Sero-Prevalence of Paratuberculosis (Johne's Disease) in Cattle Population of South-Western Bangalore Using ELISA Kit

Abstract

Johne's disease or paratuberculosis is a chronic mycobacterial infection that affects cattle, sheep, goats and other ruminants , adversely, leading to huge economic losses throughout the world. The estimation of sero-prevalence of this disease in the cattle population of southwestern Bangalore, Karnataka, using an immunological assay and statistical analyses, was the objective of this study. One of the diagnostic tools used to detect an antigen or an antibody in animal serum or milk is the Enzyme Linked Immuno-Sorbent Assay, which has been widely used in the research and diagnosis of animal and human diseases as its accuracy is of nanogram-picogram/milliltre level. In the present study, indirect-ELISA was used to diagnose and estimate the sero-prevalence of paratuberculosis in cattle showing diarrhoea and/or anaemia, at 5 local dairy farms in southwest Bangalore, India. Out of 350 bovine serum samples, 53 (15.14%) were positive, 55 milk samples out of 300 were found positive (18.33%) for antibody against Johne's disease by indirect ELISA. The positive samples were then confirmed by direct smear examination of dung by Ziehl-Neelsen staining. Statistical analyses were carried out to indicate the seroprevalence ofJohnès disease in the cattle population of this region to be 15 ± 10%, taking a confidence interval of 95%. The results emphasize the need to prevent the further spread of infection to other susceptible animals and humans as the causative organism, Mycobacterium avium subsp. paratuber-culosis is implicated in Crohn`s disease, an irritable bowel syndrome in humans.