Bandyopadhyay Samiran, Samanta Indranil, Bhattacharyya Debaraj, Nanda Pramod Kumar, Kar Debasish, Chowdhury Jayanta, Dandapat Premanshu, Das Arun Kumar, Batul Nayan, Mondal Bimalendu, Dutta Tapan Kumar, Das Gunjan, Das Bikash Chandra, Naskar Syamal, Bandyopadhyay Uttam Kumar, Das Suresh Chandra, Bandyopadhyay Subhasish
a Indian Veterinary Research Institute , Eastern Regional Station , 37 Belgachia Road, Kolkata - 700 037 , India.
Vet Q. 2015 Mar;35(1):56-61. doi: 10.1080/01652176.2014.984365. Epub 2014 Dec 2.
Emergence of antimicrobial resistance among bovine mastitis pathogens is the major cause of frequent therapeutic failure and a cause of concern for veterinary practitioners. This study describes intra-mammary infection of methicillin-resistant Staphylococcus epidermidis (MRSE), methicillin-resistant Staphylococcus aureus (MRSA) and extended spectrum β-lactamase (ESBL) producing Escherichia coli in two Holstein Friesian crossbred cows with subclinical mastitis and one non-descript cow with clinical mastitis in two different districts of West Bengal, India. In total, three MRSE, one MRSA and three ESBL producing E. coli were isolated from these cases. Both the crossbreds were detected with MRSE (HFSE1 and HFSE2) and ESBL producing E. coli (HFEC1 and HFEC2), whereas, simultaneous infection of three pathogens viz. MRSA (NDSA1), MRSE (NDSE1) and ESBL producing E. coli (NDEC1) was found in the non-descript cow. The methicillin-resistant isolates possessed mecA gene and exhibited resistance to various antibiotics such as amikacin, tetracycline and glycopeptides. The ESBL producers were positive for blaCTX-M and blaTEM genes; in addition, HFEC1 and HFEC2 were positive for blaSHV and possessed the genes for class I integron (int1), sulphonamide resistance (sul1), quinolone resistance (qnrS) and other virulence factors (papC, iucD and ESTA1). All the ESBL producers exhibited resistance to a variety of antibiotics tested including third- and fourth-generation cephalosporins and were also intermediately resistant to carbapenems. This is the first ever report on simultaneous occurrence of MRSE, MRSA and ESBL producing E. coli in bovine mastitis indicating a major concern for dairy industry and public health as well.
牛乳腺炎病原体中抗菌药物耐药性的出现是治疗频繁失败的主要原因，也是兽医从业者关注的问题。本研究描述了在印度西孟加拉邦两个不同地区的两头荷斯坦弗里生杂交亚临床乳腺炎奶牛和一头非纯种临床乳腺炎奶牛中耐甲氧西林表皮葡萄球菌（MRSE）、耐甲氧西林金黄色葡萄球菌（MRSA）和产超广谱β-内酰胺酶（ESBL）大肠杆菌的乳房内感染情况。从这些病例中总共分离出3株MRSE、1株MRSA和3株产ESBL大肠杆菌。两头杂交奶牛检测出感染了MRSE（HFSE1和HFSE2）和产ESBL大肠杆菌（HFEC1和HFEC2），而在非纯种奶牛中发现了三种病原体的同时感染，即MRSA（NDSA1）、MRSE（NDSE1）和产ESBL大肠杆菌（NDEC1）。耐甲氧西林分离株携带mecA基因，并对阿米卡星、四环素和糖肽等多种抗生素表现出耐药性。产ESBL菌株blaCTX-M和blaTEM基因呈阳性；此外，HFEC1和HFEC2的blaSHV呈阳性，并拥有I类整合子（int1）、磺胺耐药性（sul1）、喹诺酮耐药性（qnrS）和其他毒力因子（papC、iucD和ESTA1）的基因。所有产ESBL菌株对包括第三代和第四代头孢菌素在内的多种测试抗生素均表现出耐药性，并且对碳青霉烯类药物也呈中度耐药。这是首次关于牛乳腺炎中同时出现MRSE、MRSA和产ESBL大肠杆菌的报告，这对乳制品行业和公共卫生也构成了重大担忧。
