新疆某牧场牛病毒性腹泻的诊断及防控

Diagnosis and control of bovine viral diarrhea in a pasture in Xinjiang

中文关键词: 牛病毒性腹泻  诊断  免疫防控

英文关键词: Bovine viral diarrhea  Diagnosis  The immune prevention and control

中文摘要:

      为了查明新疆某规模化牧场犊牛发病死亡的原因，本试验采用现场流行病学调查结合实验室检测方法进行研究。结果表明，该病的发病率为39.43％，病死率为32.14％，易感牛群主要是3月龄以内的犊牛，具有典型BVD症状，病理变化以消化道症状为主，病死牛肠道有大量出血点、肠黏膜溃疡、脱落、肠壁菲薄、胃肠道内容物中有大量气泡、肠系膜淋巴结肿大等；RT-PCR检测结果表明4份病死犊牛的肠组织、32份发病犊牛和3份（3/10）同群亚健康犊牛肠内容物核酸均为阳性；序列对比分析结果表明，该牧场感染的病毒为BVDV-1a型，与Genbank上登陆的部分BVDV-1型参考株的同源性为88.0％-98.4％，与部分BVDV-2型参考株的同源性为31.5％-43.7％；结合实验室检测及临床防控需求，牧场采取了净化阳性牛结合BVD-IBR二联疫苗免疫的方式有效地控制了该病的进一步发生。

英文摘要:

      In order to find out the cause of morbidity and mortality of calves in a large-scale pasture in xinjiang, this study was conducted by combining field epidemiological investigation with rt-pcr detection and sequence analysis.Results show that the incidence of the disease was 39.43%, the fatality rate was 32.14%, the susceptible herds mainly calf within 3 months of age, there are vertical and horizontal two transmission modes, pathological changes is given priority to with gastrointestinal symptoms, illness cow intestines have massive haemorrhage, intestinal mucosa ulcer, fall off, intestinal wall thinning, there is a lot of bubbles in the gastrointestinal contents, mesenteric lymph node enlargement, etc;The results of rt-pcr showed that the intestinal tissues of 4 diseased dead calves, 32 diseased calves and 3 (3/10) of the same group of sub-healthy calves were all positive.The results of sequence comparison and analysis showed that the virus infected in the farm was of type bvdv-1a, with a homology of 88.0%-98.4% with some reference strains of type bvdv-1 that landed on Genbank, and 31.5-43.7% with some reference strains of type bvdv-2.In combination with laboratory testing and clinical control requirements, the farm adopted the method of purifying positive cattle and immunizing them with bvd-ibr vaccine to effectively control the further occurrence of the disease.