CLINICAL EVALUATION OF ENROFLOXACIN (BAYTRIL® 5% INJECTABLE SOLUTION, BAYER, ITALY) AGAINST STAPHYLOCOCCUS AUREUS CLINICAL MASTITIS IN SHEEP

Mastitis in ewes has been reported to occur in all the major sheep-breeding countries. The disease is economically important for both sheep and dairy farmers, because of premature culling of ewes and the reduced performance of lambs that nurse from mastitis ewes. The objective of this research were to evaluate the potential role of commercially available enrofloxacin (Baytril®, Bayer, Italy) in controlling the severity of the clinical signs, to improve cure rates against Staphylococcus aureus and to minimize the effects of the disease on the mammary gland.. These studies were conducted in commercial dairy herds where there was ongoing intensive monitoring of subclinical mastitis by Somatic Cell Count (SCC) and bacteriology. From these herds, 2 different groups namely Group A (n=34 animals) and Group B (n=39 animals) were selected and treated with enrofloxacin (Baytril® 5% injectable solution) 2.5mg/kg/bw and 5mg/kg/bw, respectively for three consecutive days (2 dose per day). The efficiency of the enrofloxacin in curing the S. aureus-induced clinical mastitis were monitored with SCC, rectal temperature, local mammary reaction and systemic reaction from the day 1 (D1) to 14th day (D14) of post treatment. The presence or absence of S. aureus in the sheep was confirmed by bacteriological examination and followed by PCR with specific primer, SA nuc, before and after the treatment. The percentage of bacteriological cure was 39% in Group A and the 82% in Group B. The SCC reduction from D1 to D14 was statistically significant (P<0.001) for both group and also between the groups. The mean rectal temperature also decreased significantly (P<0.001) from D1 to D14 in both groups. The local mammary reaction and systemic reaction were decreased significantly in both treated groups. In conclusion, both enrofloxacin concentration shows good response in reducing clinical signs of mastitis like reduction in SCC, rectal temperature, better attitude and bacteriological cure, but the 5mg/kg/bw concentration used in Group B shows best results when compared with 2.5mg/kg/bw concentration of Group A. The present study provides the evidence that Baytril® 5% injectable solution could helps in controlling the S. aureus-induced clinical mastitis in sheep.