Eysker M
Vet Parasitol. 1986 Nov;22(1-2):95-103. doi: 10.1016/0304-4017(86)90011-7.
In two grazing experiments carried out in 1982 and 1983 the prophylactic effect on gastro-intestinal helminthiasis of a single ivermectin treatment of calves 3 weeks after turnout was studied in animals which were turned out early on contaminated pasture and in calves which were turned out late on mown pasture. A single ivermectin treatment 3 weeks after early turnout did not prevent heavy helminth infections. However, such single treatment of calves 3 weeks after a late turnout on mown pasture appears to be a promising way of preventing heavy infections. Late turnout on mown pasture without anthelmintic treatment was not enough to prevent heavy infections. Ivermectin treatment was more effective against Ostertagia spp. than against Cooperia spp. There was no effect on the faecal egg output of Nematodirus helvetianus. Predominantly due to the dry summer, infections were lighter in 1983 than in 1982. These lower infections, and possibly also a delay in the onset of inhibition and differences in helminth strains, may explain the lower proportion of inhibited development in Ostertagia spp. in 1983 than in the comparable groups in 1982.
在1982年和1983年进行的两项放牧实验中，对在受污染牧场上早放牧的犊牛以及在割草后的牧场上晚放牧的犊牛，研究了在放牧3周后对犊牛进行单次伊维菌素治疗对胃肠蠕虫病的预防效果。早放牧3周后进行单次伊维菌素治疗并不能预防严重的蠕虫感染。然而，在割草后的牧场上晚放牧3周后对犊牛进行这种单次治疗似乎是预防严重感染的一种有前景的方法。在割草后的牧场上晚放牧但不进行驱虫治疗不足以预防严重感染。伊维菌素治疗对奥斯特他线虫属的效果比对古柏线虫属的效果更好。对瑞士细颈线虫的粪便虫卵排出量没有影响。主要由于夏季干旱，1983年的感染比1982年轻。这些较低的感染率，以及可能还有抑制作用开始的延迟和蠕虫菌株的差异，可能解释了1983年奥斯特他线虫属中发育受抑制的比例低于1982年可比组的原因。
