放牧绵羊主要寄生虫病药物防治技术试验与示范效果观察

为评价伊维菌素注射剂的驱虫效果与对放牧绵羊线虫病及外寄生虫病的防治示范效果,选择1.5岁感染线虫和部分外寄生虫的绵羊150只,设伊维菌素注射剂0.1,0.2和0.3mg/kg体重剂量组和伊维菌素片剂对照组,进行驱虫效果评价;在冬季应用伊维菌素注射剂按0.2mg/kg体重剂量对放牧绵羊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:药效试验中伊维菌素注射剂0.2mg/kg对绵羊消化道线虫虫卵转阴率和减少率分别为93.3%,99.3%,对原圆科线虫幼虫转阴率和减少率分别为90.0%和96.1%;0.3mg/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%;0.1mg/kg剂量对消化道线虫虫卵转阴率和减少率分别为76.7%,88.6%,原圆科线虫幼虫转阴率和减少率分别为66.7%和86.1%。防治示范群绵羊消化道线虫虫卵转阴率为93.3%,虫卵减少率为96.8%;对原圆科线虫幼虫转阴率和减少率分别为90.0%和96.2%。同期检查未防治对照组虫卵EPG和幼虫数略有增加。技术示范群比未示范群每只成年羊平均多增重5.47kg、幼年羊成活率平均提高2.1个百分点。结果表明该防治技术对放牧绵羊主要寄生虫病高效安全,效益显著。     

伊维菌素泼背剂对牦牛寄生虫的驱除效果试验

为选择适应于高寒牧区放牧牦牛大群驱除体内外寄生虫的理想荆型,在青海大通种牛场通过粪检选60头牦牛,随机分为3组,每组20头,试验1组用伊维菌素泼背荆接0.5 mg/kg体重剂量经背部皮肤浇泼给药,试验2组用伊维菌素注射剂按0.2 mg/kg体重剂量经皮下注射给药,试验3组为空白对照组.分析了三组不同寄生虫卵转率、虫卵减少率及驱虫率指标的变化,同时对药物的安全性进行了观察.结果试验1组消化道线虫虫卵转阴率、减少率分别为90%和99.1%,原圆科线虫幼虫转阴率、减少率分别为80%和92.8%;线虫成虫、寄生阶段幼虫的总计驱虫率分别为99.3%和98.8%;试验2组相应指标分别为90%和98.7%、80%和92.9%、99.4%和99.2%;1.2组对牛颚虱杀虫率均达100%,但对莫尼茨绦虫无效,对照组体内外寄生虫均无明显变化.表明伊维菌素泼背剂0.5 mg/kg剂量安全,驱虫效果可信,可在青海高寒地区牦牛体内外寄生虫驱虫工作中推广应用.     

伊维菌素和左旋咪唑驱除山羊消化道线虫和体外寄生虫的效果比较

用饱和盐水浮聚法对60只云岭峻王黑山羊筛选肠道线虫感染者,共发现8种消化道线虫,分别是捻转血矛线虫、奥斯特线虫、古柏线虫、马歇尔线虫、仰口线虫、毛圆线虫、食道口线虫、夏伯特线虫,它们的感染率分别为100%、100%、100%、71.67%、86.67%、22.33%、100%、90%;体外寄生虫有软蜱和疥螨,感染率为100%和85%.从中选30只感染寄生虫的阳性山羊,分别用左旋咪唑片剂和伊维菌素注射液进行驱虫试验,间隔7 d重复用药一次.结果表明:左旋咪唑组消化道线虫的虫卵减少率平均为84.63%,对体外寄生虫无效;伊维菌素组消化道线虫的虫卵减少率平均为99%,体外寄生虫软蜱的感染率下降为13.33%,疥螨的感染率下降为3.33%;在增重上,左旋咪唑组平均日增重为48.89 g,伊维菌素组平均日增重为72.22 g,比左旋咪唑组提高47.72%;即伊维菌素注射液驱虫效果明显优于左旋咪唑片剂驱虫效果.     

埃谱利诺菌素注射剂对藏羊线虫与寄生期幼虫的驱虫效果

应用埃谱利诺菌素注射剂,选择自然感染线虫的1岁藏系绵羊150只,分别按0.1、0.2、0.3 mg/kg体重剂量皮下注射给药,驱除藏羊线虫,同时设伊维菌素注射剂药物对照组和阳性对照组。结果显示:①埃谱利诺菌素注射剂0.2、0.3 mg/kg体重剂量对藏羊消化道线虫虫卵转阴率分别为93.3%和100.0%,减少率分别为99.18%和100.0%;对网尾线虫幼虫转阴率和减少率均达100.0%,原圆科线虫幼虫转阴率分别为90.0%、100.0%,减少率分别为95.79%和100.0%;对线虫成虫的总计驱虫率分别为98.83%和99.96%,对线虫寄生阶段幼虫的总计驱虫率分别为96.42%和99.17%。②0.1 mg/kg剂量对线虫虫卵(幼虫)的转阴率、减少率、驱虫率均次于0.2、0.3 mg/kg体重剂量组。③对照药物伊维菌素注射剂0.2 mg/kg体重剂量对消化道线虫、原圆科线虫幼虫转阴率和减少率、对线虫成虫及其寄生阶段幼虫的总计驱虫率与同剂量埃谱利诺菌素注射剂基本一致。④藏羊皮下注射试验剂量未出现任何异常反应。试验证明埃谱利诺菌素注射剂0.2 mg/kg体重剂量驱除线虫高效安全。     

爱普利注射剂对放牧绵羊体内外寄生虫的驱虫试验

应用爱普利注射剂,选择自然感染线虫和体外寄生虫的1.5岁放牧藏系绵羊100只,分别按0.1、0.2、0.3 mg/kg.b w剂量皮下注射给药,同时设伊维菌素注射剂药物对照组和阳性对照组,评价驱除放牧绵羊体内线虫与体外寄生虫的效果。结果显示:爱普利注射剂0.2、0.3 mg/kg剂量对放牧绵羊消化道线虫虫卵转阴率分别为95.0%和100.0%,减少率分别为98.4%和100.0%;网尾线虫幼虫转阴率和减少率均达100.0%,原圆科线虫幼虫转阴率分别为90.0%和100.0%,减少率分别为96.1%和100.0%;对主要线虫虫卵(幼虫)的平均有效率分别达98.0%和100.0%;第7d对绵羊颚虱、足颚虱的转阴率、杀虫率均达100%;对羊蜱蝇的转阴率分别为90.0%和100.0%,杀虫率分别达92.3%和100%;均达到了高效。爱普利注射剂0.1 mg/kg剂量对线虫虫卵(幼虫)的转阴率、减少率及对体外寄生虫的杀虫率均次于0.2、0.3 mg/kg剂量组。对照药物伊维菌素注射剂0.2 mg/kg剂量消化道线虫虫卵转阴率、减少率分别为95.0%和97.8%;网尾线虫幼虫转阴率和减少率均达100.0%,原圆科线虫幼虫转阴率、减少率分别为85.0%和94.3%;第7d绵羊颚虱、足颚虱的转阴率、杀虫率均达100%;羊蜱蝇转阴率、杀虫率分别为80.0%和90%。阳性对照组线虫虫卵(幼虫)与给药前无明显变化、3种体外寄生虫感染情况较给药前略有增加。绵羊皮下注射3个剂量爱普利注射剂,未出现任何异常反应。试验证明爱普利注射剂3个剂量对藏系绵羊线虫虫卵(幼虫)、3种体外寄生虫均有效,其中0.2 mg/kg剂量驱除放牧绵羊线虫高效安全经济。     

不同驱虫药物对奶山羊消化道线虫驱虫效果研究

本研究旨在观察不同驱虫药物对奶山羊消化道线虫的驱虫效果,为今后寄生虫病的防治筛选更好的驱虫药物。选取奶山羊96只,分3组,每组32只,分别投喂伊维菌素注射液、芬苯达唑粉和伊维菌素芬苯达唑预混剂3种驱虫药物,采用饱和盐水漂浮法和麦克马斯特法检测驱虫前后线虫的感染情况。结果发现:伊维菌素注射液组虫卵转阴率为6.25%;芬苯达唑粉剂组虫卵转阴率为31.25%;伊维菌素芬苯达唑预混剂组虫卵转阴率为50.00%。驱虫前后感染强度伊维菌素注射液组差异显著(P<0.05),芬苯达唑粉剂组差异极显著(P<0.01),伊维菌素芬苯达唑预混剂组差异极显著(P<0.01)。因此,建议采用伊维菌素芬苯达唑预混剂作为奶山羊消化道线虫首选驱虫药物。     

拜宠清和伊维菌素对自然感染犬弓首蛔虫临床药效比较

用伊维菌素和拜宠清分别对自然感染犬弓首蛔虫(Toxocara canis)的犬进行驱虫,以虫卵减少率和虫卵转阴率为指标判定驱虫效果,比较2种药物对犬蛔虫的驱虫效力。结果显示:从虫卵减少率和虫卵转阴率来看,第1次给药后第5、10、15天拜宠清组和伊维菌素组的虫卵减少率均超过95%,但在第1次驱虫15 d后的虫卵转阴率均不能达到100%。在第1次驱虫后2周进行第2次驱虫,驱虫后5～10 d虫卵转阴率均能达到100%。从排虫情况来看,伊维菌素组多在给药后6～8 d排虫,拜宠清组多在给药后2～4 d排虫。从剖检情况看,经两次驱虫,驱净率均能到达100%。研究表明,伊维菌素和拜宠清对犬弓首蛔虫均有很好的驱虫效果。     

3种驱虫药对陕北白绒山羊消化道线虫的驱虫效果比较

为了更好地了解常用驱虫药的驱虫效果,选择陕北白绒山羊开展驱虫研究。试验选取3种市场常用驱虫药(伊维菌素注射液、芬苯达唑粉、伊维菌素芬苯达唑预混剂),应用饱和食盐水漂浮法和虫卵计数法对陕北白绒山羊的消化道线虫驱虫前后的感染情况进行检测。结果表明,伊维菌素注射液组驱虫后虫卵转阴率为6.25%,感染强度由766.7降低至233.3;芬苯达唑组驱虫后虫卵转阴率为31.25%,感染强度由766.7降低至100;伊维菌素芬苯达唑预混剂组驱虫后虫卵转阴率为50%,感染强度由766.7降低至167.0。建议在陕北白绒山羊生产中将伊维菌素芬苯达唑预混剂作为消化道线虫的首选驱虫药。     

两种药物驱除放牧绵羊线虫的效果对比试验

选用伊维菌素注射剂按0.1,0.2,0.3mg/kg剂量和盐酸左旋咪唑片剂7.5,15,22.5mg/kg剂量对放牧绵羊进行驱虫试验,分别于给药后7d、14d检查效果。结果：伊维菌素组第7d消化道线虫的虫卵减少率分别为99.10%,99.18%和99.21%。14d分别为97.18%,98.91%,99.21%;肺线虫幼虫7d无明显变化,14d减少率分别为96.59%,96.51%,97.37%。左旋咪唑组第7d消化道线虫的虫卵减少率分别为67.79%,93.17%和95.52%,14d分别为54.68%,83.62%,84.30%;对肺线虫第7d幼虫减少率分别为62.76%,58.13%和45.74%,14d分别为0、72.76%,83.72%。试验表明伊维菌素注射液驱虫效果明显优于左旋咪唑片剂。     

国产伊维菌素粉剂对宁夏滩羊消化道线虫的驱虫试验

使用国产伊维菌素粉剂和进口害获灭注射剂对宁夏滩羊消化道线虫作对比驱虫试验，结果表明：随着国产伊维菌素剂量的增加，虫卵转阴率和虫卵减少率比进口害获灭组的虫卵转阴率和虫卵减少率均高。两者对宁夏滩羊消化道线虫均有极显著的驱虫作用，说明国产伊维菌一纱可替代进口害获灭。     

伊维菌素干混悬剂驱除猪蛔虫效果与安全性试验

应用伊维菌素干混悬剂进行了驱除猪蛔虫的效力及安全性试验。结果：0．3mg/kg b.w剂量对猪蛔虫的虫卵转阴率、虫卵减少率和驱虫率均达100％，猪可耐受1．5mg/kg剂量。试验证明伊维菌素干混悬剂驱除猪蛔虫安全高效，投药方便，成本较低，具有推广前景。     

高原牛羊胃肠道线虫驱治模式研究

根据高原地区＂春乏＂期间,牛、羊因胃肠道线虫病引起死亡严重的突出情况,自列项目,在全州范围划为三大区域,以项目区为中心,在牛、羊发病率和死亡率相对高的乡（镇）、村设点,将93330头（只）牛、羊分为三个组,作为高原地区牛、羊胃肠道线虫病防治技术模块,结果3个试验组用药前胃肠道寄生虫感染率均为100%,早晨在放牧前投喂赛爱吉夏结、克虫特和丙硫苯咪唑等药物后,7 d粪检EPG,虫卵转阴率和虫卵减少数均为100%。间隔7 d重复驱虫1次,防治效果显著。有计划的用驱虫药丙硫咪唑,克虫特、伊维菌素。在每年春季2~3月,秋季8~9月份进行两次驱虫。可提高牛、羊有机体的免疫力,降低牛、羊胃肠道线虫病的发病率和死亡率,减轻对养殖业的危害。     

Effect of parasitism with Nematodirus battus on the pharmacokinetics of levamisole, ivermectin and netobimin

The pharmacokinetics of levamisole, ivermectin and netobimin administered orally and by subcutaneous injection were compared in lambs exposed to a moderate challenge with Nematodirus battus and in parasite naive lambs. There were no significant differences (P greater than 0.05) in the bioavailability of any of the anthelmintics tested between parasitized and non-parasitized animals. Levamisole reduced nematode faecal egg output by more than 99% when administered by either route. Ivermectin was also highly effective (greater than 99%). Orally administered netobimin reduced egg output by more than 98% seven days after administration. However egg output was only reduced by 89% 21 days after administration, suggesting poor activity against the early parasitic stages of N. battus. Netobimin was not effective against N. battus when administered by the subcutaneous route and this was probably because very low plasma concentrations of its active albendazole metabolites were achieved.     

多拉菌素等三种药物驱除绵羊胃肠道线虫效果观察

通过选取多拉菌素等三种驱虫药物对绵羊胃肠道线虫进行驱除。结果表明,三种药物对绵羊胃肠道线虫均有明显效果,平均驱虫率依次为多拉菌素组（98.7%）〉伊维菌素组（94.3%）〉丙硫苯咪唑组（82%）。比较后确定适合我市推广的新型驱虫药物为多拉菌素注射液。     

Efficacy of abamectin against ivermectin-resistant strain of Trichostrongylus colubriformis in sheep

The efficacy of two formulations of abamectin, i.e. oral and injectable was determined against ivermectin-resistant strain of T. colubriformis in sheep. Twenty-four lambs were infected with 10,000 third stage larvae of ivermectin-resistant strain of T. colubriformis. Twenty-four days post-infection, the lambs were divided randomly into four groups of six animals each according to egg counts. The first group was left untreated and kept as a control. The second group was treated with ivermectin (oral) at 0.2mg kg(-1) body weight. The third group was treated with oral formulation of abamectin at 0.2mg kg(-1) body weight. The fourth group was treated with injectable formulation of abamectin at 0.2mg kg(-1) body weight. Fecal egg count and controlled slaughter tests were employed to determine the efficacy of abamectin (oral and injection) against ivermectin-resistant strain of T. colubriformis in sheep. Reduction in arithmetic mean fecal egg counts achieved by ivermectin (oral), abamectin (oral) and abamectin (injection) was 66, 98 and 76%, respectively 10 days after treatment. Ivermectin (oral), abamectin (oral) and abamectin (injection) reduced arithmetic mean worm burden by 63, 97 and 74%, respectively. The findings demonstrated that abamectin oral formulation was more effective than abamectin injection against ivermectin-resistant strain of T. colubriformis in sheep.     

Comparative cost-effectiveness of ivermectin versus topical organophosphate in feedlot yearlings

A replicated-pen field trial was performed under commercial feedlot conditions in western Canada to determine the cost-effectiveness of administering ivermectin to yearling beef cattle upon entry to the feedlot after the grazing season, and to establish the level of trichostrongylid gastrointestinal parasite infection in this population, as estimated by fecal egg counts. Six thousand eight hundred and eighty-three, mixed breed, yearling steers were randomly allocated upon arrival at the feedlot to one of 2 experimental groups as follows: Ivermectin, which received topical ivermectin (0.5%) at the rate of 1.0 mL/10 kg body weight; or Fenthion, which received topical fenthion (20%) at the rate of 12 mL/295 kg body weight. There were 15 pens in each experimental group. Final weight, weight gain, average daily gain, and dry matter intake to gain ratio were significantly (P < 0.05) improved in the Ivermectin group as compared with the Fenthion group. There were no significant (P > or = 0.05) differences in initial weight, days on feed, or daily dry matter intake between the experimental groups. The geometric mean fecal egg counts at the time of allocation were 14.7 eggs/5 g and 16.6 eggs/5 g for the Ivermectin and Fenthion groups, respectively (P > or = 0.05). There were no significant (P > or = 0.05) differences in morbidity or mortality between the experimental groups. In the economic analysis, the significant improvements in feedlot performance in the Ivermectin group resulted in a net economic advantage of $4.20 CDN per animal.     

The efficacy of ivermectin and levamisole against natural Nematodirus spathiger infection in the Arabian sand gazelle (Gazella subgutturosa marica) and the Arabian mountain gazelle (Gazella gazella) in Saudi Arabia

The efficacy of two broad spectrum anthelmintics (Ivermectin and Levamisole) against the nematode Nematodirus spathiger in the reem (Arabian sand gazelle) and idmi (Arabian mountain gazelle) at King Khalid Wildlife Research Centre (KKWRC) was determined. Gazelles of both species naturally infected with N. spathiger were each divided into 3 groups. One group was treated with Ivermectin, the other group with Levamisole and the last group was left as untreated control. Faecal egg counts were employed to determine the efficacy of the two drugs against N. spathiger infection in both gazelle species. Reduction in arithmetic mean faecal egg counts achieved by Ivermectin and Levamisole in the reem gazelles was 94% and 89.3%, respectively. The reduction in the idmi gazelles was 97.2% and 96.4%, respectively. Hence, both anthelmintics appeared to be more effective in the idmi gazelles than in the reem gazelles, however, there was no significant difference in the faecal egg reduction tests in both animal species.     

Evidence for multiple anthelmintic resistance in two nematode parasite genera on a Saanen goat dairy

Multiple resistance was demonstrated within the experimental milking goat herd at the Ruakura Agricultural Centre. The development of this resistance was probably exacerbated by the atypical animal management and parasite control programmes under which the dairy was managed. Resistance by Teladorsagia (Ostertagia) spp. to members of the three broad-spectrum families of anthelmintic is reported for the first time. Worm counts in a controlled slaughter trial demonstrated multiple anthelmintic resistance in a mixed population of Teladorsagia (T. circumcincta and T. trifurcata) and Trichostrongylus spp. The efficacies of oxfendazole, morantel citrate and ivermectin in reducing the Teladorsagia population were 43.8%, 75.6% and 93.1%, respectively. Ivermectin removed more than 99% of the small intestinal Trichostrongylus spp. but oxfendazole and morantel were less effective, removing 37.9% and 87.7%, respectively. Only treatment with ivermectin totally eliminated faecal nematode egg counts 8 days after treatment. The lack of agreement between faecal nematode egg depressions and worm counts in lambs given ivermectin suggests that the drug may have affected the fecundity of the surviving nematode population or the assay lacked the sensitivity required. These data suggest that the sole use of faecal egg depression would be inappropriate for accurate assessment of anthelmintic effectiveness.     

延胡索酸二钠对早期断奶羔羊生长性能、瘤胃发酵功能及胃肠道发育的影响

本研究旨在探讨饲粮中添加延胡索酸二钠对早期断奶羔羊生长性能、瘤胃发酵功能及胃肠道发育的影响。试验选用30只(50±5)日龄、体重为(25±2)kg的公羔,随机分为3组,每组10只。对照组饲喂基础饲粮,试验组在对照组的基础上添加0.5%和1.0%的延胡索酸二钠。试验期70 d。结果显示:1)饲粮添加延胡索酸二钠提高了平均日增重,其中1.0%组显著高于对照组(P0.05)。2)延胡索酸二钠未显著影响瘤胃液p H(P0.05),而显著降低了氨态氮浓度(P0.05);延胡索酸二钠极显著降低了瘤胃液乳酸浓度(P0.01);1.0%组瘤胃液总挥发性脂肪酸、乙酸和丙酸浓度显著高于对照组(P0.05)。3)试验组小肠绒毛高度均高于对照组,其中0.5%组羔羊的十二指肠、空肠、回肠的肠绒毛高度分别显著增加了30.3%、30.6%、46.1%(P0.05);试验组的十二指肠绒毛高度/隐窝深度显著大于对照组(P0.05),其中0.5%组的绒毛高度/隐窝深度较对照组增加了58.6%;0.5%和1.0%组羔羊的瘤胃壁乳头高度分别比对照组提高139.84和156.74μm(P0.05);试验组瘤胃壁乳头密度与对照组比较无显著差异(P0.05)。结果表明,添加延胡索酸二钠显著提高了羔羊的生长性能,促进了早期断奶羔羊瘤胃及肠道的发育。     

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.