Investigation of mecA, vanA and pvl genes in Staphylococcus aureus strains isolated from bovine mastitis in smallholder dairy farms

Abstract

This study aimed to isolate the Staphylococcus aureus from bovine mastitis, investigate the presence of mecA, vanA and pvl genes in isolated strains and determine the antibiotic resistance of S. aureus strains to some antibiotics commonly used in veterinary field. In the present study, 602 mammary quarter milk samples belong to 170 lactating cows from 40 different smallholder dairy farms located center town and villages of Afyonkarahisar were used. After the CMT scoring, the milk samples were aseptically collected from each mammary quarter. In this study, a total of 23 (3.8%) S. aureus strains were isolated from 602 mammary quarter milk samples by using a commercial identification kit. The presence of mecA, vanA and pvl genes was found in none of the strains. Phenotypic resistances of all S. aureus strains to 12 antibiotics were investigated by using Kirby-Bauer disc diffusion method. The highest resistance rate in strains was against penicillin G (52.2%), followed by oxacillin (21.7%), erythromycin (21.7%) and amoxicillin+clavulanic acid (17.4%). In conclusion, it was noted that S. aureus was not a prevalent pathogen in the etiology of bovine mastitis for the smallholder farms sampled.