BVDV对后备牛生长发育状况及繁殖性能的影响

牛病毒性腹泻/黏膜病(BVD/MD)是一种严重危害奶牛健康的病毒性传染病,其病原为牛病毒性腹泻病毒(BVDV)。BVDV感染牛后主要表现两种状态,即一过性感染(TI)和持续性感染(PI)。BVD在牛场的流行,可严重影响奶牛的生产性能、繁殖性能及牛群健康状况,对奶牛的影响可表现为流产、胎儿畸形、腹泻和免疫抑制等。怀孕母牛在特定妊娠阶段感染BVDV后,可娩出PI犊牛,部分PI犊牛能像正常犊牛一样生长发育至成年,但其生长发育状况和繁殖性能较同龄健康牛差异十分明显。为评价BVDV对后备牛生长发育及繁殖状况的影响,笔者采用ELISA方法检出北京地区28个规模化奶牛场141头BVDV-PI牛,并与同龄健康牛生长发育及繁殖数据相比较,结果表明,BVDV-PI后备牛各月龄段的体高、体重均低于健康后备牛,其首次输精日龄、配准日龄、耗精量明显高于健康后备牛,而一次情期受胎率显著低于健康后备牛。数据显示,BVDV严重影响后备牛的生长发育及繁殖状况。

Effects of BVDV on Growth and Reproductive Performance in Heifers

Bovine viral diarrhea/mucosal disease is one of the most important viral diseases which severe damage the health of cattle. The pathogen of BVD is bovine viral diarrhea virus, represented the prototype member of the pestivirus genus, family Flaviviridae. The genome is made up of a single molecule of linear positive-sense single-stranded ribonucleic acid （RNA） molecule. BVDV infection has two main types, transient infection （TI） and persistent infection （PI）. BVD （bovine viral diarrhoea） virus can cause significant damage to cattle health, fertility and productivity. BVDV can cause abortion, diarrhea, malformations, immunosuppression, and so on. Fetal infections in the special stage of gestation may generate persistent infection calves. Some of the PI calves will grow normal like healthy calves, but the growth and reproductive performance is not ideal. In this article, we discuss how BVDV influences growth and reproductive performance in young cattle. Dairy cows and young animals from 28 farms had been tested by ELISA-Ag in Beijing, and 141 animals had been detected. Compare with healthy animals, the BVDV-PI heifers have low height and weight in all stages, and low first service age, conception age, average service times and the conception rate of first service. The results showed that BVDV can influence growth and reproductive performance in young animals seriously.