Rugg D, Gogolewski R P, Barrick R A, Eagleson J S
Merck Sharp and Dohme Veterinary Research and Development Laboratory, Ingleburn, NSW.
Aust Vet J. 1997 Jan;75(1):36-8. doi: 10.1111/j.1751-0813.1997.tb13828.x.
To investigate the therapeutic and prophylactic efficacy of an ivermectin controlled-release capsule against nasal bots (Oestrus ovis) in sheep.
Trial 1--A pen study with controls. Trial 2--A field study with controls.
Trial 1--Forty Merino wethers with natural infestations of nasal bot were used. Trial 2--One hundred nasal bot-free wethers were used.
Trial 1--Ten randomly selected animals were slaughtered and the heads split and examined to confirm bot infestation. Fifteen animals were allocated to untreated controls and 15 to treatment with a controlled-release capsule delivering ivermectin at > or = 20 micrograms/kg/day for 100 days. Twenty-nine days after treatment the sheep were killed and examined for nasal bots. Trial 2--Nasal bot-free sheep were allocated to two groups of 45 animals. One group was untreated the other sheep were treated with capsules as above. The sheep were grazed as a single group exposed to natural challenge from O ovis. Ninety days after treatment the animals were slaughtered and examined for nasal bot infestation.
Trial 1--Live O ovis larvae were recovered from 60% of control sheep. No live larvae were collected from treated sheep. Trial 2--Forty-one percent of untreated sheep harbored nasal bot infestations. No live larvae were collected from any treated animal.
Treatment with a single ivermectin controlled release capsule was 100% effective against existing infestations of O ovis and as a prophylactic treatment for this parasite.
研究伊维菌素控释胶囊对绵羊鼻蝇蛆（羊狂蝇）的治疗和预防效果。
试验1——有对照的围栏试验。试验2——有对照的田间试验。
试验1——使用40只自然感染鼻蝇蛆的美利奴阉羊。试验2——使用100只未感染鼻蝇蛆的阉羊。
试验1——随机挑选10只动物宰杀，劈开头部检查以确认蝇蛆感染情况。15只动物分配到未治疗对照组，15只接受伊维菌素控释胶囊治疗，剂量≥20微克/千克/天，持续100天。治疗29天后，处死绵羊并检查鼻蝇蛆。试验2——未感染鼻蝇蛆的绵羊分为两组，每组45只。一组不治疗，另一组按上述方法用胶囊治疗。绵羊作为一个群体放牧，暴露于羊狂蝇的自然感染环境中。治疗90天后，宰杀动物并检查鼻蝇蛆感染情况。
试验1——60%的对照绵羊体内发现活的羊狂蝇幼虫。治疗组绵羊未发现活幼虫。试验2——41%的未治疗绵羊感染鼻蝇蛆。治疗组动物均未发现活幼虫。
单次使用伊维菌素控释胶囊治疗对现有的羊狂蝇感染100%有效，且可作为该寄生虫的预防性治疗。
