Potential for genetic control of bovine tuberculosis in Africa

Research suggests that it is likely that a group of genes act together to confer resistance to bovine tuberculosis (bTB). The findings, published in Frontiers in Genetics, will support future research, which could help farmers in Africa select and breed cattle that are more likely to be resistant to this disease in the future.

The study, led by scientists from the Centre of Tropical Livestock Genetics and Health (CTLGH) and the Roslin Institute, also suggests that, contrary to results of previous studies, resistance to bTB is not likely to be linked to a specific breed.

Researchers studied and compared the DNA of 212 cattle in Cameroon. Lymph nodes from the necks of these animals were also sampled and 153 animals were found to be positive for Mycobacterium bovis.

Analysis of the material revealed that some of these animals’ genetic makeup conferred a higher level of resistance against bTB. Researchers also found that, although there were clusters of animals that differed in their resistance to bTB, there were no apparent differences between breeds.

The prevalence of bTB is rising in Cameroon and, with no effective vaccine or treatment, breeding for resistance for bTB may help to control the disease.

This approach has already been implemented in other countries including the UK, where the dairy industry recently introduced a genetic evaluation index that enables farmers and breeders to select Holstein dairy bulls with greater bTB resistance.

Article: Callaby, R., Kelly, R., Mazeri, S., Egbe, F., Benedictus, L., Clark, E., Doeschl-Wilson, A., Bronsvoort, B., Salavati, M., Muwonge, A. (2020). Genetic Diversity of Cameroon Cattle and a Putative Genomic Map for Resistance to Bovine Tuberculosis. Frontiers in Genetics 11:550215, doi: 10.3389/fgene.2020.550215

[SOURCE: The Roslin Institute]