伊维菌素对绵羊体表寄生虫的影响

为了研究伊维菌素浇泼剂对绵羊体表寄生虫的效果,本实验在不同温度下应用0.5%伊维菌素浇泼剂按0.2、0.5、0.8mg/kg·bw剂量对绵羊沿背中线皮肤一次浇泼给药,并以不浇泼伊维菌素做对照,以羊颚虱和羊蜱蝇转阴率为考察指标,评判不同剂量和不同温度下伊维菌素浇泼剂驱杀绵羊体表寄生虫效果。实验结果表明,0.2mg/kg·bw、0.5mg/kg·bw和0.8mg/kg·bw伊维菌素浇泼剂对羊颚虱转阴率分别为95%、100%和100%,对羊蜱蝇转阴率分别为81.3%、85.7%和92.8%。随着平均温度从13.8℃升高到28.9℃,伊维菌素对羊颚虱和羊蜱蝇转阴率逐渐降低。     

伊维菌素浇泼剂对绵羊线虫的驱虫效力与安全性试验

应用0.5%伊维菌素浇泼剂按0.3,0.4,0.5mg/kg.b w剂量对绵羊沿背中线皮肤一次浇泼给药,并以伊维菌素注射剂0.2mg/kg.b w剂量做对照。结果:伊维菌素浇泼剂0.3mg/kg,0.4mg/kg.b w剂量对消化道线虫虫卵转阴率分别为85%和90%,减少率分别为89.1%和95.9%;对原圆科线虫幼虫转阴率分别为60%和75%,减少率分别为77.2%和86.7%;0.5mg/kg.b w剂量对消化道线虫虫卵转阴率和减少率均为100%,对原圆科线虫幼虫转阴率为85%,减少率为95.4%。解剖检查结果:伊维菌素浇泼剂三种剂量对绵羊消化道、呼吸道多属线虫均有效,总计驱虫率分别为90.8%,95.6%和99.7%,伊维菌素浇泼剂0.5mg/kg.b w剂量与伊维菌素注射剂0.2mg/kg.b w剂量驱虫效果基本一致;绵羊经皮给药可耐受1.0mg/kg.b w剂量。试验证明:伊维菌素浇泼剂经皮给药驱除绵羊线虫高效安全,临床推荐剂量以0.5mg/kg.b w为宜。     

伊维菌素浇泼剂对牦牛胃肠道线虫的驱除效果

在甘肃省肃南县大河乡大岔村选择自然感染胃肠道线虫的1-2岁牦牛75头,随机分为5组,每组15头,Ⅰ、Ⅱ、Ⅲ组分别为伊维菌素浇泼剂试验组,分别按0.3、0.4、0.5 mg/kg体重剂量经背部皮肤浇泼给药;Ⅳ组为伊维菌素注射剂对照组,按0.2 mg/kg体重剂量皮下注射给药;Ⅴ组为空白对照组。另随机挑选牦牛10头供安全性观察,随机分为2组,每组5头,分别为伊维菌素浇泼剂0.7 mg/kg和1.0 mg/kg体重剂量试验组,经背部皮肤浇泼给药。结果表明：以0.5 mg/kg体重剂量伊维菌素浇泼剂对牦牛胃肠道线虫驱治效果最好,其虫卵转阴率、减少率和驱虫率分别达100%、100%和99.25%,对毛首线虫驱虫率为96.00%;0.3 mg/kg和0.4 mg/kg体重剂量伊维菌素浇泼剂的驱虫效果均低于0.5 mg/kg体重剂量组,且呈现驱虫效果随着药物剂量的增加而提高。同时,试验使用1.0 mg/kg体重剂量伊维菌素浇泼剂,所用试验牦牛给药后精神、呼吸、采食、排粪、运动等情况未见异常反应,表明本品毒性较低,临床使用安全高效。     

伊维菌素浇泼剂对肃南牦牛胃肠道线虫的驱除效果试验

在肃南县大河乡大岔村选择自然感染胃肠道线虫的1~2岁牦牛75头,随机分为5组,每组15头,Ⅰ、Ⅱ、Ⅲ组分别为伊维菌素浇泼剂试验组,分别按0.3、0.4、0.5mg/kg体重剂量经背部皮肤浇泼给药;Ⅳ组为伊维菌素注射剂对照组,按0.2mg/kg体重剂量皮下注射给药;Ⅴ组为空白对照组。另随机挑选牦牛10头供安全性观察,随机分为2组,每组5头,Ⅰ、Ⅱ组分别为伊维菌素浇泼剂0.7、1.0mg/kg体重剂量试验组,经背部皮肤浇泼给药。通过对虫卵转阴率、虫卵减少率、粗计驱虫率、安全性观测的分析,结果表明:以0.5mg/kg体重剂量伊维菌素浇泼剂对牦牛胃肠道线虫驱治效果最好,其虫卵转阴率、减少率和驱虫率分别达到100%、100%和99.25%,对毛首线虫驱虫率为96.00%,0.3、0.4mg/kg体重剂量伊维菌素浇泼剂的驱虫效果均低于0.5mg/kg体重剂量组,且呈现驱虫效果随着药物剂量的增加而提高。同时,本次试验使用1mg/kg体重剂量伊维菌素浇泼剂,所用试验牦牛给药后精神、呼吸、采食、排粪、运动等情况未见异常反应,表明本品毒性较低,临床使用安全高效。     

伊维菌素浇泼剂治疗猪疥螨病的效果观察

应用0.5%伊维菌素浇泼剂,按0.1~0.12mL/kg剂量治疗112头疥螨病患猪。结果表明,给药后14d治愈率达100%。     

伊维菌素注射剂与浇泼剂驱除藏犬肠道线虫的疗效

应用伊维菌素注射剂与浇泼剂,驱除藏犬肠道线虫,并用粪检法检查其疗效。结果表明：伊维菌素注射剂0.2mg/kg剂量对藏犬肠道线虫的虫卵转阴率与减少率均为100.0%;伊维菌素浇泼剂0.5mg/kg剂量转阴率及减少率为100%。     

伊维菌素浇泼剂防治绵羊寄生虫病的效果观察

应用伊维菌素浇泼剂,驱除绵羊体内线虫和体外寄生虫,结果表明,0．5mg／kg体重剂量对主要7属消化道线虫和网尾线虫的虫卵（幼虫）转阴率、减少率均为100％,对原圆科线虫幼虫转阴率、减少率分别为87．59／6和91．3％,对线虫的总计驱虫率为99．04％;对绵羊颚虱的杀虫率达100％。表明伊维菌素浇泼剂0．5mg／kg剂量一次用药,驱除绵羊体内线虫和体外绵羊颚虱等寄生虫,高效安全。     

伊维菌素注射液、浇泼剂与敌百虫溶液治疗新西兰兔疥螨病的效果观察

将患疥螨病的新西兰兔100只,随机分成A、B、C、D、E 5组,每组20只,A组按每千克体重皮下注射0.2 mg伊维菌素治疗,间隔10d重复1次;B组用伊维菌素浇泼剂溶液直接喷浇涂抹在患病部位,1日1次,连用3d;C组先用伊维菌素浇泼剂溶液直接喷浇涂抹2 d后再按每千克体重皮下注射0.2 mg伊维菌素治疗1次;D组用2%浓度敌百虫溶液对患部涂擦,每天2次,连用3 d;E组用2%浓度敌百虫溶液涂擦2 d后再按每千克体重皮下注射0.2 mg伊维菌素治疗1次。结果表明,5组治愈率分别为85%、90%、100%、75%、100%。A组增重14.3%,B组增重18.9%,C组增重20.3%,D组增重11.1%,E组增重20.0%。经方差分析,C组、E组分别与A组、B组、D组间差异极显著(P<0.01);C组与E组间差异不显著(P>0.05)。试验得出以伊维菌素+浇泼剂组和伊维菌素+敌百虫组效果显著。     

牦牛主要寄生虫病高效低残留防治技术试验示范

为评价埃谱利诺菌素浇泼剂的驱虫效果与对牦牛线虫病及外寄生虫病的防治示范应用效果,选择1.5岁感染线虫和部分外寄生虫的牦牛150头,设埃谱利诺菌素浇泼剂0.4、0.5和0.6 mg/kg体重剂量组和埃谱利诺菌素注射剂对照组,进行驱虫效果评价;按0.5mg/kg体重剂量进行规模防治技术示范,检查防治效果和考核防治效益。结果:药效试验中埃谱利诺菌素浇泼剂0.5 mg/kg对牦牛消化道线虫虫卵转阴率、减少率分别为96.7%和99.3%,对原圆科线虫幼虫转阴率和减少率分别为90.0%和97.8%;0.6 mg/kg剂量对消化道线虫虫卵及原圆科线虫幼虫转阴率和减少率均为100.0%;0.4mg/kg剂量对消化道线虫虫卵转阴率为83.0%,减少率为90.4%,原圆科线虫幼虫转阴率和减少率分别为76.7%和88.9%。在冬季应用埃谱利诺菌素浇泼剂按0.5 mg/kg体重剂量对牦牛进行规模防治技术示范,近期防治示范群牦牛消化道线虫虫卵转阴率为96.7%,虫卵减少率为97.7%;对原圆科线虫幼虫转阴率、减少率分别为93.3%和97.6%。远期防治效果达88.5%。同期检查未防治对照组牦牛虫卵EPG和幼虫数略有增加。埃谱利诺菌素浇泼剂0.5mg/kg剂量试验组给药后第1d牦牛体表的牛颚虱活力减弱;第3d牛颚虱大部分死亡干瘪,部分虫体处于麻痹状态,活力较差;第7d检查牛颚虱全部死亡干瘪,杀灭率达100%;0.4mg/kg剂量,第3、7d检查杀灭效果次于上述剂量。而未防治的对照组牦牛上述外寄生虫活力旺盛,感染情况与给药前无明显变化。检查技术示范群比未示范群每头成年牦牛平均多增重或少减重5.76kg、幼年牛成活率平均提高2.51个百分点。结果表明该防治技术对牦牛主要寄生虫病高效安全低残留,效益显著。     

不同剂量的伊维菌素注射剂和浇泼剂对天祝牦牛牛皮蝇防制效果观察

通过对天祝县感染了牛皮蝇的牦牛的药物实验,确定了伊维菌素注射剂与浇泼剂在防治该病时的最低剂量。将280头牦牛随机分成7组,1~3组分别在颈部皮下注射0.1%伊维菌素注射液1μg/kg,5μg/kg和10μg/kg,4~6组分别沿背中线浇泼0.5%伊维菌素浇泼剂25μg/kg、50μg/kg和250μg/kg,将第7组设为空白对照。对前6组在11月份统一治疗。在第2年的3月份和5月份检查试验牦牛的背部瘤包,在治疗组牛的背部未发现瘤包,但在对照组牛的背部发现了三期幼虫。结果表明：1μg/kg伊维菌素注射剂和25μg/kg的浇泼剂对自然感染的牛皮蝇幼虫有较好的防治效果。     

害获灭注射剂对猪体内外寄生虫的驱虫试验

应用害获灭注射剂分别按0.2、0.3、0.4mg/kg剂量经皮下注射给药,进行对猪自然感染寄生虫的驱除效果观察。结果：在给药后7、14d临床检查,0.2mg/kg剂量对猪血虱驱虫效果达中效;0.3、0.4mg/kg剂量对猪血虱的驱虫率均达100.00%,用药后至出栏的几个月内未出现复发。在给药后14d粪检,0.2mg/kg剂量组对猪蛔虫虫卵减少率为89.57%;0.3、0.4mg/kg组虫卵减少率均达100.00%。表明害获灭注射剂0.3、0.4mg/kg剂量驱除猪蛔虫和猪血虱高效安全。     

A survey of gastrointestinal parasites in pigs of the Plateau and Rivers States, Nigeria

Faecal samples were collected from a total of 1,000 pigs from the Port Harcourt and Jos areas of the Rivers and Plateau States, respectively, between January 1987 and March 1988. In the Jos area the parasite incidence was: Ascaris suum 53.1%, Trichuris suis 8.5%, Hyostrongylus rubidus 13.1%, Metastrongylus salmi 3.7%, Strongyloides ransomi 87.7%, Oesophagostomum dentatum 35.1% and Eimeria spp. 2.4% while in Port Harcourt the incidence rate was Ascaris suum 10.4%, Trichuris suis 47.2%, Oesophagostomum dentatum 50%, Hyostrongylus rubidus 2%, Ancylostoma duodenale 83.2% and Eimeria spp. 3.6%. The high rate of parasitic infections was due to poor management practices as shown by poor sanitary conditions. Access to human faeces, poor feeding and lack of deworming were also very evident. The different rates in the incidence of parasites in Jos and Port Harcourt areas were due to the varying moisture conditions in these states.     

Evaluation of a serodiagnostic test using Ascaris suum haemoglobin for the detection of roundworm infections in pig populations

The significant economical consequences of infections with Ascaris suum in pigs are already well documented. However, due to the subclinical nature of the disease and the lack of practical diagnostic means, ascariasis often remains undiagnosed. Here we describe the development and evaluation of a novel indirect ELISA using the purified A. suum haemoglobin (AsHb) molecule as an antigen. Initial validation using sera from 190 pigs experimentally infected twice a week with A. suum and Trichuris suis (25 and 5eggskg(-1)day(-1) respectively) demonstrated that the AsHb ELISA is able to detect long-term exposure to A. suum with a high sensitivity and specificity (99.5% and 100.0% respectively). Furthermore, this serological technique proved to be more sensitive than faecal examination on week 7 and 14 of the experiment (99.5% and 100% compared to 59.5% and 68.4% respectively). Cross-reactivity caused by T. suis infection was shown to be limited after analysing sera from pigs with an experimental T. suis mono-infection. Seroconversion was shown to occur from week 6 onwards in pigs receiving 100 A. suum eggs 5 times a week. Preliminary testing of the ELISA on six randomly selected farms confirmed the results obtained in the artificial infection trials, showing a higher sensitivity of the serologic method compared to faecal examination. Finally, the ELISA was used to investigate Ascaris infection rates on 101 conventional Flemish pig farms. The results showed that on 38.6% of the farms less than 20% of the tested samples were seropositive, while in 19.8% of the farms 80-100% of all pigs were seropositive. The results of this study suggest that the AsHb ELISA could provide pig farmers and veterinarians with an easier and more sensitive way to estimate the overall prevalence of A. suum on their farm.     

Evaluation of fenbendazole as an extended anthelmintic treatment regimen for swine

Fenbendazole was given in the feed to swine at a cumulative dosage of 9 mg/kg of body weight over a period of 3, 6, and 12 days to compare efficacy. Four treatment groups of ten 2- to 3-month-old pigs each, with a mean of 15 kg of body weight per group, received 3 mg of fenbendazole/kg/day for 3 days, 1.5 mg/kg/day for 6 days, 0.75 mg/kg/day for 12 days, and no medication. Medicated feed was scheduled so that all treated pigs reached the last day of treatment on the same day, thus making the time between the last treatment and necropsy equal for all groups. Ascaris suum and Trichuris suis were the target species, their presence before treatment being determined by fecal egg counts and at necropsy by worm counts. At necropsy, 9 control pigs were infected with A suum (mean of 18.0 worms/pig), and all control pigs had T suis infection (mean of 36.5 worms/pig). All 3 treatment schedules were 100% effective in removal of A suum; and for T suis, the 3-day regimen was 100% effective, the 6-day regimen, 99.2%, and the 12-day regimen, 91.0%.     

Effects of Mebendazole and Cambendazole on enterohelminths in pigs]

Mebendazole, administered at a dose of 30 mg active substance per 1 kg of feed, was found to have 100% effectiveness on Ascaris suum and Cambendazole, administered at a dose of 1.5 g per 1 kg of liver weight, showed the same effectiveness in the control of Ascaris suum and Oesophagostomum dentatum. The effectiveness of both drugs on Trichocephalus suis and Strongyloides ransomi was low. Mebendazole and Cambendazole can be recommended for mass dehelminthization of pigs in affected stocks. Helminthoovoscopical examination of sows and fattened pigs showed an 88.6% extensity of invasion in sows, and a 28.3% and 33.9% extensity in three- and five-month-old pigs, respectively. Coccidiosis was found in 51.4% of the sows and Balantidium coli had an occurrence rate of 80.7 to 98.2%.     

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 an in-feed ivermectin formulation against gastrointestinal helminths, lungworms, and sarcoptic mites in swine

The efficacy of ivermectin as an in-feed formulation was evaluated against naturally acquired gastrointestinal helminths, lungworms, and sarcoptic mites (experiment 1; n = 24) and against induced infection with intestinal nematodes (experiment 2; n = 24) in pigs. Treatments consisted of ivermectin administered in feed at concentrations calculated to provide 100 or 200 micrograms/kg of body weight/d for 7 days or of nonmedicated feed (controls) for 7 days. At concentration of 100 micrograms of ivermectin/kg/d, efficacy against naturally acquired infections was 97.7% for Ascaris suum, 97.8% for Metastrongylus spp, greater than 99% for Oesophagostomum spp, 100% for Macracanthorhynchus hirudinaceus, and 89.7% for Ascarops strongylina. Against induced infections (fourth-stage larvae), efficacy was 100% for A suum and 96.9% for Oesophagostomum spp. At concentration of 200 micrograms of ivermectin/kg/d, efficacy against naturally acquired infections was 100% for A suum, Hyostrongylus rubidus, Metastrongylus spp, and Ascarops strongylina; greater than 99% for Oesophagostomum spp; and 85.9% for Macracanthorhynchus hirudinaceus. Against induced infections (fourth-stage larvae), efficacy was 100% for A suum and 95% for Oesophagostomum spp. At concentrations of 100 and 200 micrograms of ivermectin/kg/d, efficacy against Sarcoptes scabiei var suis was evidenced by elimination of the mite by posttreatment day 14.     

Efficacy of dichlorvos, fenbendazole, and ivermectin in swine with induced intestinal nematode infections

Anthelmintic efficacies of dichlorvos, fenbendazole, and ivermectin were compared in specific-pathogen-free crossbred weanling pigs inoculated with Ascaris suum, Trichuris suis, and Oesophagostomum dentatum. On postinoculation day (PID) 50, 24 pigs in each treatment group were treated orally with 43 mg of dichlorvos/kg of body weight, 3 X 3 mg of fenbendazole/kg, or 300 micrograms of ivermectin/kg, SC. Twenty-four pigs were not treated. On posttreatment day 7 (PID 57), 12 pigs from each treatment group (phase I) were slaughtered, and the anthelmintic efficacy of each treatment was determined. Efficacies against A suum, T suis, and O dentatum, respectively, were: dichlorvos, 100%, 99.9%, and 100%; fenbendazole, 100%, 99.8%, and 100%; and ivermectin, 98.7%, 53.9%, and 87.6%. Weight gains and feed conversions of the remaining pigs were monitored until they reached market weight (phase II). The average weight gains (kg) and feed conversions (kg of feed/kg of gain) at posttreatment day 81 (PID 131), respectively, were: 73.6 and 3.44 for nontreated controls, 78.9 and 3.31 for dichlorvos-treated pigs, 72.1 and 3.36 for fenbendazole-treated pigs, and 74 and 3.48 for ivermectin-treated pigs. Differences in average weight gains and feed conversions were not significant (P greater than 0.05).     

The influence of stocking rate on transmission of helminth parasites in pigs on permanent pasture during two consecutive summers

This study was made to elucidate the transmission of nematode infections in outdoor pigs at different stocking rates during two consecutive seasons. Five pigs (Group 1A) inoculated with low doses of Oesophagostomum dentatum, Ascaris suum, and Trichuris suis and five helminth-na?ve pigs (Group 1B) were turned out together in June 1996 on each of four pastures at stocking rates of 100, 240 (two pastures) and 576m(2) per pig, respectively. The pigs were slaughtered in early October, and pasture infectivity was subsequently measured using helminth-na?ve tracer pigs (Tracer). In 1997, 10 helminth-na?ve pigs were turned out on each pasture in May (Group 2) and again in August (Group 3), and allowed to graze for 12 weeks. The percentage of grass cover was reduced considerably at the high stocking rate in comparison to the other stocking rates. Transmission of all three helminths was observed on all pastures. In 1996, the O. dentatum faecal egg counts and worm burdens were significantly higher in pigs at the high stocking rate compared to pigs at the other stocking rates. O. dentatum did not survive the winter and pigs of Group 2 were inoculated with 3000 larvae each to reintroduce this parasite. Ascaris suum ELISA values and worm counts were highest at the high stocking rate in 1997 (Group 3). Transmission of T. suis was not significantly influenced by stocking rate. The results indicate that transmission of O. dentatum, and to some extent A. suum is influenced by stocking rate. However, both A. suum and T. suis eggs are still expected to constitute a high risk of infection on intensively used pastures where eggs may accumulate for years. The relationship between host density and helminth transmission seems more complex for grazing/rooting pigs than for grazing ruminants. This may be due to the differences in behaviour of the animals and the resulting differences in microclimate of the developing eggs/larvae.     

Some aspects of nematode infection in pigs from small herds

Two traditionally maintained, small herds from southern Poland, with 8 and 12 sows, respectively, were surveyed coprologically during 2006-2007. In one of the herds, while deworming a group of sows with levamisole, faecal samples were collected on Day -7, Day 0 (the day of treatment) and Day 10, in order to assess the therapeutic effect of the drug. Coprological investigation was performed also in 26 fatteners originating from other small farms and slaughtered in a local abattoir, with their intestines washed through for the presence of roundworms. In both herds examined, Ascaris suum and Oesophagostomum spp. were prevalent, whilst Trichuris suis appeared only very rarely. Mainly fatteners, replacement gilts and young sows were highly infected with A. suum. The roundworm occurrence in 2- 3-week-old piglets, with the intensity of 300 eggs per gram of faeces (EPG), indicated the possibility of parasite transmission to offspring very early in age. The highest level of Oesophagostomum spp. infection was observed in sows, but weaners were also much affected. For the group of dewormed sows, the mean faecal egg count reduction (FECR) was estimated to be 77.1- 80.4%, suggesting the presence of resistant nodular worms. A very high false-positive A. suum egg counts found in slaughtered animals (240 to 320 EPG) testified to a high contamination level of the environment of small piggeries, as well. Since the reciprocal transmission of parasites between pigs and poultry might occur, it implies that the flocks should be raised separately.