摘要
大肠杆菌K99引发的犊牛腹泻给养牛产业造成了巨大的经济损失,本研究为调查K99流行情况,自2020年8月至2021年7月从呼和浩特市周边7个规模化牛场随机采集380份粪样和血样,采用PCR和ELISA方法进行K99抗原抗体流行情况调查,对PCR检测阳性样品进行分离培养,经形态学、生化试验、菌毛特异基因扩增以及测序鉴定K99分离株,进一步通过药敏试验评价药物敏感性。结果显示,380份粪样中PCR检测K99阳性样品25份,阳性率6.58%;380份血样中ELISA检测阳性99份,阳性率为26%,阳性血样多集中于0~2月龄犊牛,阳性率达到48.28%。菌毛基因PCR测序鉴定了8株K99菌株,药敏结果显示,分离株对庆大霉素、氧氟沙星、链霉素、丁胺卡那、卡那霉素敏感。调查结果表明,呼和浩特市周边地区牛群中存在K99感染,且多发于0~2月龄犊牛,为养殖户临床合理用药以及进行疫病防控提供参考。
Calf diarrhea caused by Escherichia coli K99 has caused huge economic losses to the cattle industry.In order to investigate the prevalence of K99,380 fecal and blood samples were randomly collected from 7 large-scale cattle farms around Hohhot from August 2020 to July 2021.The prevalence of K99 antigen and antibody in this area was investigated by PCR and ELISA.PCR positive samples were isolated and cultured.K99 isolate was identified by morphology,biochemical test,pili specific gene amplification and sequencing,and the drug sensitivity was further evaluated by drug sensitivity test,so as to provide reference basis for clinical rational application of antibiotics and formulation of prevention and treatment measures.The results showed that 25 out of 380 fecal samples were K99 positive by PCR,and the positive rate was 6.58%.Among 380 blood samples,99 positive blood samples were detected by ELISA,and the positive rate was 26%.Most of them were observed in 0~2 months old calves,and the positive rate was 48.28%.Eight strains of K99 were identified by PCR sequencing of pili gene.The drug sensitivity results showed that the isolates were sensitive to gentamicin,ofloxacin,streptomycin,amikacin and kanamycin.This study indicates that K99 infection exists in calves with diarrhea in the surrounding areas of Hohhot.The most common cases were 0 to 2 months of age.It provides reference for the farmers to appropriately use medicine clinically and to prevent the disease.
作者
刘平平
谢梦圆
李文豪
郝彦儒
王建龙
王旭红
徐晓静
LIU Pingping;XIE Mengyuan;LI Wenhao;HAO Yanru;WANG Jianlong;WANG Xuhong;XU Xiaojing(College of Veterinary Medicine,Inner Mongolia Agricultural University,Hohhot,Inner Mongolia 010000;Inner Mongolia Animal Disease Prevention and Control Center,Hohhot,Inner Mongolia 010000,China)
出处
《家畜生态学报》
北大核心
2023年第12期69-73,共5页
Journal of Domestic Animal Ecology
基金
内蒙古自治区科技重大专项(2020ZD0006)。
