规模化蛋鸡场H9N2亚型禽流感疫苗免疫效果调查

FIELD EFFICANY OF H9 SUBTYPE AVIAN INFLUENZA VACCINE IN LAYING HENS IN HUBEI

为了解湖北省规模化蛋鸡场H9N2亚型禽流感疫苗的免疫效果,本研究在2014年1月至12月从湖北省13个地区选择不同规模化蛋鸡场,随机采集蛋鸡血样2189份,用血凝抑制(hemagglutination inhibition,HI)试验测定了H9N2亚型禽流感抗体滴度。对样本检测结果进行统计与分析显示,1月份到5月份样本HI抗体滴度平均值呈上升趋势,1月份检测的样本抗体滴度最低,为9.26log2,5月份检测的样本抗体滴度最高,为12.34log2。13个不同地区样本抗体滴度存在一定的差异,抗体滴度最低地区的平均值为5.76log2,滴度最高地区为11.58log2。对不同日龄蛋鸡样本检测结果分析显示,随着日龄增长,样本平均抗体滴度值呈现逐渐上升趋势,蛋鸡日龄≤120 d的样本抗体滴度平均值最低,为10.21log2,300日龄以上的蛋鸡样本抗体滴度平均值最高,为11.31log2。检测结果表明,湖北省规模化蛋鸡场H9N2亚型禽流感的平均抗体滴度值水平总体良好,合格率和优秀率较高,但不同地区、不同日龄和不同月份蛋鸡H9N2亚型禽流感抗体存在差异。

In order to investigate the immune effect of H9N2 subtype avian influenza vaccine on large-scale layer farms in Hubei province, 2189 blood samples were randomly collected from January to December 2014 from poultry farms in 13 regions. The antibody titers of H9N2 subtype Avian infl uenza virus were determined in hemagglutination inhibition test（HI）. The results showed a rising trend of the average HI antibody titers from January to May. The antibody titers were the lowest（9.26log2） in January and the highest（12.34log2） in May. In addition, there were some differences between 13 different regions with the lowest antibody titer at 5.76log2 and the highest titer at 11.58log2. The results also showed that the average antibody titers increased gradually with the aging. The average antibody titer was the lowest at 10.21log2 when chicken were less than 120 days old while the average antibody titer was the highest at 11.31log2 when the hens were more than 300 days old. The investigation concluded that the antibody level of H9N2 subtype avian infl uenza vaccine was good in general good and the qualifi ed or excellent immune protection was relatively high on layer farms in Hubei province. However, some differences in the antibody titers of H9N2 subtype avian infl uenza vaccine were observed in different regions, ages and months of the year.