Blanchard J L, Wescott R B
Am J Vet Res. 1985 Oct;46(10):2136-40.
Two experiments were performed to determine whether previous infection of young lambs with Ostertagia circumcincta increased their resistance to the development of Haemonchus contortus and to explore alterations in the microenvironment of the abomasum related to the interaction. The parasitic infections were monitored with periodic fecal egg counts and by recovery and enumeration of parasites at necropsy of the lambs. Alteration of the microenvironment was examined by measurement of serum gastrin concentrations at critical times during both experiments. The results indicated that the numbers of H contortus were significantly (P less than 0.05) less in lambs which had O circumcincta infections before their exposure to H contortus. There was less reduction in lambs from which O circumcincta was removed (anthelmintic therapy) before their exposure to H contortus. Fecal egg counts also were significantly (P less than 0.05) less in the former group of lambs (exposed to both parasites) than those in lambs exposed only to H contortus. Serum gastrin values were significantly (P less than 0.05) increased in lambs infected with O circumcincta and indicated that the interaction observed could be due, in part, to alteration of abomasal pH.
进行了两项实验，以确定幼龄羔羊先前感染环形奥斯特他线虫是否会增强其对捻转血矛线虫发育的抵抗力，并探究与这种相互作用相关的皱胃微环境的变化。通过定期进行粪便虫卵计数以及在羔羊尸检时回收并计数寄生虫来监测寄生虫感染情况。在两项实验的关键时间点，通过测量血清胃泌素浓度来检查微环境的变化。结果表明，在暴露于捻转血矛线虫之前已感染环形奥斯特他线虫的羔羊中，捻转血矛线虫的数量显著减少（P<0.05）。在暴露于捻转血矛线虫之前已清除环形奥斯特他线虫（驱虫治疗）的羔羊中，数量减少的程度较小。在前一组同时暴露于两种寄生虫的羔羊中，粪便虫卵计数也显著少于仅暴露于捻转血矛线虫的羔羊（P<0.05）。感染环形奥斯特他线虫的羔羊血清胃泌素值显著升高（P<0.05），这表明观察到的相互作用可能部分归因于皱胃pH值的变化。
