Investigation of the antibiotic resistance and biofilm formation of Staphylococcus aureus strains isolated from gangrenous mastitis of ewes

Abstract

In this study, Staphylococcus aureus strains (n = 110) isolated from seven ewe flocks in Sanliurfa, Turkey were screened for antibiotic resistance and biofilmforming ability as well as for genes associated with antibiotic resistance and biofilm-forming ability. All isolates were found to be susceptible to oxacillin, gentamicin, clindamycin, cefoxitin, tetracycline, vancomycin, amoxicillin-clavulanic acid, ciprofloxacin and sulphamethoxazole-trimethoprim. The percent proportions of strains resistant to penicillin G, ampicillin and erythromycin were 27.2% (n = 30), 25.4% (n = 28) and 6.3% (n = 7), respectively. Regarding the antibiotic resistance genes, 32 (29%) isolates carried the blaZ and 8 (7.2%) the ermC gene. Other resistance genes were not detected in the isolates. All isolates showed biofilm-forming ability on Congo red agar (CRA), while 108 (98.18%) and 101 (91.81%) of them were identified as biofilm producers by the use of standard tube (ST) and microplate (MP) methods, respectively. All isolates carried the icaA and icaD genes but none of them harboured the bap gene. The results demonstrated that S. aureus isolates from gangrenous mastitis were mainly resistant to penicillins (which are susceptible to the staphylococcal beta-lactamase enzyme), and less frequently to erythromycin. Furthermore, all of the S. aureus isolates produced biofilm which was considered a potential virulence factor in the pathogenesis of staphylococcal mastitis.

Clonal profile, virulence and resistance of Staphylococcus aureus isolated from sheep milk

“…, 2001 ). The present results differ from those reported by Tel et al (2012) who analyzed 110 S. aureus strains isolated from cases of sheep clinical mastitis. The isolates did not carry the bap gene, but were positive for the icaA and icaD genes.…”

Phenotypic and Molecular Detection of Biofilm Formation in Staphylococcus aureus Isolated from Different Sources in Algeria

“…The presented data of the DNA microarray analysis revealed that all S. aureus isolates harbored icaACD genes regardless of their origin. These results were in agreement with several findings made in human infections [46], human nasal samples [47], sheep mastitis [48], and isolates from food matrices [6].…”

Antibiotic Resistance Patterns and Virulence Determinants of Different SCCmec and Pulsotypes of Staphylococcus Aureus Isolated from a Major Hospital in Ilam, Iran

“…Several studies have been conducted worldwide on toxic genes of MRSA from various dimensions. In similar clinical studies, the frequency of sea gene of MRSA was 58.8% in Gorgan-Iran, 74.4% in Tehran-Iran, 33% in China, and 12% in Germany, while the frequency of sea gene in MRSA isolates from various specimens obtained in this study was 25% which is similar to that of the study conducted in Korea [ 10 , 23 - 26 ]. Moreover, the frequency of sub gene has been investigated in many studies.…”