Gasbarre L C, Leighton E A, Davies C J
USDA, ARS, Helminthic Diseases Laboratory, Beltsville, MD 20705.
Vet Parasitol. 1993 Feb;46(1-4):81-91. doi: 10.1016/0304-4017(93)90049-s.
Previous studies have shown that the number of gastrointestinal nematode eggs released per gram of feces (EPG) of calves is strongly influenced by host genetics. The purpose of this study was to determine if host genetics also influenced immune recognition of parasite antigens in these same calves. Serum samples were taken at monthly intervals from calves during their first grazing season, from approximately 4 months after the onset of calving and were continued until weaning. Serum samples were analyzed for antibodies against Ostertagia ostertagi, Haemonchus placei, Cooperia oncophora, and Oesophagostomum radiatum. Significant rises in antibodies of the IgG1 class were seen against Ostertagia ostertagi, H. placei, and C. oncophora. In addition, rises in anti-Ostertagia antibodies of the IgG2 and IgM isotypes were also noted. During periods of elevated antibody responses, the sire of the individual calves was found to influence significantly the level of circulating antibody. The heritability of serum anti-parasite antibody levels was demonstrated to be between 70 and 80%, depending upon the time and antibody isotype. The antibody levels did not appear to be correlated with parasite EPG values. These results indicate that the ability of calves to recognize parasite antigens is strongly influenced by genetic factors, and that the genetic factors which control antibody responses may differ from those controlling EPG values.
以往研究表明，犊牛每克粪便中排出的胃肠道线虫卵数量（每克粪便虫卵数，EPG）受宿主遗传学的强烈影响。本研究的目的是确定宿主遗传学是否也影响这些犊牛对寄生虫抗原的免疫识别。在犊牛第一个放牧季节，从产犊开始约4个月起，每月采集血清样本，持续至断奶。分析血清样本中针对奥斯特他线虫、牛血矛线虫、辐射食道口线虫和有齿库珀线虫的抗体。针对奥斯特他线虫、牛血矛线虫和有齿库珀线虫，观察到IgG1类抗体显著升高。此外，还注意到IgG2和IgM同种型的抗奥斯特他线虫抗体升高。在抗体反应升高期间，发现个体犊牛的父亲对循环抗体水平有显著影响。血清抗寄生虫抗体水平的遗传力在70%至80%之间，具体取决于时间和抗体同种型。抗体水平似乎与寄生虫EPG值无关。这些结果表明，犊牛识别寄生虫抗原的能力受遗传因素的强烈影响，且控制抗体反应的遗传因素可能与控制EPG值的因素不同。
