Clinical Manifestation and Antimicrobial Resistance Profile of Staphylococcal Mastitis in Sheep

AbstractThe study aimed to report the clinical manifestation, identification, characterization and antimicrobial resistance pattern of Staphylococcus aureus isolated from five mastitis-infected ewes. Mammary secretions were collected and inoculated on nutrient agar. Four isolates of Staphylococcus spp were identified. They were further confirmed by two specific primers which revealed 756 bp amplicon of 16S gene and 270 bp amplicon for thermonuclease gene. These four isolates were further amplified using 16S universal gene primers and compared with NCBI database which confirmed S. aureus. Antimicrobial susceptibility test revealed that these isolates were 75 to 100% sensitive to amikacin, amoxyclav, cefepime, ceftazidime and ceftriaxone and 75 to 100% resistant to bacitracin, cloxacillin, doxycycline, erythromycin, penicillin-G, streptomycin and vancomycin while intermediately sensitive to ampicillin, cefixime, chloramphenicol, chlortetracycline, ciprofloxacin, enrofloxacin, gentamicin, imipenem, kanamycin, methicillin nitrofurantoin, norfloxacin, novobiocin, ofloxacin, polymyxin-B and tetracycline. It was inferred that the isolation of S. aureus as the primary pathogen and its multidrug resistance, particularly against commonly used antibiotics, underscore the need for alternative strategies to manage mastitis effectively.