M-team and Mastitis and Milk Quality Research Unit, Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Milk Control Centre Flanders, Lier, Belgium.
Vet Microbiol. 2014 Aug 27;172(3-4):466-74. doi: 10.1016/j.vetmic.2014.06.011. Epub 2014 Jun 21.
Coagulase-negative staphylococci (CNS) are abundantly present in the dairy farm environment and on bovine skin and mucosae. They are also the most prevalent bacteria causing bovine intramammary infections (IMI). Reservoirs and transmission routes of CNS are not yet fully unraveled. The objectives of this study were to explore the distribution of CNS in parlor-related extramammary niches and to compare it to the distributions of CNS causing IMI in those herds. Niches that were targeted in this study were cows' teat apices, milking machine unit liners, and milker's skin or gloves. Each of the three herds had its own CNS microbiota in those niches. The most prevalent species in the parlor-related extramammary niches were Staphylococcus cohnii, S. fleurettii, and S. equorum in the first, second, and third herd, respectively, whereas S. haemolyticus and S. sciuri were found in all herds. S. cohnii and S. fleurettii, as well as S. haemolyticus, which was present in each herd, were also frequently found in milk samples. By contrast, S. chromogenes, S. simulans, and S. xylosus favored the mammary gland, whereas S. equorum was more common in the parlor-associated niches. Within each herd, species distribution was similar between teat apices and milking machine unit liners. In conclusion, some of the extramammary niches related to the milking process might act as infection sources for IMI-causing CNS. This study provides further evidence that the group of CNS species is comprised of environmental, opportunistic and host-adapted species which differ in ecology.
凝固酶阴性葡萄球菌（CNS）在奶牛场环境和牛的皮肤及黏膜中大量存在，也是引起奶牛乳腺炎的最常见细菌。CNS 的传染源和传播途径尚未完全阐明。本研究的目的是探索牛舍相关的非乳腺腔隙中 CNS 的分布情况，并将其与这些牛群中引起乳腺炎的 CNS 分布情况进行比较。本研究的目标腔隙包括奶牛乳头顶端、挤奶机部件衬垫以及挤奶工的皮肤或手套。每个牛群的这些腔隙中都有自己的 CNS 微生物群。在与牛舍相关的非乳腺腔隙中，最常见的物种分别是第一、第二和第三牛群中的凝固酶阴性葡萄球菌、S. fleurettii 和 S. equorum，而 S. haemolyticus 和 S. sciuri 则存在于所有牛群中。在每个牛群中都存在的 S. cohnii 和 S. fleurettii 以及 S. haemolyticus 也经常在奶样中发现。相比之下，S. chromogenes、S. simulans 和 S. xylosus 更喜欢乳腺，而 S. equorum 在与牛舍相关的腔隙中更为常见。在每个牛群中，乳头顶端和挤奶机部件衬垫之间的物种分布相似。综上所述，一些与挤奶过程相关的非乳腺腔隙可能是引起乳腺炎的 CNS 的感染源。本研究进一步证明，CNS 物种组由环境、机会性和宿主适应性的物种组成，这些物种在生态学上存在差异。
