Bio-contamination estimates of Mycobacterium avium subspecies paratuberculosis in fresh cottage cheese (paneer) sold in rural, semi-urban and peri-urban regions of South Uttar Pradesh using multiple diagnostic tests

Abstract

Paneer (fresh cottage cheese) samples collected from local dairy shops in rural (Farah), peri-urban and urban (Mathura and Agra) regions of South Uttar Pradesh were screened by six tests combinations to estimate the rate of 'bio-contamination' and 'bio-typing' of MAP (paraTB bacilli). Of 55 paneer samples screened, 54.5, 32.7, 54.5, 74.5, 50.9 and 63.6% were positive by microscopy, IS900 PCR, indigenous ELISA kit, Dot-ELISA, Latex Agglutination test and indirect Fluorescent Antibody tests, respectively. Except 2 (3.6%), all the positive samples were detected by minimum two tests. Of the six test combinations used and compared, microscopy (AFB vs iFAT and IS900 PCR were best combinations for the detection of MAP in fresh cottage cheese (paneer) samples. High rate of bio-contamination of paneer sold by the local dairy shops was due to the use of milk supplies contaminated with high bio-load of MAP. Milk supplies were sourced from domestic livestock belonging to local rural areas, where animal health care facilities and knowledge on bio-contamination of MAP were non-existent. Therefore, in order to produce clean milk, free of MAP bacilli it is absolutely essential to control infection in the domestic livestock.