borne diseases (TBDs) are endemic in Zambia and several other Sub-Saharan countries. They affect livestock production by causing high morbidity and mortality, resulting in increased production losses in terms of live-weight gain, milk production, off-take rates, and draft power. Herein, we applied a facility-based design to assess the proportion and seasonal distribution of theileriosis, babesiosis, anaplasmosis, and heartwater in cattle from selected smallholder farms in Lusaka and Central provinces of Zambia using laboratory records for microscopic examination of haemoparasites. The overall proportions for theileriosis, babesiosis, and anaplasmosis were 33.7% (95% CI: 30.7–38.2%), 8.3% (95% CI: 6.4–10.9%), and 0.5% (95% CI: 0.1–1.4%), respectively. Heartwater was detected in all the six laboratory records reviewed. Lusaka province had the highest proportion of theileriosis at 30.2% (95% CI: 25.5–35.3%), followed by babesiosis, 8.5% (95% CI: 5.8–11.9%), and anaplasmosis, 0.3% (95% CI: 0.01–1.6%). Similarly, Central province had the highest proportion of theileriosis at 39.5% (95% CI: 33.8–45.4%), followed by babesiosis, 8.4% (95% CI: 5.5–12.2%), and anaplasmosis, 0.7% (95% CI: 0.1–2.5%). Among the districts, Rufunsa district had the highest proportion for theileriosis at 70.6% (95% CI: 44.0–89.7%), followed by Kafue, 54.5% (95% CI: 23.4–83.3%), and Shibuyunji, 51.4% (95% CI: 34.0–68.6%). Analysis of seasonal variation revealed no statistical difference between the dry and wet seasons for theileriosis, babesiosis, and anaplasmosis. Furthermore, there was no statistical difference between Central and Lusaka provinces for babesiosis and anaplasmosis except for theileriosis. These data may have implications on farmers’ herd health management strategies with respect to TBDs, and farmers should be sensitized for effective implementation of risk-based disease control.

Background: The occurrence of Major Histocompatibility complex (MHC) alleles associated with resistance to Mastitis, Bovine Leukaemia Virus (BLV), Theileriosis, Foot and Mouth Disease (FMD) and susceptibility Dermatophilosis in African cattle is ill defined. Methods: Here, we used manual annotation to screen for five MHC alleles previously known to be associated with resistance/susceptibility to these diseases from a database of alleles sequenced from 846 cattle in Zambia. Results: Overall, we found 28 (3.3%), 21 (2.6%), 55 (6.5%), and 15 (1.8%) animals with resistance alleles to Mastitis, BLV, Theileriosis, FMD and 39 (4.6%) animals with susceptibility alleles to Dermatophilosis, respectively. Conclusion: This study provides the first evidence of resistance/susceptibility alleles in smallholder cattle in Zambia and the data could aid strategies for breeding cattle with enhanced resistance to disease in endemic countries.

Whilst bovine leukemia virus (BLV) causes considerable economic losses to the dairy industry worldwide, information on its molecular epidemiology and economic impact in beef cattle is limited. Here, blood from 880 animals from Zambia's major cattle-rearing provinces was screened for BLV by nested PCR. Positive pools were sequenced and phylogenetically analyzed. The estimated pooled prevalence was 2.1%. All strains belonged to genotype 1 and formed a distinct phylogenetic cluster. The study suggests circulation of genotype 1 BLV in beef cattle in these regions. This is the first report on molecular detection and characterization of BLV from beef cattle in Africa.

Brucellosis is an infectious zoonosis that has huge economic and public health implications globally. The disease is prevalent in humans, livestock and wildlife in Sub-Saharan Africa. A cross-sectional study was conducted between 6 May 2017 and 31 July 2020 during which 1712 sera from 175 cattle herds in five districts from Southern, Western and Eastern Provinces of Zambia were collected and screened against brucellosis. The Rose Bengal Test (RBT) and competitive Enzyme-linked Immuno Assay (c-ELISA) were used in serial testing for the detection of antibodies against Brucella species. A total of 127 animals from 37 herds tested positive, giving overall individual animal and herd-level seroprevalences of 7.53% (95% CI: 6.28–8.78%) and 21.14% (95% CI: 15.0–27.2%), respectively. Namwala district had the highest herd seroprevalence (33.9%, 95% CI: 21.6–46.1%), while Lundazi did not record any seropositivity. Comparably, Southern Province had the highest individual animal (8.97%, 95% CI: 7–11%) and herd-level (28.5%, 95% CI: 20.3–36.7%) seroprevalences, although this was not statistically significant. Within Southern Province, higher seropositivity was observed in Namwala district (OR: 8.55, CI: 2.66–27.44), among female animals (OR: 2.48, CI: 1.38–4.46) and in those aged 11 years and above (OR: 2.67, CI: 1.34–5.34) as well as in gravid cows (OR: 4.34, CI: 2.08–8.92). Seropositivity was also observed among some animals with hygromas (OR: 6.5, CI: 0.45–94.08) and those with a history of abortion (OR: 1.13, CI: 0.18–7.28) although the findings were not statistically significant. Brucella seroprevalence among traditional cattle in Zambia remains high. Control programs against bovine brucellosis must be introduced to reduce its impact on human health and animal production.

Brucellosis is an infectious zoonosis that has huge economic and public health implications globally. The disease is prevalent in humans, livestock and wildlife in Sub Saharan Africa. A cross-sectional study was conducted between 6th May 2017 and 31st July 2020 during which 1712 sera from 177 cattle herds in Southern, Western and Eastern provinces of Zambia was collected and screened against brucellosis. Rose Bengal Test and c-ELISA were used in serial testing for detection of antibodies against Brucella species. Results: A total of 127 animals and 37 herds tested positive, giving an overall individual and herd seroprevalence of 7.42% (CI: 0.61-0.86) and 20.9% respectively. Namwala district recorded the highest seroprevalence (12.2%) while Lundazi had the lowest (0%). A higher seropositivity was observed among female animals (8.5%), those aged between 11 and 17 years (14.1%) and pregnant cows (13.8%). Conclusions: Brucella seroprevalence among traditional cattle in Zambia remains high. It is vital that control programmes against bovine brucellosis are introduced in order to reduce its zoonotic impact on human health and increase animal production.