摘要
新城疫病毒毒力的判定标准是根据国际上规定的 3项指标 ,即最小致死量致死鸡胚平均死亡时间 ( MDT)、 1日龄雏鸡脑内接种致病指数 ( ICPI)和 6周龄非免疫雏鸡静脉接种致病指数 ( IVPI)等加以评价。将分离到的 1 1株鹅副粘病毒中选取了其中 3株 ,即 HG97C5 、YG97F1 1 、YG98- 2 C4,按照新城疫病毒毒力判定的标准方法进行了一系列致病性试验。结果为 :3株鹅副粘病毒的 MDT分别为 56.7、52 .0、53 .2 ,ICPI分别为 1 .64、1 .69、1 .70 ,IVPI分别为 2 .62、2 .60、2 .60 ,表明这 3株鹅副粘病毒均具有与新城疫病毒速发型相类似的毒力。同时将鹅胚和鹅按照研究新城疫病毒毒力的方法进行了相应的毒力试验。结果为 :上述 3株鹅副粘病毒最小致死量致死 1 3日龄鹅胚的平均死亡时间分别为 68.8、67.4、70 .2 ,1日龄雏鹅脑内接种致病指数分别为 1 .52、1 .64、1 .66,6周龄非免疫雏鹅静脉接种致病指数分别为 1 .2 6、1 .65、1 .68。目前虽然没有鹅副粘病毒毒力判定标准 ,但从其对鸡和鹅的致病性检测结果表明这
The virulence of 3 goose paramyxovirus isolates (HG 97 C 5, YG 97 F 11 and YG 98 2 C 4) was determined using traditional virulence tests for Newcastle disease virus. Their mean death time (MDT) of chicken embryos were 56.7, 52.0 and 53.2, intracerebral pathogenicity index (ICPI) in day old chicks were 1.64, 1.69 and 1.70, and intravenous pathogenicity index (IVPI) in 6 week old chickens were 2.62, 2.60 and 2.60, respectively. Similar tests were also performed on goose embryos and geese for the three isolates with MDT of 68.8, 67.4 and 70.2, ICPI of 1.52, 1.64 and 1.66, and IVPI of 1 26, 1.65 and 1.68, respectively. These results indicated that the three isolates were highly pathogenic for both chickens and geese.