阿维菌素驱除猪体内寄生虫实验

用猪为实验对象，分为2个实验组和1个对照组，比较了阿维菌素1%的注射液和伊维菌素1%的注射液，驱除猪体内寄生虫的效果。结果驱虫后第9天，粪便中线虫虫卵的转阴率均为100%，线虫虫卵减少率均为100%，表明阿维菌素能有效驱除猪体内线虫，且达到伊维菌素驱除体内线虫的效果。两种药物对妊娠母猪的怀孕和哺乳仔猪没有产生可见影响。     

碘硝酚药物驱除牛体内寄生虫的试验

牛胃肠道线虫病不仅影响幼牛生长发育,而且降低生产肉产乳性能,感染严重时导致牛瘦弱,拉稀,贫血乃至死亡,据调查赤峰地区牛胃肠道线虫感染率达100％,一般强度在百条乃至数千条上。笔者于1992年9月11月用碘硝酚药物进行了驱除牛体内寄生虫的药效试验,结果报告如下 1 材料和方法 1.1 试验材料 1.1.1 药物 20％碘硝酚注射液,系沈阳市兽药厂生产并提供。     

阿维菌素注射液驱杀牦牛体内外寄生虫试验

阿维菌素注射液驱杀牦牛体内外寄生虫试验胡义，保广祺，马增义，祁文珍，芦明辉，王国兴（青海省海北州牧科所，海晏，８１０２００）（海北州同宝牧场）阿维菌素（Ａｖｅｒｍｅｃｔｉｎ）是８０年代国外广泛应用的高效、广谱家畜驱虫药。近年来，我国正在开发阿维菌素产...     

灭虫净对绵羊体内外寄生虫驱除效果试验

寄生虫对家畜的危害性十分严重,它们种类多(可以有几种甚至几十种同时存在于一个家畜体内),散布广泛,常以一种极为隐蔽的方式摧残动物的身体健康,损害其繁殖机能,抑制幼畜的生长发育,从而大大削弱家畜的生产性能,降低畜产品的数量和质量.寄生虫对绵羊的危害特别严重,主要表现为脱毛严重,幼畜生长发育缓慢,成畜膘情不好,母畜空胎多等.过去使用的驱虫药物主要是左旋咪唑、敌百虫等,1995年以来开始使用丙硫苯咪唑,效果比左旋咪唑、敌百虫好,但是它们只对驱除绵羊体内寄生虫效果好,驱除家畜体表寄生虫方面效果不佳,绵羊掉毛依然严重.     

应用阿维菌素混悬粉剂驱除绵羊内外寄生虫试验

应用阿维菌素混悬粉剂驱除绵羊内外寄生虫试验李伟，裴青生，刘振伟，王爱萍，李晓卉（青海省畜牧兽医科学院西宁，８１０００３）近年来，我省各地使用阿维菌素驱除牛羊内外寄生虫，效果较为理想，但由于此药品难溶于水，剂型较单一，在实际生产中使用很不方便。我们在１...     

怀化市牛寄生虫驱虫药物筛选试验

为探索牛寄生虫药物驱虫效果，筛选高效驱虫药物组合，在新晃，芷江两县分5个组进行山羊驱虫试验，结果：牛驱虫药物组合以硫双二氯酚 虫克星为佳，可作为大面积上驱虫的道选药物组。     

碘硝酚药物驱除羊体内寄生虫的试验

碘硝酚药物驱除羊体内寄生虫的试验宗泽君汪作民（赤峰市畜牧兽医科学研究所，０２４０３１）斯钦昭日格达古拉（巴林右旗幸福之路兽医站）昭日格图密西格（巴林右旗巴彦他拉兽医站）陈国庆①杨永润②牟亚洲＊＊王洪涛＊＊据调查，赤峰地区六月龄以上的放牧绵羊感染捻转血...     

阿维菌素和丙硫苯咪唑对巨晰体内寄生虫的驱除试验

用丙硫苯咪唑和阿维菌素对国家一级保护野生动物巨蜥进行驱进行驱虫试验，每种药物设2个剂量组，每组6个重复。口服丙硫苯咪唑40.0mg/kg剂量组的胃肠道线虫虫卵减少率和虫卵转阴率分别为91.49%和83.33%，20.0mg/kg的剂量无效。皮下注射阿维菌素0.3mg/kg和0.6mg/kg剂量组的胃肠道线虫虫卵减少率和虫卵阴率均达100%。试验结果表明，用丙硫苯咪唑驱除巨蜥消化道线虫需较高剂量，较小剂量的阿维菌素对驱除巨蜥消化道线虫效果很好。     

阿维菌素驱杀牛疥螨的效果观察

以自然患有疥螨病的黄牛为试验动物，分别用1％阿维菌素注射和1％伊维菌素注射液按每千克体重0．02mL的剂量颈部皮下注射，各治疗一组，另设一个对照组。用药后第7天、重复用药一次，观察阿维菌素的驱虫效果。用药后第14、21、28天虫体转阴率为100％。该药对妊娠母牛、哺乳母牛、哺乳犊牛均无不良影响。     

Efficacy of ivermectin against Dermatobia hominis in cattle

Dermatobia hominis, the tropical warble fly, is one of the most important ectoparasites of cattle in Latin America. The results of five trials conducted in Paraguay, Brazil and Colombia showed that ivermectin administered subcutaneously at a dose level of 200 mcg/kg body weight was highly effective against the three larval stages of D. hominis in cattle.     

Efficacy of an in-feed preparation of ivermectin against endoparasites and scabies mites in swine.

In 2 trials, the efficacy of an in-feed preparation of ivermectin was evaluated in 40 pigs naturally infected with endoparasites and Sarcoptes scabiei var suis. Treated pigs (n = 10 in each trial) were fed a ration containing 2 ppm ivermectin for 7 days, followed by consumption of a nonmedicated ration for the remainder of the trial. Control pigs (n = 10 in each trial) were fed a complete, nonmedicated ration for the duration of the trial. Pigs in trial A were monitored for 14 days after treatment; those in trial B were monitored for 35 days after treatment. In trial A, treatment efficacy of ivermectin was 100% against Ascaris suum, Physocephalus sexalatus, Oesophagostomum dentatum, O brevicaudum, Metastrongylus spp; 99.8% against Ascarops strongylina; 90.9% against Trichuris suis; and 13.1% against Macracanthorhynchus hirudinaceus. At the terminus of the trial, statistically significant (P less than 0.05) differences were observed between numbers of treated and control pigs infected with A suum, Ascarops strongylina, and Oesophagostomum spp. On posttreatment day 14, S scabiei were not found in any scrapings taken from treated pigs, but were found in scrapings from 3 of 10 control pigs. The number of infested pigs in the treatment group was not statistically different from the number of infested pigs in the control group. In trial B, treatment efficacy was 100% for A suum and Metastrongylus spp; 96.9% for Ascarops strongylina; and 76.9% for M hirudinaceus. At the terminus of the trial, statistically significant (P less than 0.05) differences were evident between numbers of treated and control pigs infected with A suum, Ascarops strongylina, and Metastrongylus spp.(ABSTRACT TRUNCATED AT 250 WORDS)     

Efficacy of a topical formulation of eprinomectin against endoparasites of cattle in New Zealand

Two controlled studies involving 24 cattle were conducted in New Zealand to determine the efficacy of a topical, non-flammable formulation of eprinomectin against induced and naturally acquired nematode infections. In Trial 1, nematode infections were induced on Day -5 with third-stage larvae of Cooperia spp., Haemonchus contortus, Ostertagia ostertagi and Trichostrongvlus colubriformis so that the nematodes would be at the fourth larval stage when the cattle were treated. In Trial 2, cattle had naturally acquired nematode infections as determined by faecal nematode egg counts and larval cultures. The cattle were allocated on Day 0 (Trial 1) or Day 6 (Trial 2) on a stratified random basis according to bodyweight to one of two treatments: untreated control or eprinomectin (0.5% w/v) applied topically at 1 ml/10 kg bodyweight. Necropsies were undertaken on Days 14 and 15 and total nematode counts were done. In Trial 1, cattle treated with eprinomectin had significantly (p < 0.05) fewer Cooperia spp. and O. ostertagi than the controls. Larvae of H. contortus and T. colubriformis did not establish. In Trial 2, cattle treated with eprinomectin had significantly (p < 0.05) fewer of the following parasites than the controls: Haemonchus spp. (adult), Cooperia surnabada (adult), C. oncophora (adult), Cooperia spp. (L,), Ostertagia lyrata (adult), O. ostertagi (adult), Oesophagostomum spp. (adult), T. avei (adult and L1) and Trichuris spp. (adult). Reductions of 100% were observed for Capilfaria spp. (adult), D. viviparus (adult and L,), and Nematodirus helvetianus (adult), but these were not statistically significant (p > 0.05) because four or fewer control animals were infected with these parasites. In Trial 2, efficacies of greater than 99% were observed against all species for which moderate to high burdens occurred in the untreated controls. These findings indicate that eprinomectin in a topical formulation is a highly effective nematocide in cattle.     

Efficacy of ivermectin and levamisole against immature Dictyocaulus viviparus in cattle

Eighteen calves aged approximately three months were each infected with Dictyocaulus viviparus larvae at a rate of 30/kg bodyweight. Seven days later they were randomly allocated to three groups of six animals. Calves of group 1 were controls. Calves of group 2 were given levamisole at a dose rate of 10 mg/kg and calves of group 3 were given ivermectin at a dose rate of 200 micrograms/kg. The anthelmintic activity of these two drugs was compared using clinical, functional, parasitological and pathological parameters. The results showed that the efficacy of ivermectin, given at a therapeutic dose, against immature D viviparus was higher than that of levamisole, given at double the recommended dose.     

Efficacy of topically administered ivermectin against chorioptic and sarcoptic mange of cattle

The efficacy of topically administered ivermectin against Chorioptes bovis and Sarcoptes scabiei var bovis on cattle was evaluated in five studies involving a total of 68 cattle. Treatment with ivermectin solution at a dose rate of 500 micrograms/kg bodyweight topically once was fully effective against C bovis and S scabiei when applied to healthy skin. Efficacy against S scabiei was impaired when the formulation was applied over areas of severe lesions caused by this parasite, presumably due to reduced absorption of ivermectin.     

Efficacy of ivermectin against Parafilaria bovicola and lesion resolution in cattle.

Thirty-two cattle were included in a study to confirm the efficacy of ivermectin administered at 200 μg kg⁻¹ against Parafilaria bovicola and to determine the time required for resolution of the lesions caused by the parasite. Four treated and four control animals were slaughtered over 2 days starting 15, 30, 50 or 70 days after treatment. The number, distribution and surface area of carcass lesions, and the weight of tissue trimmed to render the carcasses aesthetically acceptable, were recorded and parasites were recovered from subcutaneous tissues.

Significantly (P < 0.01) fewer worms were recovered from ivermectin-treated cattle slaughtered 50 or 70 days after treatment than from controls. Reductions in the mean number and surface area of lesions, and in the weight of tissue trimmed, were statistically significant (P < 0.05) for the ivermectin-treated group slaughtered 70 days after treatment and approached significance (P < 0.1) for the ivermectin group slaughtered 50 days after treatment.     

Efficacy of ivermectin administered via sustained-release bolus against gastrointestinal nematodes in cattle

Twelve calves (mean weight, 175.5 kg) were used to confirm efficacy of ivermectin delivered from a prototype sustained-release bolus against naturally acquired gastrointestinal nematodes including early fourth-stage (inhibited) larvae of Ostertagia ostertagi. The calves were allocated by restricted randomization on weight to 1 of 2 groups: controls, to which a placebo bolus was given orally, and treated calves, to which a sustained-release bolus designed to deliver 8 mg of ivermectin/day at a steady rate was given orally. After treatment, the 2 groups were housed in separate pens with concrete flooring. Twenty-eight days after treatment, all calves were euthanatized and necropsied. The ivermectin-treated calves had no larval or adult Ostertagia spp and significantly (P less than 0.01) fewer adult Trichostrongylus axei and adult Cooperia (C oncophora, C punctata and C surnabada) than control calves. Efficacy of ivermectin was greater than 99% for Cooperia spp, and 100% for other parasites. Drug-related adverse reactions were not observed.     

Efficacy of a topical formulation of ivermectin against naturally acquired gastro-intestinal nematodes in weaner cattle

The efficacy of a topical formulation of ivermectin against naturally acquired gastro-intestinal nematodes in weaner cattle was evaluated. At slaughter, 14-15 days after treatment, burdens of Ostertagia spp, Trichostrongylus axei and Oesophagostomum radiatum were significantly lower in the treated calves than in the untreated controls (p<0.01). Efficacies (based on geometric mean worm burdens of treated and control groups) were 99.6%, 95.1% and 100% respectively. The sizes of the Cooperia spp and Trichuris ovis burdens in the treated group did not differ significantly at the 5% level of confidence from those in the control group.     

Efficacy of topically applied ivermectin against Boophilus microplus (Canestrini, 1887) in cattle

Systemic efficacy of ivermectin applied topically was evaluated against the cattle tick, Boophilus microplus. Twenty cattle with induced infestations were randomly allocated to five groups of equal size based on the numbers of engorged female ticks which fell through the slatted floor of individual pens during the 3 days prior to treatments. Control cattle were non-medicated. Cattle in three groups were given ivermectin at 200, 500 or 1000 mcg kg-1 in a topical formulation applied along the backline from the withers to the rump; cattle in the fifth group were given ivermectin in an injectable formulation subcutaneously at 200 mcg kg-1. Individual 24-h tick collections were made three times weekly for 5 weeks after treatment. Engorged female B. microplus were incubated to determine effects on reproduction. Based on the numbers of engorged female B. microplus collected following treatments, overall efficacy of ivermectin applied topically at 200, 500 and 1000 mcg kg-1 was 50, 85 and 91%, respectively, whereas ivermectin given at 200 mcg kg-1 subcutaneously was 80% effective. The index of reproduction for ivermectin given topically was reduced by 84, 94 and 95%, respectively, and that for ivermectin subcutaneously was 94%. No significant differences (P greater than 0.05) were found for these variables between ivermectin given topically at 500 or 1000 mcg kg-1 versus 200 mcg kg-1 given subcutaneously.     

Efficacy of ivermectin against benzimidazole-resistant nematodes of sheep

Two trials involving a total of 36 Dorset horn lambs were conducted to assess the anthelmintic efficacy of ivermectin against experimental infections of benzimidazole-resistant strains of Haemonchus contortus and Ostertagia circumcincta. Two resistant strains of each of the two species were used and in each trial the lambs were allocated to three groups. One group was given 200 micrograms ivermectin/kg bodyweight orally, the second group was given 5 mg oxfendazole/kg bodyweight orally and the third group remained untreated as controls. Fourteen days after treatment the lambs were necropsied. Ivermectin was found to be more than 99 per cent to 100 per cent effective against all four benzimidazole-resistant strains, whereas oxfendazole was 78.6 per cent and 83.8 per cent effective against the H contortus strains, and 25.6 per cent and 39.8 per cent effective against the O circumcincta strains.