THERAPEUTIC EFFICACY OF BACTERIOPHAGE AND ANTIBIOTICS IN STAPHYLOCOCCAL MASTITIS IN CATTLE

Abstract

Bovine mastitis is one of the most prevalent and economically significant diseases of dairy cattle, causing substantial losses due to reduced milk yield, poor milk quality, increased treatment costs, and milk discards. It is a multifactorial disease caused by a variety of infectious agents, including bacteria, fungi, and algae, along with non-infectious factors. Among these, Staphylococcus spp. are the predominant bacterial pathogens due to their persistence as subclinical infections, poor therapeutic response. Although antibiotics remain the primary line of treatment, their prolonged and indiscriminate use has contributed to the emergence of antimicrobial resistant (AMR) strains, necessitating the exploration of alternative therapeutic approaches. The present study evaluated the comparative therapeutic  efficacy of intramammary bacteriophage with antibiotics therapy.  Twenty four clinical cases of cattle affected with staphylococcal mastitis were randomized into four treatment groups i.e. T1, T2. T3 and T4 for therapeutic trial.  Animals in T1 group animals were treated with antibiotic alone, in T2 group with bacteriophage followed by antibiotic eight hours later, in T3 group antibiotic followed by bacteriophage eight hours later, and T4 with simultaneous therapy antibiotic and bacteriophage. Cefoperazone sodium and a Staphylococcus-specific bacteriophage cocktail were administered intramammarily. Therapeutic response was assessed based on clinical recovery and analyzed using logistic regression. The highest recovery rate was observed in T2 (83.33%; 5/6; OR=0.038), followed by T4 and T3, whereas T1 showed the lowest efficacy. The results indicate that sequential administration of bacteriophage followed by antibiotic is more effective than monotherapy or other combination regimens. This approach offers a promising alternative strategy for the management of staphylococcal mastitis and may help in reducing antimicrobial resistance in dairy cattle.