Assessment of Ovine Johne’s disease in the Mandya sheep breed in South India using multiple diagnostic tests and bio-typing of Mycobacterium avium subspecies paratuberculosis infection

Johne’s disease is major infectious disease of domestic livestock in India. Despite low per animal productivity, the country is yet to initiate plan for the survey and control of disease at National scale. A total of 81 clinical samples from Mandya breed of sheep were collected from an organised farm (Livestock Research and Information Centre, Nagmangala) and farmer’s flocks suspected for Johne’s disease on the basis of clinical symptoms (weakness, emaciation, diarrhea and alopecia). Only 10.0% samples from two farms were screened for bio-load of Mycobacterium avium subspecies paratuberculosis (MAP) using multiple tests (microscopy, indigenous ELISA, IS900 PCR and culture). Results showed that 100.0% samples were positive for MAP infection both in microscopy and “Indigenous ELISA”. IS1311 PCR-REA bio-typed 60.0% (feces) and 100.0% (blood and tissue) isolates as “Indian Bison Type”. Typing investigated for the first time that biotype was of Indian origin and present in sheep flocks of South India having wide geographical distribution and broad host range. Study reported high bio-load of MAP in Mandya breed of sheep in Nagamangala, Mandya district and Bilagi taluk of Bagalkot district in South India. Being Johne’s disease a spectral disease, multiple tests were useful for the screening of MAP infection in sheep farms. Study emphasised the need for initiation of short and long term control programs to reduce production losses and sharing of MAP strains by other domestic livestock species and prevent contamination of human food chain and reduce risk to human population