犊牛支原体肺炎继发牛A型多杀性巴氏杆菌感染的诊治

某奶牛场犊牛相继发生肺炎和关节炎,为确诊该牛场犊牛群发病的原因并提出防控方案,本试验剖检新生犊牛并采集病料,分别开展牛支原体及其他病原菌的分离培养、PCR鉴定及药敏分析;进行牛病毒性腹泻病毒、牛口蹄疫病毒和牛传染性鼻气管炎病毒PCR检测;制作犊牛肺脏组织病理切片并进行观察和评估。从犊牛肺脏组织分离到牛支原体和牛A型多杀性巴氏杆菌;牛病毒性腹泻病毒、牛口蹄疫病毒和牛传染性鼻气管炎病毒检测均为阴性;肺脏组织病理切片可见肺泡结构破坏、出血及大量炎性细胞浸润;药敏试验结果显示,牛支原体和牛A型多杀性巴氏杆菌分别对泰乐菌素和头孢唑啉敏感,但对青霉素、庆大霉素、林可霉素和氨苄西林均呈现耐药。该犊牛群确诊为牛支原体肺炎继发牛A型多杀性巴氏杆菌感染,采用泰乐菌素联合头孢唑啉肌肉注射,配合对症治疗和规范管理,有效控制了该场犊牛疾病。

Diagnosis and Treatment of Mycoplasma bovis Pneumonia with Bovine Capsular Serotype A Pasteurella multocida Infection in Calf

The assay was aimed to clarify the reasons why pneumonia and arthritis had happened in a dairy farm,and provide effective control and treatment.A newborn calf was autopsied and the samples were collected.Mycoplasma bovis (M.bovis) and other pathogens were isolated and cultured,and PCR identification and drug sensitivity test were performed.Bovine viral diarrhea virus (BVDV),foot-and-mouth disease virus (FMDV) and infectious bovine rhinotracheitis virus (IBRV) were detected by PCR.Pathological slices from calf lung tissue were made to evaluate pathological changes.M.bovis and bovine capsular serotype A Pasteurella multocida (Pm A) were isolated,respectively.There were negative results for BVDV,FMDV and IBRV detection.Pathological slices of lung tissue showed damaged visible alveolar structure,bleeding and a large number of inflammatory cells infiltration.Drug sensitivity test results showed that M.bovis and Pm A were sensitive to tylosin and cefazolin,respectively,but resistance to penicillin,gentamicin,clindamycin and ampicillin.It was confirmed that M.bovis pneumonia with Pm A infection had happened.The disease in the farm was controlled by using tylosin and cefazolin at the same time.Furthermore,symptomatic treatment and standardized management should be carried.