鸡传染性支气管炎嗜肾性BF株病毒的分离与鉴定

Isolation and Identification of a Nephrotropic BF Strain of Infectious Bronchitis Virus

从北京地区某鸡场２５日龄海赛克斯商品蛋鸡群分离到一株嗜肾性鸡传染性支气管炎病毒（ＢＦ株）。经ＳＰＦ鸡胚连续传２５代后，毒价可达１０６．５～１０７．５。理化鉴定表明，ＢＦ株病毒耐酸性能强，而对碱和乙醚较敏感。５０％氯仿能使病毒完全失活。５６℃处理１小时，病毒仍有感染性。ＢＦ株鸡胚传代毒回归１０日龄ＳＰＦ鸡引起小鸡１００％发病和死亡。死鸡肾肿大，尿酸盐沉积于输尿管和肾小管。病毒在蔗糖溶液中的浮密度为１．１５８３ｇ／ｍｌ。血清学鉴定表明，血清与病毒交叉中和试验ＢＦ株与Ｍ４１、Ｉｏｗａ６０９、Ｃｏｎｎ４６以及一些野外分离株之间具有单项或双项交叉反应。电镜形态学观察为圆形和梨型，边沿不规则，有纤突。

s A strain of avian infectious bronchilis virus (BF strain) which was predominantly nephrotropic, was isolated from a farm in Beijing. After 25 passages in SPF chicken embryos, the EID 50 was 10 6 5 ￣10 7 5 /0.1ml. Some of its physicochemical properties were identified, BF was resistant to pH 3.0 senstive to pH 11.0 and completely inativated by chloroform. Exposuring to ether, titer of the virus reduced. It still maintained its infectivity after heatedin 56℃ for one hour. The buoyant density of the virus was 1.1583g/ml in sucrose gradient. Virus neutralization test indicated that BF strain had single or multiple cross reactivities with M 41 、Iow609、 Conn46 strains and some other field isolates.