High prevalence of culture-negative intramammary infections and diagnostic limitations of conventional microbiological culture in bovine mastitis of Bareilly region, India

This study evaluated the prevalence, bacteriological profile, and diagnostic limitations associated with conventional culture-based detection of mastitogens in bovine mastitis from Bareilly region of Uttar Pradesh, India. A total of 486 lactating cows comprising 1872 functional quarters were screened using clinical examination, California Mastitis Test (CMT), Somatic Cell Count (SCC), and Total Bacterial Count (TBC). Milk samples from CMT-positive quarters were subjected to microbiological culture, Gram staining, selective media isolation, and biochemical characterization. The prevalence of mastitis was 50.21% at cow level and 20.67% at quarter level. Staphylococci predominated (37.72%), followed by Streptococci (21.19%) and Coliform bacilli (12.66%). Notably, 19.37% of samples showed no growth and 5.68% were contaminated. Approximately 25.06% of samples failed to yield definitive microbiological results. The findings highlight significant diagnostic gaps in routine bacteriological culture and underscore the necessity of integrating molecular diagnostics for accurate detection of intramammary infections.