海兰褐蛋鸡产气荚膜梭菌的分离鉴定

Isolation and Identification of Clostridium perfringens from Hy-Line Variety Brown Laying Hens

近期山东省青岛市即墨区某蛋鸡场内350日龄的海兰褐蛋鸡出现了鸡只消瘦、精神沉郁、腹泻、便血等症状。根据其发病突然死亡快及刨检后肠管明显肿胀,肠壁变薄,肠道内容物为混有血液的褐色和黑色稀粪等特点确诊为鸡坏死性肠炎病。产气荚膜梭菌作为该病的主要病原菌,可导致蛋鸡死淘率增加,经济效益降低及产蛋率下降。为了探究产气荚膜梭菌的生物学特性,试验收集了该鸡场20只病鸡的肠道内容物。通过稀释培养、生理生化试验、16S rRNA测序及多重PCR等方法进行产气荚膜梭菌的分离鉴定。结果表明:试验中分离出的产气荚膜梭菌(H1~H7)同源性均在99.86%~100%之间,且均为A型,因此认为导致该鸡场发生的坏死性肠炎的产气荚膜梭菌可能是A型产气荚膜梭菌。研究可为蛋鸡坏死性肠炎的诊断及鸡场的免疫防治提供理论依据,促进蛋鸡养殖业的经济发展。

Recently,350-day-old Hy-Line brown laying hens in a laying farm in Jimo District,Qingdao city,Shandong province,developed symptoms such as weight loss,depression,diarrhea and blood in stool.According to the characteristics of sudden onset,rapid death,obvious swelling of intestinal tube,thinning of intestinal wall,and brown and black feces mixed with blood,the disease was diagnosed as necrotizing enteritis.C.perfringens,as the main pathogen of the disease,could increase the mortality,reduce the economic benefit and decrease the egg production rate of laying hens.In order to study the biological characteristics of C.perfringens,the intestinal contents of 20 diseased laying hens were collected.C.perfringens was isolated and identified by dilution culture,physiological and biochemical tests,16S rRNA sequencing and multiplex PCR.The results showed that the homology of C.perfringens(H1~H7)isolated in this experiment was 99.86%~100%,and they were all type A.Therefore,we believed that C.perfringens,which caused necrotizing enteritis in this laying hens farm,might be type A C.perfringens.This study could provide a theoretical basis for the diagnosis of necrotizing enteritis in laying hens and the prevention and control of the disease in layer farms.