鸡传染性支气管炎病毒半数感染量的测定

EID_(50)DTERMINATION OF AVIAN INFECTIOUS BRONCHITS VIRUS

用血凝试验（ＨＡ）来测定肾病变型传染性支气管炎地方毒株（ＩＢＶ—Ｌ）的半数感染量（ＥＩＤ＿（５０））。对ＩＢＶ的ＨＡ试验进行初步研究的结果表明，ＩＢＶ—Ｌ株未经胰酶处理不具有血凝性，经１％～２％胰酶处理２～３，小时具有凝集鸡红细胞的特性，且以０．７５％鸡红血球悬液凝集状态最佳，１％以上者血凝价明显降低，对于不同孔型微量反应板进行测定，以Ｕ型板凝集效果最好。在建立ＨＡ试验的基础上，作者利用ＨＡ试验和特征性病变两种方法分别测定ＩＢＶ—Ｌ的ＥＩＤ＿（５０），两种方法对比的结果相似。

The EID_(50)of avian infectious bronchits virus with kidney pathological change was determinated by hemagglutination(HA)test.The reesults of HA test showed that IBV-L has no HA characteristic without pancreatin treatment,but it has abvious HA character when it was treated with 1%-2% of pancreatin. The most sensitive agglutination was obtained whentreated with 0.75% red blood cell(RBC)of chicken.The agglutinating titre of HA test obviously droped when the RBC was over 1%. The'U'shape micro-agglutinating plate was better than the'V'shape.EID_(50)of IBV-L was determined by both methods of HA test and typical pathological change.The rsults of these two methods are similar.