北京地区犊牛腹泻主要病原调查及综合防控

发布时间：2018-01-15 23:16

本文关键词：北京地区犊牛腹泻主要病原调查及综合防控　出处：《中国农业大学》2016年博士论文　论文类型：学位论文

【摘要】：犊牛腹泻是导致犊牛死亡的主要原因。论文对北京地区犊牛腹泻的流行情况和死亡情况进行了调查,对引起犊牛腹泻的主要病原进行了病原学研究,通过制定综合防控措施,为北京市奶牛业的健康发展提供保障。对北京地区奶牛场的犊牛发病记录进行了统计分析,犊牛腹泻的平均发病率为18.80%,平均死亡率为2.45%。在北京8个主要区县对30个牛场犊牛的986份血样和3360份腹泻粪样进行了检测,结果显示：牛病毒性腹泻病毒血清抗体阳性率为24.44%；粪样中轮状病毒检出率为11.10%,冠状病毒为2.20%,隐孢子虫为7.23%,致病性大肠杆菌为5.71%,轮状病毒和隐孢子虫是最主要的混合感染形式,占混合感染的35.00%。对球虫的流行病学调查结果表明,采自30个奶牛场的2307份粪样中,球虫平均感染率为23.88%,平均OPG值为549,所有牛场均存在感染。形态学鉴定出7种艾美尔属球虫,分别为邱氏艾美尔球虫(检出率33.01%)、牛艾美尔球虫(31.09%)、椭圆艾美尔球虫(25.32%)、加拿大艾美尔球虫(2.53%)、亚球形艾美尔球虫(4.41%)、柱状艾美尔球虫(1.34%)、拨克朗艾美尔球虫(1.45%)。发病的犊牛多为多种球虫混合感染,主要致病虫种为邱氏艾美尔球虫。对贾第虫和隐孢子虫的流行病学调查结果显示,在调查的822份奶牛粪样中,14份呈现贾第虫感染阳性,感染率为1.09%,以0-6月龄的犊牛贾第虫感染率最高,北京贾第虫分离株经PCR方法鉴定为基因型E,与河南分离株亲缘关系最近。隐孢子虫感染率为2.55%,包括安氏隐孢子虫和微小隐孢子虫,后者为犊牛优势虫种,属于人畜共患的ⅡdA1SG1基因亚型。根据病原学研究和流行病学调查,按照预防为主的防控原则,制定了以生物隔离区和健康养殖规范为核心,快速诊断与治疗应急措施为支撑的综合管理方案,并进行了推广,取得了可喜的成效。三年来,北京地区犊牛腹泻的发病率由原来的20.58%下降为16.82%,死亡率由2.90%下降为1.85%。
[Abstract]:Calves diarrhea is the main cause of calves death. This paper investigated the prevalence and death of calf diarrhea in Beijing area, and studied the etiology of the main pathogens causing calf diarrhea. Through the establishment of comprehensive prevention and control measures to provide protection for the healthy development of the dairy industry in Beijing. The incidence of calves in Beijing dairy farm was statistically analyzed. The average incidence of diarrhea in calves was 18.80%. The average mortality rate was 2.45. 986 blood samples and 3360 fecal samples of 30 calves from cattle farms in 8 major districts of Beijing were tested. The results showed that the positive rate of serum antibody against bovine viral diarrhea virus was 24.44. The detection rates of rotavirus, coronavirus, cryptosporidium and pathogenic Escherichia coli were 11.10, 2.20, 7.23 and 5.71% respectively. Rotavirus and Cryptosporidium were the main mixed infection forms, which accounted for 35.00.The epidemiological investigation of coccidiosis showed that the rotavirus and Cryptosporidium were collected from 2307 feces from 30 dairy farms. The average infection rate of coccidia was 23.888.The average OPG value was 549.The 7 species of Eimeria were identified by morphology. They were Eimeria Qiu (detection rate 33.01), Eimeria bovis (31.09), Eimeria ellipticus 25.32 (Canada 2.53). Eimeria subglobularis 4.41, Eimeria columnalis 1.34, Eimeria koraiensis 1.455.The most of the calves were infected with multiple coccidia. The main pathogenic species was Eimeria Qiu. Epidemiological investigation of giardia and Cryptosporidium showed that 14 of 822 samples of cow dung were positive for giardia infection. The infection rate of Giardia japonica was the highest in the calves aged 0-6 months. The isolates were identified as genotype E by PCR method. The infection rate of Cryptosporidium was 2.55, including Cryptosporidium andCryptosporidium, which was the dominant species of calves. According to etiology research and epidemiological investigation, according to the principle of prevention and control, the core of this study is biological isolation area and healthy breeding standard. Rapid diagnosis and treatment of emergency measures for the support of the integrated management plan, and has been promoted, and achieved gratifying results over the past three years. The incidence of diarrhea in Beijing calves decreased from 20.58% to 16.82, and the mortality rate decreased from 2.90% to 1.85.
【学位授予单位】：中国农业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S858.23

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