The influence of cattle breed on susceptibility to bovine tuberculosis in Ethiopia

Animal Health and Veterinary Laboratories Agency, TB Research Group, New Haw, Addlestone, Surrey KT15 3NB, United Kingdom.
Comparative immunology, microbiology and infectious diseases (Impact Factor: 2.02). 02/2012; 35(3):227-32. DOI: 10.1016/j.cimid.2012.01.003
Source: PubMed


Bovine tuberculosis in domestic livestock such as cattle is an economically important disease with zoonotic potential, particularly in countries with emerging economies. We discuss the findings of recent epidemiological and immunological studies conducted in Ethiopia on host susceptibility differences between native zebu and the exotic Holstein-Friesian cattle that are increasingly part of the Ethiopian National herd, due to the drive to increase milk yields. These findings support the hypothesis that native Zebu cattle are more resistant to bovine tuberculosis. We also summarise the results of experimental infections that support the epidemiological data, and of laboratory experiments that suggest a role for the innate immune response, and in particular interleukin-6, in the outcome of bovine tuberculosis infection.

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Available from: Abraham Aseffa, Jan 13, 2014
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    • "The indigenous cattle and the prevailing extensive rural production systems are unlikely to be able to satisfy the rise in this demand for livestock food products. Therefore, intensification of animal husbandry in developing countries has been sought (Vordermeier et al., 2012). Numerous key factors, combining biological, industrial and political aspects, were involved in these trends, having affected the current genetic status of indigenous cattle breeds, imposing risk on its diversity. "
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    • "On the other hand, the introgressed animals descend, in part, from European cattle, which have not had the same history of selective pressures. It has been found that European breeds are more susceptible than local breeds to some infectious diseases that are prevalent in Africa, such as East Coast Fever [31,32], bovine tuberculosis [33,34], and trypanosomiasis [35,36]. Thus, the European breeds are, in this important respect, less well adapted to the East African environment, and introgressed animals, while more heterozygous due to outbreeding, are also less locally adapted. "
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    • "Besides differences in husbandry, the observed variation in lesion distribution may also indicate genetic differences in TB susceptibility among breeds. European Bos taurus cattle breeds in Ethiopia have been shown to be more susceptible than native Bos indicus cattle [61]. There is also evidence of heritable variation in TB susceptibility within breeds in Irish cattle [62] and so our findings are consistent with the view that host genetic variation influences the outcome of exposure to M. bovis and that knowledge of this variation may have a role in future disease control programmes [63]–[65]. "
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