[目的]产气荚膜梭菌可以通过消化道、外伤等多种途径感染犊牛,导致犊牛腹泻、猝死等。[方法]本试验采用现场调查、病理剖检和病料组织的涂片染色镜检等方法,对疑似梭菌感染导致犊牛死亡的病例进行确诊,然后采取了相应的综合防控方案。[结果]现场调查表明,该病的发病率为16.35%（34/208）,病死率为11.76%（4/34）,最后淘汰无治疗价值犊牛30 头;病死牛的肝脏、肠道内容物及肠系膜淋巴结等组织的涂片、瑞氏染色镜检结果表明,致病菌为革兰氏阳性,两端钝圆,具有明显的荚膜的粗大杆菌。[结论]综合现场调查、病史分析和细菌的形态学观察等,判定导致本次犊牛发病死亡的为产气荚膜梭菌感染,感染途径主要为采食成母牛剩草剩料、未发酵完全的裹包青贮的消化道传播,通过紧急免疫接种、停止饲喂污染的饲草料和饮水消毒等措施,有力地控制了该病的进一步蔓延。
[Objective]Clostridium perfringens can infect calves through various ways such as digestive tract and trauma,resulting in diarrhea and sudden death of calves.[Method]In this experiment, field investigation, pathological autopsy and smear staining microscopy of diseased tissues were used to diagnose the cases of calf death caused by suspected Clostridium perfringens infection,and then corresponding comprehensive prevention and control schemes were adopted.[Result]The field investigation showed that the incidence of the disease was 16.35 %（34 /208）,and the mortality rate was 11.76%（4/34）.Finally,30 calves without therapeutic value were eliminated. The results of smear and Wright 's staining microscopy of liver,intestinal contents,mesenteric lymph nodes and other tissues of dead cattle showed that the pathogenic bacteria were Gram-positive,rounded at both ends,with obvious capsule of coarse bacilli.[Conclusion]Based on the field investigation,medical history analysis and morphological observation of bacteria,it was determined that the infection of Clostridium perfringens was the cause of the death of calves. The main route of infection was the digestive tract transmission of feeding cow residues and unfermented wrapped silage.Through emergency immunization,stopping feeding contaminated forage and drinking water disinfection, the further spread of the disease was effectively controlled.
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