Microarray-based detection of resistance genes in coagulase-negative staphylococci isolated from cattle and buffalo with mastitis in Egypt

AbstractThe present study aimed to provide a detailed characterization of coagulase-negative staphylococci (CoNS) isolated from cows and buffaloes with mastitis. The study included seventy-five CoNS isolates (60 came from cattle and 15 from buffaloes) originating from 68 individual quarters of 67 dairy cows (53 cattle and 14 buffaloes). The animals belonged to five different small holding dairy herds (n = 140 cows) that show clinical or subclinical mastitis. CoNS isolates were phenotypically characterized using MALDI-TOF-MS and were further genotypically characterized by microarray-based assays. Furthermore, the antimicrobial susceptibility of CoNS strains which carried themecA gene was examined by broth microdilution. The occurrence of CoNS in the respective five herds was 10.5%, 14.7%, 14.8%, 12.8%, and 9.9%, with an average of 12.4%. Six different CoNS species were identified:S. sciuri (n = 37; 30 from cattle and 7 from buffaloes),S. chromogenes (n = 14; 8 from cattle and 6 from buffaloes),S. haemolyticus (n = 10; nine from cattle and one buffalo),S. xylosus (n = 10; nine from cattle and one buffalo),S. hyicus (n = 2),S. warneri (n = 1), and unidentified CoNS (n = 1). Twenty percent (20%) of CoNS isolates (17.3% of cattle origin) carried at least one antimicrobial resistance gene, while 4% of the isolate including two isolates ofS. haemolyticus and oneS. warneri of cattle origin carried themecA gene and were phenotypically identified as meth...
Source: Tropical Animal Health and Production - Category: Veterinary Research Source Type: research