Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, The Netherlands.
J Dairy Sci. 2012 Nov;95(11):6477-82. doi: 10.3168/jds.2012-5548. Epub 2012 Aug 29.
To establish environmental contamination in and around a dairy barn, cows shedding Mycobacterium avium ssp. paratuberculosis (MAP) were housed in a freestall barn. Fecal samples were collected 15 times at 3-wk intervals, and samples of all animals were cultured by using the Trek Diagnostic Systems culture system (Cleveland, OH) to quantify levels of MAP shedding. In parallel, air and floor dust samples were collected inside and outside the experimental farm and analyzed by IS900 real-time PCR for the presence of MAP DNA. Inside the barn, MAP was detected with equal frequency in samples directly contaminated with feces compared with air dust samples above animal level and in dust samples of the corridor. Dust samples collected within the barn were positive more frequently than outside samples, with exception of the outside sample from the farmer's doormat. The risk of MAP exposure was distributed evenly within the dairy barn. Additionally, footwear should be considered as a high-risk fomite for dispersion of dust-related MAP outside the barn. Prevention of MAP exposure in youngstock may require housing of youngstock in separate barns as an additional management measure.
为了确定奶牛场及其周边环境中的污染情况，患有分枝杆菌副结核亚种（MAP）的奶牛被安置在一个自由放养牛舍中。每隔 3 周，共采集了 15 次粪便样本，并使用 Trek 诊断系统培养物（俄亥俄州克利夫兰）对所有动物的样本进行培养，以定量检测 MAP 的脱落水平。同时，在实验农场内外采集了空气和地板灰尘样本，并通过 IS900 实时 PCR 分析 MAP DNA 的存在情况。在牛舍内，直接受粪便污染的样本与动物上方的空气灰尘样本以及走廊的灰尘样本中 MAP 的检出频率相同。牛舍内采集的灰尘样本比牛舍外的样本更频繁呈阳性，除了来自农民门口垫的外部样本。MAP 暴露的风险在奶牛场内部均匀分布。此外，应将鞋类视为牛舍外灰尘传播相关 MAP 的高风险传播媒介。防止幼畜接触 MAP 可能需要将幼畜安置在单独的牛舍中作为额外的管理措施。
