Vol. 7, Issue 11 (2018)

Author(s):
Arthanari Eswaran M, Vadivoo VS, Hariharan T and Sukumar K

Abstract:
The present investigation was undertaken to monitor antimicrobial sensitivity pattern of bacteria causing bovine clinical mastitis from 2015 to 2017 in Tirupur district. Out of 105 mastitis milk samples examined, 85 bacterial isolates were obtained. The isolates were identified according to the cultural, morphological and biochemical characteristics as per standard methods. All the isolates were subjected to antimicrobial sensitivity testing by Kirby-Bauer disc diffusion methods using different antibiotics. The predominant mastitis causing pathogens were Escherichia coli (40%) followed by Staphylococcus aureus, (27%), Klebsiella pneumoinae (20%) and Streptococcus dysgalactiae (13%). The highest and consistent sensitivity was recorded against Enrofloxacin (95.3%) followed by Gentamicin (92.1%) and Ciprofloxacin (89.2%) throughout the study period. The antibiotic resistance was recorded against Streptomycin, Amoxycillin, Penicillin, Oxytetracyclin, Chloramphenicol, Amoxyclav and Ceftriaxone (90.8% to 49.8%). The isolates showed high resistance towards Streptomycin (90.8%), Amoxycillin (81.6%) followed by Penicillin (76%), Oxytetracyclin (60.7%), Chloramphenicol (54.2%) and Amoxyclav (53.2%). The improper selection of antimicrobial drugs and overdose to reduce infection of mammary glands might lead to development of resistant bacteria. The present study showed that routine investigation, in-vitro antimicrobial sensitivity testing and recording of epidemiology of bovine mastitis should be carried out to decide the appropriate antimicrobial drug for successful treatment of mastitis and thereby preventing the development of antimicrobial resistance.