Identification ofantibiotic resistance genes inEscherichia coli from subclinical mastitis milk indairy cows and goats, East Java Province.

Abstract

Antibiotics are still used totreat mastitis indairy cows inIndonesia. This study aimed toanalyse antibiotic resistance genes inEscherichia coli (E.coli) from subclinical mastitis milk inEast Java Province, Indonesia. Thesamples consisted ofsubclinical mastitis milk from cows and goats. Atotal of592-quarter cow's milk and 71goat's milk samples from both halves ofthe udder were collected from 67farms inLumajang, Banyuwangi, Malang, Sidoarjo, Jember, Pasuruan, Probolinggo, and Mojokerto. Subclinical mastitis samples were screened using the California mastitis test (CMT). E.coli was identified byphenotypic and genotypic methods. E.coli wasconfirmed with aprimer specific tothe polymerase chain reaction (PCR) technique. Gene resistance ofE.coli was tested using the multiplex-PCR (mPCR) technique with primers encoding the genes temoneira enzyme (TEM), oxacillinase (OXA), sulfhydryl variable (SHV), and cefotaximase-munich IV (CTX-M IV). These genes were chosen because mastitis treatment generally uses oxacilline and β-lactam antibiotics. All data obtained were analysed descriptively. Theresults show that six isolates ofE.coli (46.15%) carried asingle resistance gene (TEM orSHV) and two isolates (33.33%) were confirmed asmultiple drug-resistant organisms (MDROs) (TEM and SHV). Theresistance genes were found insamples originating from Blitar, Banyuwangi, Lumajang, and Pasuruan Regencies. This research implies that antibiotic-resistance genes found inE.coli oncertain farms are dangerous and may allow gene transmission toother bacteria that make treatment for mastitis orother bacterial infections ineffective.