Risk Factors Associated with Prevalence of Bovine Brucellosis in Milk from Tamil Nadu, India

Abstract

The prevalence of clinical and subclinical mastitis associated with risk factors and their extent of association was studied based on the positivity of 454 mastitis milk samples by polymerase chain reaction (PCR), collected from clinical and subclinical mastitis cows which were brought to the Veterinary College and Research Institute (VC&RI), Namakkal, Tamil Nadu. The prevalence of clinical mastitis was high in cows at 4 th lactation and above (55.8%, OR-3.37), late lactation (65.3%, OR-5.55), of H-F crossbreed (39.0%, OR-1.81), with the previous incidence of mastitis (48.5%), under concrete bedding (30.4%, OR-0.99), without the practice of pre-teat dipping (41.3%, OR-28.0), with post-teat dipping (39.8%, OR-0.06), under hand milking (34.0%) and in the winter season (41.3%, OR-2.50). The prevalence of subclinical mastitis was high in cows at 4 th lactation and above (44.1%, OR-2.99), late lactation (34.6%, OR-2.93), of other breeds (29.7%, OR-1.46), under soil bedding (24.9%, OR-1.60), without practice of pre-teat dipping (31.9%, OR-58.59), with post-teat dipping (28.5%, OR-0.24), under hand milking (23.0%) and in the winter season (34.4%, OR-2.9). The prevalence of clinical and subclinical mastitis was statistically significant in cows between ages of lactation, stages of lactation and seasons, whereas no significant difference could be observed between breeds of cows.