Paratuberculosis or Johne’s disease is a chronic debilitating disease of ruminants caused by Mycobacterium avium paratuberculosis. In dairy cows, paratuberculosis has been associated with production losses such as decreased milk yield, pre-mature culling, reduced carcass value etc. A possible mode of transmission for the ruminant pathogen Mycobacterium avium subsp. Paratuberculosis (MAP) from cattle to humans is via milk and dairy products. Although, MAP has been suggested as the causative agent of Crohn's disease and its presence in consumers' milk might be of concern. During the active stage of infection and prior to the onset of clinical disease, animals generally develop antibodies to MAP antigens. Uninfected animals lack specific antibodies to MAP. In this study a total of 128 milk samples from cattle and buffaloes (irrespective of shedding of acid fast bacilli in the faeces) were screened for the presence of antibodies against MAP. A commercially available in vitro diagnostic kit for detection of antibodies against MAP was used. Seven out of 128 milk samples (5.46%) were positive by ELISA. The percent positivity of > 15% was considered as positive sample. The percent positivity of positive control was considered as 100%. The percent positivity ranged from 20% to 100%. However, none of the milk sample was positive for the presence of MAP by using conventional PCR and real time PCR using Taq Man assay. The presence of MAP specific antibodies in the milk is an indication of prior exposure of the animal to the organism.

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