中文摘要：

为了观察鸡新城疫（Newcastle disease,ND）、传染性法氏囊病（Infectious bursal disease,IBD）二联灭活疫苗免疫效果,使用鸡新城疫、传染性法氏囊病（HQ株）二联灭活疫苗免疫1日龄SPF鸡与商品蛋鸡,分别于免后第7~91天,每隔1周采血1次,监测传染性法氏囊病毒中和抗体,同时进行传染性法氏囊病毒强毒攻毒,观察免疫后的法氏囊中和抗体消涨情况及不同日龄的攻毒保护情况。结果表明：SPF鸡组免疫后IBD抗体快速上升,免疫后2周法氏囊抗体达到10 lb左右,免疫后4周达到14 lb以上,抗体维持到免疫后第91天,从免疫后5周开始到7周攻毒保护率达到100%。而商品蛋鸡组IBD母源抗体在免疫后2周下降至10 lb左右,在免疫后4周抗体达到13 lb;免疫5周后攻毒保护率达到80%以上。说明鸡新城疫、传染性法氏囊病二联灭活疫苗免疫要在免后4周才能达到较好的保护效果。

英文摘要：

To observe the immune effect of combined inactived vaccine of chicken Newcastle disease （ ND ） and infectious bursal disease （IBD）, one -day -old SPF chickens and commercial layer were immunized with ND -1BD combined inactived vaccine （HQ strain）. Blood samples were collected once every other week from 7 to 91 d after immunization for monitoring virus - neutralizing antibodies to infectious bursal disease virus （IBDV）, respectively. At the same time, the IBDV virulent challenge was carried out to observe the growth and decline of virus - neutralizing antibodies to IBDV after immunization and the challenge protection in the chickens at different days of age. The results showed that the antibody levels of IBD in the SPF chicken group began to rise rapidly after immunization, and reached 10 lb or so and above 14 lb on the second week and the 4th week after immutlization, respectively. The IBD antibody remained at 91 days after immunization, and the chal- lenge protection rate reached 100% from the 5th to 7th week after immunization. However, the maternal antibody levels of IBD in the commer- cial layer group declined to 10 lb or so on the second week and reached above 13 lb on the 4th week after immunization. The challenge protec- tion rate in the commercial layer group reached above 80% on the 5th week after immunization. It is thus clear that hetter protection effect can be achieved on the 4th week after immunization with NB - IBD combined inactived vaccine.