Cattle TB detection gets better test
doi:10.1038/nindia.2019.97 Published online 23 July 2019
Researchers have developed a skin test that can detect tuberculosis (TB) in cattle more efficiently than existing techniques1. This test can distinguish infected animals from the ones that have been vaccinated.
Mycobacterium bovis, a close cousin of Mycobacterium tuberculosis, which causes TB in humans, infects a wide variety of animals, including cattle. This bacterium also jumps from animals to humans, accounting for 10 per cent of the total human TB cases globally.
Existing tests are not sensitive and efficient in detecting the bacterium that causes TB in cattle. To devise a better test, an international research team, including a scientist from the Cisgen Biotech Discoveries in Chennai, India, designed a test using a cocktail of small synthetic peptides that can detect the presence of specific antigens, proteins found in M. bovis.
Field tests conducted on 25 infected cattle in Ethiopia confirmed that the new test was superior to the standard test used in an endemic region.
The new test is a less complex version of the synthetic peptide cocktails described in recent studies that have shown promise as an alternative to genetically modified proteins. However, the previously made peptide cocktails consist of large, complex peptides that are too expensive for widespread commercial use.
The researchers say the refined cocktail of synthetic peptides used in the new test may help overcome regulatory restrictions in countries such as India, where use of genetically modified proteins is not allowed.
1. Srinivasan, S. et al. A defined antigen skin test for the diagnosis of bovine tuberculosis. Sci. Adv. 5 (2019) doi: 10.1126/sciadv.aax4899