Shahid Maryam, Hussain Riaz, Nawaz Zeeshan, Aslam Bilal, Ahmad Muhammad Zishan, Siddique Abu Baker, Ahsan Hira, Fatima Aiman, Khan Iahtasham, Mustafa Bilal, Iqbal Rashid, Al Syaad Khalid M, Shami Ashwag
Institute of Microbiology, Government College University, Faisalabad 38040, Pakistan.
Department of Pathology, Faculty of Veterinary and Animal Sciences, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan.
ACS Omega. 2023 Oct 2;8(41):38111-38117. doi: 10.1021/acsomega.3c04206. eCollection 2023 Oct 17.
The occurrence of -induced subclinical mastitis holds significant implications for public health. This specific microorganism possesses a wide array of pathogenic factors that enable it to adhere to, colonize, invade, and infect the host. The objective of the current study was to assess the prevalence of , determine antimicrobial resistance patterns, and identify virulence genes of methicillin-resistant (MRSA) strains responsible for subclinical mastitis in bovines. A total of 249 milk samples were collected from various farms in the district of Faisalabad. The presence of subclinical mastitis was assessed by using the California mastitis test. Positive milk samples ( = 100) were then subjected to standard microbiological techniques for isolation and identification of . Antibiogram analysis was conducted by using the disc diffusion method to assess antimicrobial resistance. For the molecular detection of and its virulence genes, the polymerase chain reaction (PCR) was performed with species-specific primers. The overall prevalence of was found to be 40% (40/100), which was confirmed through molecular detection of the gene in 40/40 (100%) of samples using PCR. Antimicrobial susceptibility tests indicated the highest susceptibility to vancomycin, sulfamethoxazole/trimethoprim, erythromycin, gentamicin, ciprofloxacin, and chloramphenicol, while the highest resistance rate was observed against tetracycline. Additionally, 30% of samples (12/40) tested positive for methicillin resistance. PCR analysis revealed that 100% of MRSA-tested isolates harbored the and genes. Furthermore, the MRSA isolates showed the presence of , , , , , i, , and genes at rates of 92, 75, 67, 42, 42, 75, 8, and 25%, respectively. These findings underscore the need for stricter aseptic control in dairy farms to prevent disease transmission between animals and ensure the production of safe and uncontaminated food for human consumption.
[某种微生物]诱导的亚临床乳腺炎的发生对公共卫生具有重大影响。这种特定的微生物拥有多种致病因素，使其能够附着、定殖、侵入并感染宿主。本研究的目的是评估[某种微生物]的流行率，确定其抗菌耐药模式，并鉴定导致牛亚临床乳腺炎的耐甲氧西林[某种微生物]（MRSA）菌株的毒力基因。从费萨拉巴德地区的各个农场共采集了249份牛奶样本。使用加利福尼亚乳腺炎检测法评估亚临床乳腺炎的存在情况。然后，对100份阳性牛奶样本采用标准微生物技术进行[某种微生物]的分离和鉴定。采用纸片扩散法进行抗菌谱分析，以评估抗菌耐药性。为了对[某种微生物]及其毒力基因进行分子检测，使用物种特异性引物进行聚合酶链反应（PCR）。[某种微生物]的总体流行率为40%（40/100），通过PCR对40/40（100%）的样本进行[某种微生物]基因的分子检测得到了证实。抗菌药敏试验表明，对万古霉素、磺胺甲恶唑/甲氧苄啶、红霉素、庆大霉素、环丙沙星和氯霉素的敏感性最高，而对四环素的耐药率最高。此外，30%的样本（12/40）对甲氧西林耐药检测呈阳性。PCR分析显示，100%检测的MRSA分离株携带[某些基因]。此外，MRSA分离株中[某些基因]的存在率分别为92%、75%、67%、42%、42%、75%、8%和25%。这些发现强调了奶牛场需要更严格的无菌控制，以防止动物之间的疾病传播，并确保生产出供人类食用的安全无污染食品。
