【摘要】 对初生雏鸡的AI母源抗体进行了动态观察 ,并在HI效价为 6 (Log2 )和 4 (Log2 )、2 (Log2 )左右时 ,分别应用禽流感病毒进行攻毒。结果显示 :初生雏鸡AI母源抗体HI效价的峰值在 7日龄时 (7.85 (Log2 ) )出现 ,比 1日龄 (6 .8(Log2 ) )时高出 1个倍比滴度 ;7日龄后HI效价即随雏鸡日龄的增加而迅速下降 ;至 2 8日龄时 ,已趋于消失。攻毒试验中 ,当HI效价为 6 (Log2 )左右时 ,其保护率为 10 0 % ;在 4 (Log2 )时 ,保护率仅为 5 0 % ;在 2 (Log2 )左右时 ,保护率只有2 0 %。由此说明 ,能使雏鸡对AIV的攻击获得完全保护的临界值应在 4 (Log2 )～ 6 (Log2 )之间 ,且必须大于 4 (Log2 )。更多还原

【Abstract】 Avian influenza(AI)maternal HI antibody were tested regularly in new birth chicken,and when the average HI titers were 6Log2?4Log2 and 2Log2,chicken were challenged with AIV separately.The results showed that the peak of HI titer(7.85Log2)appeared on the 7th day.It was higher one times than HI titer on the 1st day(6.8Log2).After the 7th day,the HI titer decreased fast with the chicken growing.Until the 28th day,HI antibody vanished fundamentally.When HI titers were 6Log2?4Log2 and2Log2,the protective rate were 100%?50%?20%respectively. It can be concluded that the lowest HI titer which can prevent chicken from AIV should be 4Log2 to 6Log2,and must be higher than 4Log2.更多还原