Rice C E, Smith H J
Can J Comp Med Vet Sci. 1966 Sep;30(9):245-50.
Complement-fixation (CF) tests with sonicated aqueous extracts of adult forms of five species of gastrointestinal nematodes as antigens have been made on serial biweekly bleedings from two groups of parasitized calves grazing on infected pastures during the 1963 or 1964 seasons. Three of these nematode species, Cooperia oncophora, Ostertagia ostertagi and Nematodirus helvetianus, were found in large numbers in most of these animals. The calves were negative serologically before being placed on pasture but within 2 to 4 weeks some had developed considerable CF activity with Cooperia and other nematode antigens. Ten calves died, however, before significant CF titres had been attained. Eight control calves in the 1963 or 1964 groups which were grazed on "clean" pastures, remained serologically negative during the summer and autumn months. Four of the six surviving exposed animals in the 1964 group showed a fall in CF activity during the winter months when they were stabled, whereas the six surviving controls developed low CF titres suggesting that they were becoming mildly parasitized. In the spring of 1965 CF titres began to rise in some of the previously exposed and control yearlings even before they were placed on infected pasture in June.
以五种胃肠道线虫成虫的超声处理水提取物为抗原，对1963年或1964年季节在受感染牧场放牧的两组受寄生虫感染的小牛每两周进行一次连续采血，进行补体结合（CF）试验。在大多数这些动物中发现了大量的三种线虫，即牛古柏线虫、奥氏奥斯特线虫和瑞士细颈线虫。这些小牛在放入牧场之前血清学检测为阴性，但在2至4周内，一些小牛对古柏线虫和其他线虫抗原产生了相当程度的CF活性。然而，有10头小牛在达到显著的CF滴度之前死亡。1963年或1964年组中在“清洁”牧场放牧的8头对照小牛在夏季和秋季血清学检测仍为阴性。在1964年组中，6头存活的受感染动物中有4头在冬季圈养时CF活性下降，而6头存活的对照小牛产生了低CF滴度，表明它们正受到轻度寄生虫感染。1965年春天，一些之前受感染的一岁小牛和对照一岁小牛甚至在6月放入受感染牧场之前CF滴度就开始上升。
