Burns A, Shore A C, Brennan G I, Coleman D C, Egan J, Fanning S, Galligan M C, Gibbons J F, Gutierrez M, Malhotra-Kumar S, Markey B K, Sabirova J S, Wang J, Leonard F C
School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
Microbiology Research Unit, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Ireland; Department of Clinical Microbiology, School of Medicine, Trinity College Dublin, St. James's Hospital, Dublin 8, Ireland.
Vet Microbiol. 2014 Dec 5;174(3-4):504-513. doi: 10.1016/j.vetmic.2014.10.009. Epub 2014 Oct 25.
The emergence of methicillin-resistant Staphylococcus aureus (MRSA) in livestock has refocused attention on S. aureus colonization and transmission in pigs. This study investigated the effect of the S. aureus colonization status of a sow on the colonization status of her piglets, and whether pigs carry the same strain of S. aureus throughout production. Nasal swabs were collected from the piglets of six healthy sows two days after birth and two days before and two days after they were moved into each production stage. The average prevalence of S. aureus colonization varied between 26% and 73%. The odds of being S. aureus positive were almost 12 times higher for piglets born to nasal-positive sows than for those born to nasal-negative sows, and three times higher again for piglets born to sows that were both nasal- and vaginal-positive. Isolates recovered from piglets immediately after birth were indistinguishable from those of the dam as determined by phenotypic and molecular typing, including microarray analysis and optical mapping. All isolates belonged to clonal complex 9 and the majority exhibited a novel spa type, t10449. The findings show that the S. aureus colonization status of the sow influences the colonization status of her piglets in the early production stages but strains carried by pigs change over time. Multiresistant S. aureus was detected, in particular post-weaning. Results suggest that sow status and management practices, including mixing of pigs and antimicrobial usage at weaning, should be considered when implementing control measures for S. aureus on a farm.
家畜中耐甲氧西林金黄色葡萄球菌（MRSA）的出现，使人们重新关注猪体内金黄色葡萄球菌的定植和传播情况。本研究调查了母猪金黄色葡萄球菌定植状态对其仔猪定植状态的影响，以及猪在整个生产过程中是否携带同一菌株的金黄色葡萄球菌。在六头健康母猪的仔猪出生后两天、进入每个生产阶段前两日和进入后两日采集鼻拭子。金黄色葡萄球菌定植的平均患病率在26%至73%之间。鼻腔阳性母猪所生仔猪金黄色葡萄球菌呈阳性的几率几乎是鼻腔阴性母猪所生仔猪的12倍，而鼻腔和阴道均为阳性的母猪所生仔猪的这一几率更是高出3倍。通过包括微阵列分析和光学图谱在内的表型和分子分型方法确定，出生后立即从仔猪身上分离出的菌株与母猪的菌株无法区分。所有分离株均属于克隆复合体9，大多数表现出一种新的spa型，即t10449。研究结果表明，母猪金黄色葡萄球菌定植状态在生产早期会影响其仔猪的定植状态，但猪所携带的菌株会随时间变化。检测到了多重耐药金黄色葡萄球菌，尤其是在断奶后。结果表明，在农场实施金黄色葡萄球菌控制措施时，应考虑母猪状态和管理措施，包括猪的混群和断奶时的抗菌药物使用情况。
