摘要
2017年1~6月,某猪场约有10%的仔猪在断奶后发生慢性消瘦和腹泻,病死率高达80%。为确诊该猪场疾病,采用病理剖检、PCR/RT-PCR检测、细菌分离鉴定、免疫组化检测、组织病理学分析等方法对病猪进行了诊断。病理剖检发现,肺小叶间质增宽,肝易碎呈棕黄色,肠系膜水肿、肠黏膜面有纤维素性坏死物附着。组织病理学表现为化脓性肺炎、桥接型肝小叶中心坏死、间质性肾炎、坏死性肠炎。从病原学方面检测出猪繁殖与呼吸综合征病毒(PRRSV)、猪圆环病毒2型(PCV2)与沙门菌(Salm onella)这3种病原。综合病理学和病原学检测结果,认为沙门菌继发于PRRSV和PCV2感染,是造成该场猪群严重死亡的主要原因。
From January to June 2017,about 10% piglets develop chronic wasting and diarrhea after weaning with mortality rate 80% on a farm in Hubei Province.The gross pathology,PCR/RT-PCR,bacterial isolation and identification,immunohistochemistry and histopathological analysis were then carried out to diagnose the disease.Necropsy revealed that the main pathological change were edematous distention of the interlobular septa,fragile liver with yellow-brown discoloration,mesenteric edema,and fibrinous necrotic material adhere to the intestinal mucosa.Morphologic change were suppurative pneumonia,bridginghepaticcentrilobular necrosis,interstitial nephritis and fibrinonecrotic enteritis.In addition,porcine reproductive and respiratory syndrome virus(PRRSV),porcine circovirus type 2(PCV2)and Salmonella were respectively detected.According to the pathology and etiology results,Salmonella infection secondary to PRRSV and PCV2 might be the leading cause of high mortality in this case.
引文
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