Wardhaugh K G, Mahon R J, Ahmad H B
CSIRO Entomology, PO Box 1700, Canberra, Australian Capital Territory 2601.
Aust Vet J. 2001 Feb;79(2):120-4. doi: 10.1111/j.1751-0813.2001.tb10720.x.
To assess the efficacy of four macrocyclic lactones for the control of larvae of the Old World Screw-worm Fly (OWS), Chrysomya bezziana, and to examine the effects of excreted residues on the dung fauna.
100 heifers were divided into five groups of 20 animals. One group remained untreated, whereas the other groups were treated respectively with pour-on formulations of moxidectin, eprinomectin or doramectin, or a sustained-release bolus of ivermectin.
At intervals of 1 to 15 weeks after treatment, five cattle from each group were challenged with newly-laid eggs of OWS. The efficacy of each treatment was determined 48 h later by comparing the number of myiases in the treated and untreated groups. Abundance of fly larvae in naturally-voided dung pads and the survival of a species of dung beetle, Onthophagus sagittarius, were used to assess the effects of drug residues on the dung fauna.
Moxidectin showed no activity against larvae of OWS during the first 14 days after treatment. Eprinomectin provided protection for 3 days after dosing, but failed at days 7 and 14, whereas doramectin was effective at day 7, but not at days 14 or 21. In contrast, no myiases were established on bolus-treated cattle from 14 to 102 days after treatment. Faecal residues of moxidectin had no effect on the survival of larvae of dung-feeding flies, whereas those of eprinomectin and doramectin reduced survival for 1 to 2 weeks. Dung voided by bolus-treated cattle inhibited fly breeding and had adverse effects on the development and survival of O sagittarius for up to 15 weeks after treatment.
评估四种大环内酯类药物对旧大陆螺旋锥蝇（OWS，嗜人瘤蝇蛆）幼虫的防治效果，并研究排泄残留物对粪便动物群落的影响。
100头小母牛被分为五组，每组20头。一组不进行处理，而其他组分别用莫昔克丁、依普菌素或多拉菌素的浇泼剂配方进行处理，或用伊维菌素缓释丸剂进行处理。
处理后每隔1至15周，每组选取5头牛用新产的OWS卵进行攻毒。48小时后，通过比较处理组和未处理组的蝇蛆病数量来确定每种处理方法的效果。利用自然排出的粪堆中蝇幼虫的数量以及一种蜣螂（箭头嗡蜣螂）的存活率来评估药物残留对粪便动物群落的影响。
莫昔克丁在处理后的前14天对OWS幼虫无活性。依普菌素给药后提供了3天的保护，但在第7天和第14天失效，而多拉菌素在第7天有效，但在第14天或第21天无效。相比之下，用丸剂处理的牛在处理后14至102天未出现蝇蛆病。莫昔克丁的粪便残留物对以粪便为食的蝇幼虫存活率没有影响，而依普菌素和多拉菌素的残留物使存活率降低了1至2周。用丸剂处理的牛排出的粪便在处理后长达15周内抑制了苍蝇繁殖，并对箭头嗡蜣螂的发育和存活产生了不利影响。
