Progress of Bacteriophage Research and Application in the Treatment of Bovine Mastitis: A Review

Bovine mastitis, caused by both contagious and environmental pathogens, represents a major infectious disease burden in the global dairy industry. Antibiotics remain the primary treatment option, but their effectiveness is limited by the blood–milk barrier, drug residues, and the growing threat of multidrug-resistant bacteria. Among the various alternatives, phage therapy has drawn particular attention due to its specificity, ability to disrupt biofilms, low impact on commensal flora, and self-replication at infection sites. In this review, we summarize recent advances in the isolation of lytic phages targeting major mastitis-causing pathogens, their bactericidal mechanisms, and their performance in vitro and in vivo. We also discuss key obstacles to clinical translation including formulation stability, narrow host range, and safety concerns. Moreover, the potential strategies to overcome these issues are explored. This review provides a useful reference for research on phage therapy against bovine mastitis.