Caprine paratuberculosis in farm and farmer's goat herds: An assessment of prevalence in target tissues, comparison of culture, PCR and indigenous elisa kit and genotypes of Mycobacterium avium subspecies paratuberculosis

Prevalence of Mycobacterium avium subspecies paratuberculosis on the basis of multiple tests screening by tissue culture, tissue PCR and ELISA kit was 51.7, 37.9 and 46.5% respectively, in the farm and farmer's goatherds in North India. Cumulatively in three tests, 68.9% goats were found positive for MAP infection. In farm goats, ‘true prevalence’ of MAP based on culture and PCR was 54.2% while in farmer's herds 73.9% goats were positive. There was substantial agreement between PCR and ELISA kit with tissue culture. Sensitivity and specificity of ELISA kit was 66.6 and 75.0% and 68.1 and 66.6% with tissue culture and PCR, respectively. Primary colonies were characterized as MAP using IS900 PCR and were further typed as ‘Bison type’ using IS1311 PCR-REA. The high prevalence of MAP in farm and farmer's goatherds may be attributed to lack of priority, expertise and indigenous diagnostic kits.