Department of Farm Animals, Vetsuisse Faculty University of Zurich, Switzerland.
Institute for Food Safety and Hygiene, Vetsuisse Faculty University of Zurich, Switzerland.
Schweiz Arch Tierheilkd. 2014 Nov;156(11):539-42. doi: 10.1024/0036-7281/a000644.
In this report, we describe two cases of bovine toxic mastitis associated with S. aureus and we provide DNA microarray based characterization data of the strain causing the disease. Both cows had recently calved and suffered from anorexia, pyrexia, and an elevated heart rate. In both animals, at least one mammary gland was swollen, hardened, sensitive to touch, and produced brownish or bloody secretions. The clinical state of the animals deteriorated quickly and both cows had to be euthanized within 48 hours after presentation. The S. aureus strain, which was isolated from the mastitis milk of both cows, was assigned to spa type t267, agr type I, capsule type 5 and CC97, a clonal complex recently identified as the evolutionary origin of two emerging clones of human epidemic community-associated methicillin-resistant S. aureus. The strain did not harbour any genes conferring resistance to antimicrobial agents and we did not detect any genes coding for enterotoxins, toxic shock syndrome toxin, or exfoliative toxins. Taking into consideration that twin cows were affected by this rare disease, we suggest that host factors may play a crucial role in toxic mastitis associated with S. aureus.
在本报告中，我们描述了两例与金黄色葡萄球菌相关的牛中毒性乳腺炎病例，并提供了导致该疾病的菌株基于DNA微阵列的特征数据。两头奶牛均为近期产犊，出现厌食、发热和心率加快症状。在这两头动物中，至少有一个乳腺肿胀、变硬、触痛，并产生褐色或血性分泌物。动物的临床状态迅速恶化，两头奶牛在就诊后48小时内均不得不实施安乐死。从两头奶牛的乳腺炎乳汁中分离出的金黄色葡萄球菌菌株被归类为spa型t267、agr型I、荚膜型5和CC97，CC97是一个克隆复合体，最近被确定为两种新出现的社区获得性耐甲氧西林金黄色葡萄球菌人类流行克隆的进化起源。该菌株未携带任何赋予对抗菌剂耐药性的基因，我们也未检测到任何编码肠毒素、中毒性休克综合征毒素或剥脱毒素的基因。考虑到双胞胎奶牛受到这种罕见疾病的影响，我们认为宿主因素可能在与金黄色葡萄球菌相关的中毒性乳腺炎中起关键作用。
