Comparative efficacy of different treatment regimens against bovine mastitis caused by Staphylococcus aureus

Bovine mastitis is an endemic disease among dairy cattle all over the world and antimicrobial therapy is one of the prime therapeutic and prophylactic tool against mastitis. In the present scenario, the efficacy of antimicrobial chemotherapy is being threatened by the rising tide of antimicrobial resistance. A study was conducted to evaluate the comparative clinico-therapeutic efficacy of three selected antimicrobial protocols among 21 animals with clinical mastitis, from which S. aureus could be isolated. Therapeutic trials were conducted with Inj. Ceftriaxone (10 mg/kg body weight BID) for five days in group I, Inj. Ceftriaxone-sulbactam (6 mg/kg IV BID for five days) in group II and Inj. Sulphadiazine-trimethoprim (15 mg/kg IV BID for five days) in group III. The bacteriological cure was assessed by streaking the milk samples collected 24 h after termination of the treatment on to a bacteriological medium and the clinical cure was assessed by the return to normal colour and consistency of milk and remission of the pathological manifestations in udder. All the treatment groups had exhibited an excellent bacteriological cure rate as evident from the 100 per cent post treatment culture negative samples. The group I exhibited 100 per cent clinical cure whereas, in group II and group II, the clinical cure was 87.5 per cent and 75 per cent respectively. Statistical analysis using Fisher’s exact test revealed that there is no significant difference among the three treatment groups and all the treatment regimens are equally effective