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Background: Despite the availability of genomic methods for determining the origin and divergence of domestic cattle in East Africa, particularly Ethiopia, knowledge regarding their genetic adaptability and divergence remain limited. To investigate signatures of selection Ethiopian cattle populations were genotyped with an 80K SNP array and European beef cattle breeds were also used for comparison purposes. Results: Across Ethiopian cattle populations, the mean observed and expected heterozygosity were 0.403 and 0.400, respectively. Similarly, for European cattle, observed and expected heterozygosity were 0.25 and 0.26 respectively. PCA and NJ-tree revealed a separation of Ethiopian cattle breeds from European beef breeds. NJ-tree grouped the study cattle according to their breed group with close clustering of Ethiopian cattle populations. The top 1% FST values were considered to delimit genomic regions under positive selection. Some of the candidate genes are involved in biological processes and pathways linked to meat quality attributes determined. Furthermore, some of the candidate genes are associated with tropical adaptation to heat tolerance and resistance to disease. Conclusion: The levels of genetic variation for SNPs on the Bovines GGP-80K assays obtained in this study indicate that these assays have utility for genetic studies in Ethiopian indigenous cattle breeds. The genetic distance of the indigenous Ethiopian breeds from European beef breeds coincides with existing knowledge, that European beef breeds considered under this study are artificially selected and are taurine, while Ethiopian indigenous breeds are naturally selected.

a b s t r a c t Although tuberculosis is endemic in cattle in Ethiopia, little information is available on tuberculosis in dromedaries. Thus, this study was designed to investigate the epidemiology of tuberculosis and its causative agents in dromedaries slaughtered at four representative abattoirs in eastern Ethiopia. A total of 293 dromedaries were examined by detailed post- mortem examination and the prevalence of tuberculosis-compatible lesion (TCL) was 12.3% (36/293), and occurrence of lesion was significantly associated with female dromedaries (95% confidence interval (CI) (0.19-0.97)). Mycobacteria were isolated in 61% (22/36) of the dromedaries with gross lesions. Further characterization of the isolates using PCR showed that 68% (15/22) of the isolates were non-tuberculosis mycobacteria (NTM) while 13.6% (3/22) were Mycobacterium tuberculosis (M. tuberculosis) and 18% (4/22) were not members of the genus Mycobacterium. Spoligotyping of the three M. tuberculosis isolates revealed that one of the three isolates was SIT 21 while the remaining two isolates with octal values of 773357776763671 and 773357777763661 were not reported to the SITVIT database. The isolation of large proportion of NTM from tuberculosis-compatible lesions in dromedary is suggestive of these bacteria being pathogenic to the species, while the isolation of M. tuber- culosis from dromedary carcasses highlights the zoonotic risk represented by consuming the meat. © 2012 Elsevier B.V. All rights reserved.

Species of the genus Cryptosporidium are protozoan parasites (Apicomplexa) that cause gastroenteritis in animals and humans. Of these Cryptosporidium parvum and Cryptosporidium hominis are the major causative agents of human cryptosporidiosis. Whereas infection is self-limiting in the immunocompetent hosts, immunocompromised individuals develop a chronic, life-threatening disease. As specific therapeutic or preventive interventions are not yet available, better understanding of the immune response to the parasite is required. This minireview briefly summarizes the factors involved in the innate and acquired immune response in this pathogen-host interaction with an emphasis on more recent data from mouse models of infection.