Viral Disease and Epidemiology Research Division, National Institute of Animal Health, 3-1-5 Kannondai, Tsukuba, Ibaraki, Japan.
Viral Disease and Epidemiology Research Division, National Institute of Animal Health, 3-1-5 Kannondai, Tsukuba, Ibaraki, Japan.
Res Vet Sci. 2014 Feb;96(1):47-53. doi: 10.1016/j.rvsc.2013.11.014. Epub 2013 Dec 11.
This cross-sectional study evaluated risk factors associated with farm-level bovine leukemia virus (BLV) seropositivity in 563 dairy and 490 beef farms throughout Japan. Twenty randomly selected cattle on each farm were serologically tested, and farm epidemiologiocal information was obtained through face-to-face interviews. Due to the large number of zero-prevalence dairy and beef farms, data analysis was performed using a zero-inflated negative binomial model, which revealed that the common risk factors associated with higher within-farm seroprevalence were past detection of clinical leukemia and presence of blood-sucking insects. Loose housing on dairy farms and direct contact between calves and adult cattle on beef farms were also identified as risk factors. With regard to farm-level presence of BLV, the presence of purchased cattle was found to be a risk factor in both sectors. Sending heifers to a common ranch was identified as an additional risk factor for dairy farms.
本横断面研究评估了与日本 563 家奶牛场和 490 家肉牛场的牛白血病病毒 (BLV) 血清阳性相关的农场水平的危险因素。对每个农场的 20 头随机选择的牛进行血清学检测，并通过面对面访谈获得农场流行病学信息。由于大量的奶牛场和肉牛场没有零感染，因此使用零膨胀负二项式模型进行数据分析，结果表明，与农场内血清阳性率较高相关的常见危险因素是临床白血病的检测和吸血昆虫的存在。奶牛场的松散式饲养和肉牛场小牛和成年牛之间的直接接触也被确定为危险因素。就 BLV 在农场层面的存在而言，在这两个部门，购买牛只被认为是一个危险因素。将小母牛送到一个共同的牧场被确定为奶牛场的另一个危险因素。
