进口海兰褐祖代鸡禽白血病感染状态的持续观察及与国内发病鸡群种蛋p27检出率、病毒分离率的相关性

Long-term inspection on imported egg-type grandparent breeder chicken for avian leukosis virus infection status and relatedness comparison of p27 and virus isolation positive rates

对自国外直接进口的蛋用型海兰褐祖代鸡群的禽白血病感染状态进行了持续观察,并与国内3个不同发病状况的海兰褐父母代鸡群的种蛋p27检出率、抗体阳性率、投诉情况进行了比较。将国外直接进口的蛋用型海兰褐祖代鸡群3个配套系240只1日龄鸡在SPF环境中饲养,在不同日龄采集泄殖腔棉拭子检测禽白血病病毒(A-vian leukosis virus,ALV)群特异性p27抗原、采集血清检测ALV-AB及J特异性抗体和采集血浆分离外源性ALV,并在鸡群开产后收集种蛋,检测蛋清p27抗原和父母代鸡群胎粪p27抗原。同时对来自天津、山东的不同投诉情况的3个父母代鸡场种蛋p27抗原或ALV-AB及J抗体进行了检测。结果显示,进口祖代鸡ALV-AB及J特异性抗体在68、150日龄检测均为阴性;分别在12、26、68、150日龄采血浆在DF1细胞分离病毒均为阴性;收集的250枚种蛋蛋清和孵化的父母代鸡群胎粪p27抗原检测均为阴性。而其他国内3个父母代鸡场的种蛋p27检出率最高达12%。结果表明,该海兰褐祖代鸡群无外源性禽白血病的感染,不同鸡群的种蛋p27检出率与病毒分离率及发病情况具有较好的吻合性,可以作为开展ALV的流行病学调查和种鸡场净化的重要指标。

To inspect imported egg-type grandparent breeder chicks for their avian leukosis virus（ALV） infection status,and compare the relatedness between p27 and virus isolation positive rate of parent breeder chicks from three domestic farms with different condition of complaints.Two hundred and forty one-day-old chicks of 3 varieties were kept and raised in SPF isolators.The cloaca swabs,blood plasma and sera were collected at different ages during raising period.They were tested for p27 antigen,antibodies and virus isolation.Collect eggs after they begin laying,detect p27 antigen in egg white and meconium of parent breeder chicks.At the same time,chicks from the three farms（Tianjin,Shandong） were tested for p27 antigen,ALV-AB and J antibodies.The results indicated that the positive rates of p27 antigen were different among 3 varieties of the grandparent breeders.All the chicks of all varieties were negative to ALV-AB antibody and ALV-J antibody at 68 d and 150 d.Plasma samples were collected at 12,26,68 and 150 d of age and inoculated into DF1 cells,no exogenous virus were isolated from all chickes.All hatching eggs collected were negative to p27 detection,so as meconium of the parent breeders.While the positive rate of p27 is up to 12% of the other three parent breeder chicks.The results demonstrated that there was no exogenous avian leukosis virus（ALV） infection in this egg-type grandparent breeder chicks and the incidence rate is well consistent with p27 and virus isolation positive rates.This experiment can be helpful for the detection and isolation of ALV.