A comprehensive review on subclinical mastitis in dairy animals: Pathogenesis, factors associated, prevalence, economic losses and management strategies

Subclinical mastitis (SCM) particularly affects milk yield, quality and health of lactating animals. It is an apparently invisible problem that silently leads to enormous financial damage to the whole dairy industry. It is evident from previous studies that faulty animal husbandry practices including microbial infections, poor nutrition, unhygienic microenvironment, poor transition management of dairy animals and changing climatic scenarios are major reasons for increased SCM cases. The aim of this manuscript includes summarizing the factors associated with SCM and its effects on various performances of affected animals, detection methods and management strategies (improved nutrition, maintenance of optimum energy balance, genetic selection of mastitis-resistant animals, improved milking practices, hygienic conditions, emerging dry cow therapies, use of bacteriophages, utilization of plant- and animal-derived products and compounds) to curb the SCM cases in dairy animals. However, special emphasis has been made on the management practices that may be helpful in controlling SCM cases in dairy animals. A wide range of practices has been studied towards controlling SCM cases but it may not be denied that SCM is likely to be a continued challenge for the dairy herdsman.