Host genetic resistance to mycobacterial infections in bovines
Sushil Kumar, Anuj Chauhan, Amit Baranwal, Arvind Sonwane, Subodh Kumar and Ran Vir Singh
Bovine Tuberculosis and Paratuberculosis of mycobacterial etiology cause severe economic losses to dairy sector and also carry with them the associated risk of public health burden. In absence of cost effective treatment regimens or efficient vaccines for these mycobacterial infections, it is often very difficult to control/manage these at the dairy farms. Control is primarily restricted to culling of cattle that react positively to the single intradermal comparative cervical tuberculin test. Further, reservoirs of TB in wildlife populations have been linked to the persistence or increase of the incidence of bovine TB in some countries. Breeding for increased host resistance to infection is alternative or complementary strategy as changes are permanent. Genetic variation in susceptibility to tuberculosis has been observed in cattle. The present review highlights the underlying host genetic variation in resistance/susceptibility to mycobacterial infections and results of several genetic association studies carried out across the world.