禽流感H9亚型油乳剂灭活疫苗的改进

用新引进的 6株禽流感病毒 (AIV )H9亚型和现制苗用的AIV H9毒株分别制备AIV H9、AIV H5、NDV二联三价油乳剂灭活疫苗 ,免疫 5日龄和 10日龄雏鸡 ,于免疫当日直至 80日龄鸡出栏期间定期采血 ,用HI法检测相应的AIV H9、AIV H5和NDV抗体。结果表明 ,10日龄免疫鸡的AIV H9抗体效价最高 ,5日龄和 10日龄免疫鸡的AIV H5抗体效价差别不明显 ;用引进的 3号AIV H9毒株制备的联苗对 10日龄雏鸡免疫后 2 0d产生AIV H9保护性抗体 ,一直持续到 80日龄以上 ,期间的抗体平均效价为 6 .72 (lb) ,而现制苗用的AIV H9毒株制备的联苗免疫力较差 ;现制苗用的AIV H5毒株制备的联苗免疫效力仍较好 ;分别接种 0 .2 5、0 .30mL/只联苗的雏鸡AIV H5抗体效价没有明显差别 ,而AIV H9抗体效价以接种 0 .30mL/只剂量的为高 ;不同日龄、不同免疫剂量的试验鸡NDV抗体效价没有明显差异。

Improvement of the inactivated oil-emulsion vaccine against AIV-H9 subtype

Five-day-old and ten-day-old chicks were vaccinated with ND H_5 H_9 inactivated oil-(emulsion) triple-vaccine made respectively from 6 AIV strains isolated in Guangdong and 1 vaccine strain now being used in practice.At the day vaccinated and post-vaccination till for sale serums of all chickens were collected for ND,H_5 and H_9 HI antibody test. It was showed by the results that for H_9 ten-day-old chicks are suitable for vaccination,but for H_5 antibody titer was not remarkable difference between five-day-old chicks and ten-day-old chicks, that the vaccine No. 6(from Guangdong No. 3 strain ) induced effective immune protectivity since 20 days post vaccination which remained till over 50-80 days old and the hightest antibody level against H_9 which reached a average titer of 6.72lb from 31 days to 80 days old, that the immune efficacy of the H_9 vaccine for use now in practice was not very good,but the immune efficacy of the H_5 vaccine for use now in practice was very good, that the effect of the vaccination dose (0.30 mL per chick or (0.25) mL per chick) of the H_5 vaccine on the immune efficacy was not obvious, but the effect of the vaccination dose 0.30 mL per chick was better than that of 0.25 mL per chick for H_9, and that either the age for vaccination or the dose vaccinated had little effect on the immune efficacy of the ND vaccine.