Bartlett Paul C, Sordillo Lorraine M, Byrem Todd M, Norby Bo, Grooms Daniel L, Swenson Cheryl L, Zalucha Jessica, Erskine Ronald J
Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.
J Am Vet Med Assoc. 2014 Apr 15;244(8):914-22. doi: 10.2460/javma.244.8.914.
The subclinical impact of bovine leukemia virus (BLV) on the sustainability of the US dairy industry is only now being fully recognized. Findings of recent longitudinal studies conducted in Michigan dairy herds were consistent with the results of previous studies in showing that within-herd prevalence of BLV-infected cattle was negatively associated with milk production and cow longevity. Risk factors relating to routes of hematogenous transmission such as the use of shared hypodermic needles, shared reproductive examination sleeves, and natural breeding were associated with BLV within-herd prevalence. Few US dairy producers know the prevalence of BLV-infected cattle in their herds or are aware of the insidious economic impact of BLV or the options for BLV control. As an increasing number of countries eradicate BLV from their cattle populations, restrictions on the movement of US cattle and cattle products will likely increase. Veterinarians should be aware of recent developments for screening serum and milk samples for antibodies against BLV and the results of research regarding the economic impact of BLV so they can advise their dairy clients of available alternatives for monitoring and controlling BLV infection.
牛白血病病毒(BLV)对美国乳制品行业可持续性的亚临床影响直到现在才得到充分认识。最近在密歇根州奶牛群中进行的纵向研究结果与之前的研究结果一致,表明牛群中感染BLV的牛的患病率与产奶量和奶牛寿命呈负相关。与血源性传播途径相关的风险因素,如共用皮下注射针头、共用生殖检查套管和自然交配,与牛群中BLV的患病率有关。很少有美国乳制品生产商知道他们牛群中感染BLV的牛的患病率,或者意识到BLV的潜在经济影响或控制BLV的选择。随着越来越多的国家在其牛群中根除BLV,对美国牛和牛产品流动的限制可能会增加。兽医应该了解用于筛查血清和牛奶样本中抗BLV抗体的最新进展以及关于BLV经济影响的研究结果,以便他们能够向乳制品客户提供监测和控制BLV感染的可用替代方案的建议。