微量多拉菌素与伊维菌素对牦牛皮蝇幼虫驱除效力的研究

应用多拉菌素注射剂和伊维菌素浇泼剂微量给药,对自然感染皮蝇幼虫的犊牦牛进行驱虫效力研究。结果:给药后28~34d剖检和翌年3、5月份两次摸背检查远期防治效果,多拉菌素注射剂5μg/kg剂量组驱净率分别为85.0%和92.1%,驱虫率分别为93.6%、93.7%;10、20μg/kg剂量组均为100.0%。伊维菌素浇泼剂12.5μg/kg。剂量组驱净率分别为85.0%和91.2%,驱虫率分别为93.3%和93.2%;25、50μg/kg剂量组均为100.0%。对照组牦牛皮蝇1期幼虫感染率85.0%,平均感染强度29.7条;背部皮下瘤疱和皮肤虫孔的平均感染率84.1%,瘤疱和虫孔总数205个。试验证明供试两种药物使用微量驱除牦牛皮蝇1期幼虫高效安全经济,多拉菌素的最佳剂量为10μg/kg,伊维菌素的最佳剂量为25μg/kg。     

埃谱利诺菌素注射剂微量施药驱除牦牛皮蝇幼虫的效力试验

应用埃谱利诺菌素注射剂微量给药技术,对自然感染皮蝇幼虫的犊牦牛进行驱虫效力研究。结果:给药后28~35d剖检,对照组牦牛皮蝇1期幼虫感染率65%,平均感染强度28.92条(12~39)条;埃谱利诺菌素注射剂2μg/kg.bw剂量组驱净率和驱虫率分别为85%、94.95%,5、10、20μg/kg剂量组驱净率和驱虫率均达100%;给药后分别于翌年3月中旬和5月下旬两次触摸检查远期防治效果,对照组牦牛背部皮下瘤疱和皮肤虫孔平均感染率61.67%,瘤疱和虫孔均数5.91(4~13)个;埃谱利诺菌素注射剂2μg/kg剂量组平均驱净率、驱虫率分别为90.0%和92.7%,5、10、20μg/kg剂量组平均驱净率和驱虫率均达100%。试验证明埃谱利诺菌素注射剂微量注射对牦牛皮蝇幼虫均达高效,其中使用5μg/kg.bw埃谱利诺菌素注射剂为最佳剂量。     

牦牛皮蝇蛆病低残留防治技术研究

应用埃普利诺菌素注射剂采用常规与微量给药技术,进行对牦牛皮蝇蛆病的防治试验,10月下旬给药,翌年3、5月份两次触摸检查牛背部皮下瘤疱和皮肤虫孔,并设阳性对照组,评价两种给药技术对牦牛皮蝇蛆病的防治效果。结果:两次检查阳性对照组平均感染率为39.15%,平均感染强度6.75(1~17)个;埃普利诺菌素注射剂常规剂量100、200、300μg/kg试验组牦牛两次检查平均治愈率和驱虫率均达100.0%;埃普利诺菌素注射剂微量10、20、30μg/kg防治组平均治愈率分别为86.3%、94.2%和100.0%,驱虫率分别为79.7%、93.2和100.0%。使用安全。给泌乳牦牛皮下注射埃普利诺菌素注射液0.2mg/kg后54.00h,牛奶中的埃普利诺菌素浓度达到峰值7.38±2.61ng/m L,低于美国(12 ng/m L)和欧盟(20ng/m L)规定的埃普利诺菌素在牛奶中的最高残留限量标准,不需休药期;皮下注射0.4mg/kg后56.00±26.31h,牛奶中的皮下注射浓度达到峰值6.98±2.98ng/m L,低于欧盟规定(20ng/m L),不需休药期,高于美国规定(12ng/m L),需休药期。适合当前家畜健康养殖中对牦牛寄生虫病防治的需要。     

伊维菌素2种剂型对牦牛皮蝇蛆病的规模防治示范效果观察

为观察伊维菌素浇泼剂、注射剂对牦牛皮蝇蛆病的防治示范效果,选择放牧饲养的牦牛,伊维菌素浇泼剂按0.5mg/kg体重剂量沿背中线浇泼给药,伊维菌素注射剂按0.2mg/kg体重剂量颈部皮下注射给药,同时留未防治的对照群,分别在3、5月份采用触摸法抽样进行防治效果检查。结果:伊维菌素浇泼剂防治示范组牦牛2次检查的皮蝇蛆感染率在1.61%~3.23%之间,平均感染率2.42%,查出瘤疱和皮肤虫孔总数7个,平均感染强度1.75个,感染范围0~2个。2次检查未防治的对照组牦牛皮蝇蛆感染率在33.33%~38.89%之间,平均感染率为36.11%,查出瘤疱和皮肤虫孔总数152个,平均感染强度4.22个,感染范围0~14个。结果表明:伊维菌素浇泼剂防治示范组牦牛皮蝇蛆病治愈率为98.39%,驱虫率99.08%~99.54%,平均驱虫率99.31%;伊维菌素注射剂防治示范组牦牛皮蝇蛆病治愈率在98.39%~100.0%之间,平均治愈率为99.20%,驱虫率98.62%~100.0%,平均驱虫率99.31%。2种剂型的推荐剂量均达到了高效安全,可在高寒牧区牦牛皮蝇蛆病防治中推广应用。     

牦牛主要寄生虫病高效低残留防治技术研究(上)

本研究评价了埃普利诺菌素注射剂、浇泼剂对牦牛主要寄生虫病的驱虫疗效,为建立牦牛主要寄生虫病高效低残留防治技术提供依据。选用自然感染线虫、牛颚虱和皮蝇蛆的牦牛,采用粪检法和剖检法进行驱虫疗效试验。结果:埃普利诺菌素注射剂0. 1,0. 2,0. 3mg/kg剂量组消化道线虫虫卵转阴率分别为85. 0%,95. 0%和100. 0%,减少率分别为91. 9%,98. 4%和100. 0%。0. 2,0. 3mg/kg剂量组对牦牛网尾线虫L1转阴率和减少率均达100. 0%。0. 1mg/kg剂量组L1转阴率和减少率分别为90. 0%和95. 2%。0. 2,0. 3mg/kg剂量组原圆线虫L1转阴率分别为93. 3%,100. 0%,减少率分别为98. 3%,100. 0%。0. 1mg/kg剂量组L1转阴率和减少率分别为80. 0%,88. 5%。3个试验组对线虫成虫的总计驱虫率分别为90. 5%,97. 2%和99. 5%。埃普利诺菌素注射剂0. 3mg/kg剂量组给药后3d牛颚虱大部分死亡干瘪,第7d全部死亡干瘪,驱虫率均达100. 0%。0. 1mg/kg剂量组低剂量组的杀虫效果次于上述剂量。0. 2mg/kg剂量组与IVM注射剂0. 2mg/kg体重剂量组驱虫效果无显著差异。3个剂量组对牦牛皮蝇蛆的驱净率、驱虫率均达100. 0%;埃普利诺菌素浇泼剂0. 4mg/kg剂量组对牦牛消化道线虫的虫卵转阴率、减少率分别为95. 0%和96. 4%～98. 3%。对牛颚虱和皮蝇蛆的驱杀效率均为100%。0. 5mg/kg剂量组对牦牛消化道线虫的虫卵转阴率、减少率均达100. 0%,对牛颚虱和皮蝇蛆的杀虫效果均达100%,对牛颚虱与牦牛体内消化道线虫持效期至少为28d。研究结果表明,埃普利诺菌素注射剂、浇泼剂对牦牛线虫病、牛颚虱与牛皮蝇蛆病等主要寄生虫病的驱虫疗效高,有很好的控制效果。     

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。     

伊维菌素4种剂型不同给药方法对牦牛皮蝇蛆病防治的比较研究

选用伊维菌素浇泼剂、注射剂、片剂、干混悬剂4种剂型,分别按0.5,0.2,0.3,0.3mg/kg体重剂量,对1.5岁牦牛在10月中旬给药,进行不同给药方法用于防治牦牛皮蝇蛆病的给药速度、劳动强度、使用的安全性、防治效果等方面的比较研究。结果:给药速度以浇泼剂最佳,其次为注射剂,再次为干混悬剂,片剂最慢;劳动强度以浇泼剂最佳,其次为注射剂与干混悬剂,再次为片剂;伊维菌素注射剂、浇泼剂和干混悬剂的防治效果佳,其驱净率和驱虫率均达100.00%,片剂较低,平均驱净率和驱虫率分别为95.41%和96.36%;同期检查阳性对照组牦牛皮蝇蛆平均感染率33.33%、平均感染强度7.5个虫体。试验表明,伊维菌素4种剂型防治牦牛皮蝇蛆病高效安全,其中浇泼剂优势明显。     

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。     

埃谱利诺菌素浇泼剂对绵羊消化道线虫的驱虫效果评价5-6

为评价埃谱利诺菌素浇泼剂对绵羊消化道线虫驱虫效力,选择1.5岁自然感染消化道线虫的绵羊100只,随机分为5组,每组20只,1～3组为埃谱利诺菌素浇泼剂0.4、0.5和0.6mg/kg.b w组,沿背部皮肤中线浇注给药,4组为埃谱利诺菌素注射剂药物对照组,按0.2mg/kg剂量颈部皮下注射,5组为阳性对照组,不给药;采用粪便虫卵检查法评价驱虫效果。结果:给药后7、14d检查,0.5mg/kg剂量对消化道线虫虫卵转阴率分别为90.0%、95.0%,减少率分别为97.0%和99.3%; 0.6mg/kg剂量给药后7、14d检查,对消化道线虫虫卵转阴率、减少率均达100.0%; 0.4mg/kg剂量对消化道线虫虫卵的转阴率、减少率均低于0.5、0.6mg/kg剂量组。对照药物埃谱利诺菌素注射剂0.2mg/kg剂量组对消化道线虫的驱虫效果略高于埃谱利诺菌素浇泼剂0.5mg/kg剂量组;埃谱利诺菌浇泼剂3个剂量组试验绵羊未见异常反应。试验证明埃谱利诺菌浇泼剂0.4、0.5、0.6mg/kg体重剂量驱除绵羊消化道线虫安全有效,其中0.5、0.6mg/kg剂量高效安全低残留,推荐剂量以0.5mg/kg为宜。     

依普菌素搽背剂对牦牛皮蝇蛆的驱虫效果及安全性试验

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剂型,选取120头1.5岁牦牛,分为3组,试验1组(50头)用依普菌素搽背剂按0.5mg/kg体重剂量经背部皮肤浇泼给药,试验2组(50头)用伊维菌素注射剂按0.2mg/kg体重剂量经皮下注射给药,试验3组为对照组。翌年5月底对全部试验牛进行牛皮蝇蛆驱除效果检查。结果:两试验组牦牛皮蝇蛆病治愈率均为98%,而对照组的感染率为100%,平均感染强度为10.9(2~21)。依普菌素搽背剂对牦牛皮蝇幼虫的驱虫率达99.54%。表明依普菌素搽背剂0.5mg/kg剂量安全,驱虫方法简单,可用于高寒牧区牦牛寄生虫病驱治。     

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。     

Field efficacy of minidosed eprinomectin against Hypoderma spp. in dairy cattle

A chemoprophylactic field trial was conducted to assess the efficacy of pour-on eprinomectin applied at the approximate dose of 50 mcg/kg to dairy cattle with naturally occurring hypodermosis. Two-hundred-eleven cattle, selected from two herds with a high prevalence of Hypoderma spp. infestation, were divided in three groups: Group A (N = 71) was treated with pour-on eprinomectin at the recommended dosage of 500 mcg/kg, Group B (N = 64) at the lower dose of 50 mcg/kg, a third group (Group C, N = 76) served as untreated control group. Treatments were performed in November-December 2002 and the animals were examined for the presence of warbles in the following April and June. No larvae emerged in the treated groups, whereas a variable number of warbles (ranging from 1 to 28) were found in control animals. Adverse reactions were not observed in any animal, and only minor side effects were observed. A larger field trial carried out in the following year (1064 treated and 131 untreated control cattle) confirmed the chemoprophylactic efficacy of minidosed eprinomectin against Hypoderma spp. Administration of eprinomectin minidoses in dairy cattle is interesting because of the low costs involved and no need for milk withdrawal.     

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%。     

The efficacy of eprinomectin extended-release injection against Hypoderma spp. (Diptera: Oestridae) in cattle

The efficacy of eprinomectin in an extended-release injection (ERI) formulation was determined in cattle harboring naturally acquired infestations of first- or second- and third-stage larvae of Hypoderma spp. in three studies conducted according to the same protocol in the USA (two studies) and Germany (one study). Thirty cattle sourced from herds with a history of Hypoderma infestation were included in each study. Cattle were formed into replicates of three animals each on the basis of pre-treatment anti-Hypoderma antibody titers. Within replicates each animal was randomly allocated to one of the following treatments: ERI vehicle (control) at 1 mL/50 kg bodyweight, administered once on Day 0; Eprinomectin 5% ERI at 1 mL/50 kg bodyweight (1.0 mg eprinomectin/kg), administered once on Day 0 (when larvae were expected to be first instars); or Eprinomectin 5% ERI at 1 mL/50 kg bodyweight (1.0 mg eprinomectin/kg), administered once when larvae were second or third instars (study dependent, Day 73, 119, or 140). Treatments were administered by subcutaneous injection in front of the shoulder. In all studies, emerging and/or expressed Hypoderma larvae were recovered, speciated, and counted and viability was determined. Eprinomectin LAI treatment was 100% (p < 0.05) efficacious against first- and second- or third-stage larvae of Hypoderma bovis (two studies) and Hypoderma lineatum (one study). All animals accepted the treatment well. No adverse reaction to treatments was observed in any animal in any study.     

乙酰氨基阿维菌素乳剂HPLC含量检测方法的建立

[目的]建立高效液相色谱法测定乙酰氨基阿维菌素乳剂含量的方法。[方法]采用C18（150×4．6mm,5μm）色谱柱,以乙腈-水（70：30）为流动相,流速为1．0mL/min,检测波长为245nm,进样量为20μL,柱温为25℃。[结果]乙酰氨基阿维菌素在0．1～20μg/mL浓度范围内呈现良好的线性关系,标准曲线方程为C=1．6015A-0．00206,r=1．000（n=5）,该方法的RSD在0．72％～1．40％,平均回收率在96．5％～100．5％。[结论]该方法灵敏度高、准确度高、重现性好、简便快速,可用于乙酰氨基阿维菌素乳剂和其他剂型的质量控制。     

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。     

Failure of ivermectin and eprinomectin to control Amblyomma parvum in goats: characterization of acaricidal activity and drug pharmacokinetic disposition

The therapeutic efficacies of ivermectin (subcutaneous injection) and eprinomectin (topical treatment) given at two different dosage levels to goats naturally infested with Amblyomma parvum were assessed. Treatments included subcutaneous injection of ivermectin at 0.2 and 0.4mg/kg and extra-label pour-on administration of eprinomectin at 0.5 and 1mg/kgb.w. Ivermectin and eprinomectin failed to control Amblyomma parvum on goats. Treatment with ivermectin resulted in a low number of engorged female ticks in relation to untreated control goats and, at the highest dose rate (0.4mg/kg), the female engorgement weights were significantly lower and the pre-oviposition period significantly longer than those observed in ticks recovered from untreated control goats. The tick efficacy assessment was complemented in a separate group of tick-free goats with a pharmacokinetic characterization of eprinomectin (topically administered at 0.5, 1.0 and 1.5mg/kg) and ivermectin (subcutaneous treatment given at (0.2 and 0.4mg/kg) in goats. Heparinized blood samples were taken between 0 and 21 days post-treatment. Higher and more persistent drug plasma concentrations were recovered after the subcutaneous treatment with ivermectin compared to those obtained for eprinomectin topically administered. The understanding of the relationship among the pattern of drug absorption, the kinetic disposition and the resultant clinical efficacy is relevant to improve the poor performance observed for ivermectin and eprinomectin against A. parvum on goats.     

Efficacy of different dosages of ivermectin injectable against the Hypoderma spp. in yaks

A chemotherapy trial was conducted to determine the lowest dosage of injectable preparation of ivermectin against Hypoderma spp. infestation in yaks in Tibetan areas in Tianzhu county, Gansu province, in northwest of China. One hundred and sixty yaks were randomly divided into four groups of 40 yaks for the trial. The first three groups were treated by subcutaneous injection in the neck with 0.1% ivermectin (respectively, 1, 5, 10 microg/kg body weight). The fourth group was not treated and considered as control group. All the experiments were performed in November 2000 and the animals were examined for the presence of warbles in the next March and May. The results indicated that there was no warbles found on the back of treated animal while third stage larvae were palpated on back of some of the yaks in control group. It is concluded that dosage of 1 microg/kg ivermectin injectable was sufficient to kill or stop development of larvae of Hypoderma spp. in naturally infected yaks if administrated in November.     

Plasma kinetics,excretion in milk of eprinomectin,and its efficacy against Hypoderma spp. following topical administration in yaks

The plasma pharmacokinetics and mammary excretion of eprinomectin were determined in dairy yaks following topical administration at a dose of 0.5 mg/kg. The kinetics of plasma and milk concentrations were analyzed using a noncompartmental model. Plasma and milk concentrations of eprinomectin increased to reach maximal concentrations of 5.45 ± 2.84 and 2.29 ± 0.90 ng/mL at a T_max of 1.79 ± 0.57 and 2.00 ± 0.82 days, respectively. The concentration of eprinomectin in plasma was remained >0.5 ng/mL for more than 30 days after administration. The mean residence times of eprinomectin in plasma and milk were 14.73 ± 6.22 and 9.37 ± 2.81 days, respectively. The AUC value in plasma (55.89 ± 18.16 ng day/mL) was threefold greater than that in milk (18.02 ± 6.48 ng day/mL). The AUC milk/plasma ratio was 0.33 ± 0.08. The systemic availability of eprinomectin in yaks was lower than that observed value in other domestic bovines. The low level of eprinomectin excretion in milk suggests that eprinomectin can be used in yaks with zero milk‐withdrawal time. The efficacy of eprinomectin against naturally acquired larvae of Hypoderma spp. was also determined in yaks. Topically administrated eprinomectin at a dose of 0.5 mg/kg was 100% efficacious against larvae of Hypoderma bovis, H. lineatum, and H. sinense.