鸡新城疫-传染性法氏囊病-禽流感(H9亚型)三联灭活疫苗对雏鸡的免疫效力研究

Study on Immune Efficacies of A Trivalent Inactivated Vaccine against Newcastle Disease,Infectious Bursal Disease and Avian Influenza(Subtype H9) in Chicks

为了评估鸡新城疫(ND)-传染性法氏囊病(IBD)-禽流感(AI)(H9亚型)三联灭活疫苗对雏鸡的免疫效力,采用该疫苗分别免疫1、7、10、14、21日龄SPF雏鸡和带有母源抗体的普通雏鸡,免疫后21d^28d采血测定ND血凝抑制抗体(HIAb)、IBD中和抗体(NA)及AI(H9)HIAb抗体,并用传染性法氏囊病病毒(IBDV)强毒攻击。结果显示,免疫后各不同日龄免疫组SPF雏鸡的ND HIAb、IBD NA及AI(H9)HIAb滴度分别为7.9log2~8.3log2、13.9log2~15.8log2及8.0log2~8.9log2,IBDV攻毒均100%保护;而普通雏鸡免疫后的ND HIAb、IBD NA及AI(H9)HIAb滴度,1日龄免疫组分别为5.9log2、12.1log2和5.6log2,7、10、14、21日龄免疫组分别为6.1log2~7.0log2、12.6log2~14.5log2和6.0log2~7.5log2;IBDV攻毒,1日龄免疫组普通雏鸡保护率为60%,7、14及21日龄免疫组保护率均为100%;结果证实,SPF雏鸡所产生的免疫效力要高于带有母源抗体的普通雏鸡,1日龄普通雏鸡免疫所产生的免疫效力明显低于其他日龄。根据试验结果,推荐该疫苗对雏鸡的使用日龄为7日龄~14日龄。

To evaluate immune efficacy of a trivalent inactivated vaccine against Newcastle disease（ND）,infectious bursal disease（IBD）and avian influenza（AI）（subtype H9）,the vaccine was administered to SPF chicks and common healthy chicks with maternal antibodies at ages of 1,7,10,14 and 21-day-old.The blood samples of the chicks were collected at 21-28 days after vaccination,then ND haemagglutination inhibition antibody（HIAb）,IBD neutralizing antibody（NA）and AI（H9）HIAb were examined,and the virulent IBDV challenge was carried out.The experimental results showed that for SPF chicks vaccinated at ages of 1,7,10,14 and 21-day-old,ND HIAb,IBD NA and AI（H9）HIAb titers were 7.9 to 8.3,13.9 to 15.8 and 8.0 to8.9 log2,respectively,protection rates against IBDV challenge were 100%;that for common healthy birds vaccinated at 1-day-old,ND HIAb,IBD NA and AI（H9）HIAb titers were 5.9,12.1 and 5.6 log2;that for common healthy birds vaccinated at ages of 7,10,14 and 21-day-old,ND HIAb,IBD NA and AI（H9）HIAb titers were 6.1 to 7.0,12.6 to 14.5 and 6.0 to 7.5 log2,the protection rate against IBDV challenge,in common healthy birds vaccinated at 1-day-old was 60%,in common healthy birds vaccinated at ages of 7,10,14 and 21-day-old were 100%.The results confirmed that the immune efficacy in vaccinated SPF chicks was higher than that in the common chicks carrying maternal antibodies,the immune efficacy in vaccinated1-day-old common chicks was significantly lower than that in the other ages of common chicks.In accordance with the trial data,the vaccine is recommended to give to chicks at ages of 7 to 14-day-old.