奶牛淋巴细胞毒抗体的研究

本文用微量淋巴细胞毒试验方法检测了两个牛场的502头黑白花奶牛对淋巴细胞毒抗体出现的时间、阳性率及阳性血清的反应频率进行了研究。从已配种而未分娩的母牛至五胎以上的怀孕母牛均进行了检测。淋巴细胞毒抗血清的总阳性率为44.2％(223/502)。各胎次母牛出现的阳性率,差异不显著。但二胎以下组与三胎以上组相比较,血清阳性率各为34.7％和50.7％,差异极显著(P<0.001)。怀孕母牛的淋巴细胞毒抗体在第三胎以上开始大量出现。同时对阳性血清的反应频率进行了分析。反应频率在21-40％这一范围的阳性血清最多,占总阳性血清的36.8％,与其他反应频率范围的阳性血清之间均有显著或极显著差异,21-40％这一反应频率对筛选分型血清是较为合适的。

STUDIES ON THE LYMPHOCYTOTOXIC ANTIBODIES ( LTA ) OF DAIRY CATTLE

Sera from 502 Black & White dairy cows in two farms were tes-ted by microlymphocytotoxic met- hod. The total positive percentage of LTA was 44.2% ( 223/502 ). The differences between different parities were insignificant ( except between primigravida and the 4th parity ) . However, the difference becween those under the 2nd parity group (34.7%, including the 2nd parity ) and those over the 2nd parity group ( 50.7% ) was very significant ( P<.001 ) , and at the 3rd parity the LTA began to app-ear in a large proportion. Besides, the frequencies of positive reacti-ons in the positive sera were mai-nly in the range of 21% to 40%, in which positive sera accounted for 36.8% of the total. This group was very different from other gr-oups ( P<.001 ) .