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单一种细颈线虫感染羊只模型的建立 《畜牧与饲料科学》1995,16(1):36-36
将有细颈线虫（ＮｅｍａｔｏｄｉｒｕｓＳＰ．）混合感染的绵羊粪便用饱和盐水漂浮法收集混合虫卵,用２００目网筛分离纯化细颈线虫卵,在２６℃条件下培养３周后,获得细颈线虫感染性幼虫。给经过丙硫咪唑驱虫后的无虫羔羊一次口服１万条该幼虫,于感染后第１６天试验羊粪便检查到纯细颈线虫卵,４９天达到产卵高峰,ＥＰＧ＝２７５,在保持感染羊不受污染条件下,建立了单一种细颈线虫感染羊模型。 相似文献
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用人工感染捻转血矛线虫单一种试验羊粪便培养收集感染性幼虫。经０．０６％和０．０８％次氯酸钠脱鞘，脱鞘率可达９０％以上，慢速致冷后幼虫的存活率为６４．５％。加入冷冻保护剂不能提高冷冻感染性幼虫的存活率。用正常的感染性幼虫感染试验羊后第１７ｄ即可查到虫卵，剖杀后成虫的回收率为２．６％，而相同数量的冷冻保藏的感染性幼虫感染后第２１ｄ才查到虫卵，成虫回收率为０．８％。表明冷冻保藏后的感染性幼虫发育受阻，成 相似文献
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本实验用人工的方法培养了双管鲍杰线虫(Bourgelatia diducta Railliet,Henry andBauche,1919)的虫卵和幼虫。虫卵在培养液中孵化后,经第一、第二期幼虫,发育成为第三期幼虫,第三期幼虫具有感染性。说明双管鲍杰线虫的早期发育史,与其亲缘关系较近的同科其他线虫的早期发育史,有着相似的发育规律。 本实验在显微镜下,全面地观察了双管鲍杰线虫从虫卵至第三期幼虫在培养液中的发育情况,同时比较详细地描述了各期虫卵和幼虫的形态特征。 本实验还用人工培养的第三期幼虫经口作动物感染试验。感染后39～42天,幼虫在猪体内发育至性成熟,从而证实了双管鲍杰线虫的发育型为直接发育型。 相似文献
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《中国畜牧兽医》2020,(8)
为初步探讨苦楝对捻转血矛线虫的作用,本试验通过观察苦楝提取物对虫卵和幼虫活性及形态变化的影响,评估其对捻转血矛线虫的驱虫活性,以期为家畜捻转血矛线虫病的防控及植物驱虫药物的研发奠定基础。试验对苦楝水提取物和乙醇提取物设置5个浓度(25、12.5、6.25、3.125、1.562 mg/mL)进行虫卵孵化试验和幼虫活性试验,对不同浓度药物处理的虫卵及幼虫进行计数,并观察药物作用后虫卵和幼虫的孵化状态及形态变化。结果显示,正常孵育的虫卵和幼虫活力良好,苦楝提取物作用48 h后,虫卵呈未孵化、半孵化状态,发育至桑葚期、蝌蚪期及幼虫期死亡,并且各浓度苦楝水提物和醇提物对虫卵均具有抑制作用,其中苦楝皮醇提物对虫卵孵化的抑制效果最佳,在浓度25 mg/mL时,对虫卵孵化的抑制率高达98.2%,在12.5 mg/mL时,苦楝子醇提物对虫卵的抑制率极显著高于苦楝皮醇提取物(P0.01)。苦楝子提取物对感染性三期幼虫的致死效果较差,在50 mg/mL时对幼虫有较高致死率(82.6%)。苦楝皮水提取物在浓度为50 mg/mL时对幼虫的致死效果尤为突出,幼虫死亡率为97.0%,死亡的幼虫呈"直线型"或"弓型"。经方差分析,在12.5～50 mg/mL浓度范围内,相同浓度苦楝水提取物之间的致死率存在显著或极显著差异(P0.05;P0.01),同浓度苦楝醇提取物对幼虫的致死率存在极显著性差异(P0.01)。综上所述,苦楝提取物对体外的捻转血矛线虫卵和感染性三期幼虫的活性均有抑制作用,其中25 mg/mL苦楝皮醇提物对虫卵孵化的抑制效果最佳,50 mg/mL苦楝皮水提物对感染性三期幼虫的致死作用最好。 相似文献
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为初步探讨苦楝对捻转血矛线虫的作用,本试验通过观察苦楝提取物对虫卵和幼虫活性及形态变化的影响,评估其对捻转血矛线虫的驱虫活性,以期为家畜捻转血矛线虫病的防控及植物驱虫药物的研发奠定基础。试验对苦楝水提取物和乙醇提取物设置5个浓度（25、12.5、6.25、3.125、1.562 mg/mL）进行虫卵孵化试验和幼虫活性试验,对不同浓度药物处理的虫卵及幼虫进行计数,并观察药物作用后虫卵和幼虫的孵化状态及形态变化。结果显示,正常孵育的虫卵和幼虫活力良好,苦楝提取物作用48 h后,虫卵呈未孵化、半孵化状态,发育至桑葚期、蝌蚪期及幼虫期死亡,并且各浓度苦楝水提物和醇提物对虫卵均具有抑制作用,其中苦楝皮醇提物对虫卵孵化的抑制效果最佳,在浓度25 mg/mL时,对虫卵孵化的抑制率高达98.2%,在12.5 mg/mL时,苦楝子醇提物对虫卵的抑制率极显著高于苦楝皮醇提取物（P<0.01）。苦楝子提取物对感染性三期幼虫的致死效果较差,在50 mg/mL时对幼虫有较高致死率（82.6%）。苦楝皮水提取物在浓度为50 mg/mL时对幼虫的致死效果尤为突出,幼虫死亡率为97.0%,死亡的幼虫呈"直线型"或"弓型"。经方差分析,在12.5~50 mg/mL浓度范围内,相同浓度苦楝水提取物之间的致死率存在显著或极显著差异（P<0.05;P<0.01）,同浓度苦楝醇提取物对幼虫的致死率存在极显著性差异（P<0.01）。综上所述,苦楝提取物对体外的捻转血矛线虫卵和感染性三期幼虫的活性均有抑制作用,其中25 mg/mL苦楝皮醇提物对虫卵孵化的抑制效果最佳,50 mg/mL苦楝皮水提物对感染性三期幼虫的致死作用最好。 相似文献
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用Ｒｉｎｔａｌ片进行了驱除绵羊消化道线虫试验。结果表明当５ｍｇ／ｋｇ体重剂量时对捻转血矛线虫、哥伦比亚线虫、羊仰口线虫、细预属线虫和奥斯特线虫等绵羊消化道线虫的虫卵减少率，虫卵转阴率、虫卵孵化第三期幼虫减少率和第三期幼虫转阴率均可达到１００％，且安全，无任何毒副作用。 相似文献
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用Rintal颗粒剂对绵羊进行了消化道线虫驱虫试验。结果表明当前剂量为5.0mg/kg体重时，Rintal颗粒剂对绵羊食道口线虫、细颈属线虫、毛圆线虫、夏伯特线虫、奥斯特线虫以及肺丝虫等虫卵减少率，虫卵转阴率、虫卵孵化第3期幼虫减少率和第3期幼虫转阴率均为100%，而且安全，使用方便，易于保管运输。 相似文献
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Comparative susceptibility of Romanov and Lacaune sheep to gastrointestinal nematodes and small lungworms 总被引：1，自引：0，他引：1
The susceptibility of Romanov and Lacaune sheep to nematode parasites was studied in a permanent flock grazing an extensive pasture. The output of strongyle eggs and protostrongyle larvae was higher in Romanov ewes. Faecal samples of the Romanov ewes more often harboured Nematodirus eggs while the larvae recovered from cultures of these samples contained a higher percentage of Teladorsagia. Romanov tracer lambs had a significantly heavier adult Teladorsagia burden. This higher natural susceptibility of the Romanov breed was confirmed by experimental infections with T. circumcincta and N. spathiger but not with Trichostrongylus colubriformis. In infections with Muellerius capillaris and Protostrongylus rufescens, the worm burdens were similar but parasite fertility (larvae per adult) seemed to be higher in Romanov tracer lambs. 相似文献
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为了掌握源于安徽省金寨县牛羊肠道寄生虫感染情况,对该地区展开病原学调查,以期为该地区牛羊寄生虫病防治与诊断工作提供理论依据。该调查主要采用直接涂片法、饱和食盐水漂浮法对在金寨县的4个乡（镇）7个不同养殖场（2个牛养殖场和5个羊养殖场）采集的50份牛羊粪便进行检查,并根据形态学特征对所获得的虫卵和幼虫进行归类。经过对调查样本的检查结果显示共查出8种寄生虫,分别为犊新蛔虫、古柏线虫、扩展莫尼茨线虫、大片形吸虫、食道口线虫、夏伯特线虫、捻转血矛线虫、前后盘吸虫等。由此可见,安徽省金寨县牛羊寄生虫感染还是比较严重,因此需采取相应的防治措施。 相似文献
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The influence of daily doses of 0.05–0.1 mg fenbendazole/kg body weight on egg development was tested in twenty-seven lambs artificially infected with Haemonchus contortus plus Trichostrongylus colubriformis or Ostertagia circumcincta, as well as in two additional sheep naturally infected with Nematodirus spp.Atypical eggs were detected before a reduction in the number of eggs. Atypical eggs had blastomeres of different sizes and shapes; knot-like, crater-like or bubble-like. In isolated cases eggs with atypical first larvae were recognizable. Morphologically changed eggs occurred in the reproductive organs of female O. circumcincta worms.None, or only a very small number of third stage larvae, could be cultured from the faeces of treated sheep. 相似文献
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放牧羊线虫粪检虫卵与虫荷量相关动态的研究 总被引：3，自引：0，他引：3
对一周岁放牧绵羊同步进行为期一年的虫卵、成虫、寄生阶段幼虫动态观察。发现羊只线虫总荷量除７～９月份出现明显低谷、１２月份出现显著高峰外，其它月份均在较高水平波动。暖季宿主体内成虫占优势与虫卵排放升高季节吻合；冷季宿主体内寄生阶段幼虫居优势与虫卵排放低潮期吻合。经过对研究结果的分析，初步探索了对羊线虫病预测预报的可能性与可行性。 相似文献
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Three paddocks were contaminated with Haemonchus contortus eggs from early spring to mid summer by yearling sheep. In Paddock 1, all contamination was derived from worms that had been previously inhibited in their development. The contamination in Paddock 2 was produced only by infections recently acquired from pasture, and in Paddock 3 contamination was attributable to both sources. When the yearling sheep were replaced in mid-summer by newly weaned lambs, severe outbreaks of haemonchosis occurred on all paddocks. It was concluded that inhibited H. contortus larvae are capable of producing sufficient eggs, when they resume development, to initiate an outbreak of haemonchosis in susceptible sheep. 相似文献
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As part of a study on the epidemiology of Nematodirus species of sheep in subarctic Greenland, the development and persistence of eggs and larvae were investigated by experimentally contaminating plots of pasture with infected faeces and by placing tubes containing a suspension of eggs on to or into the soil. Despite low ambient temperatures, infective larvae appeared within a month during the summer. The greatest numbers of larvae were recovered from herbage in August and September. Eggs did not develop synchronously as development beyond the morula stage could be delayed for up to two years. Larvae were found on herbage for up to 37 months after faecal deposition. In the sheep rearing area of Greenland, therefore, Nematodirus species larvae can be present on herbage throughout the whole summer but peak numbers occur late in the grazing season. 相似文献
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S G Gherardi N Monzu S S Sutherland K G Johnson G M Robertson 《Australian veterinary journal》1981,57(6):268-271
The association of dermatophilosis with body strike of sheep caused by Lucilia cuprina was studied in a controlled environment. When sheep with areas of wet normal fleece and areas of wet fleece containing scabs induced by infection of the skin with Dermatophilus congolensis were exposed to gravid L. cuprina the files oviposited only on dermatophilosis-affected areas. In wet dermatophilosis-affected fleece, naturally oviposited L. Cuprina eggs hatched and the larvae developed to the second instar stage. Artificially implanted L cuprina eggs hatched in both wet dermatophilosis-affected fleece and wet normal fleece. In wet dermatophilosis-affected fleece the larvae from implanted eggs developed normally but in wet normal fleece they did not develop past the first instar stage. It was concluded that wet but otherwise uncomplicated dermatophilosis lesions are attractive to L. cuprina and provide sufficient protein to allow larval development to take place. 相似文献
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In studies on the control of parasitic gastroenteritis in calves and sheep, involving an annual rotation of pastures grazed by these host species, it was shown that young cattle could play an important role in the epidemiology of Nematodirus battus, a species usually regarded as a parasite of lambs. Thus, young cattle readily acquired heavy burdens of N battus in spring and the contamination of pastures with eggs from these infections resulted in significant populations of larvae on the herbage, which were infective to both calves and lambs grazed on these pastures in the following year. Although the majority of the N battus eggs hatched in the spring, some hatched in the autumn. The calves developed a strong immunity to N battus during the grazing season as demonstrated by the absence of worms at necropsy in the autumn, despite the presence of infective larvae on the pasture. 相似文献
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For oral applications, biocontrol of animal parasitic nematodes in ruminants, ion beam implanted nematode-trapping fungi must have the capacity to survive the passage through the digestive tract and be efficient in reducing infective larvae of nematodes in the faeces.Ion beams induced mutation in the spores of nematode-trapping Arthrobotrys oligospora. Mutants with genetic stability were bred. The fungi were cultured in bottles with corn kernels as growth media, and spores of different doses were, respectively, administered orally to each group of sheep naturally infected with gastrointestinal nematodes. The control group did not receive fungi. The faeces of these experimental animals were collected and faecal cultivations carried out. The fungal germination, growth, reproduction and predation of livestock parasitic nematode larvae were tested in laboratory. The efficacy of an A. oligospora N mutant in nematode-trapping larvae after passage through the digestive tract of sheep was tested. The results indicated that the ion beam implantation induced mutation of the nematode-trapping fungi is a positive mutation. The mutant spores through the digestive tract of sheep can kill livestock parasite nematode larvae in vitro. These results indicate the potential of the A. oligospora N mutant as a biological control agent for sheep nematodes.This study showed that such biotechnology could be explored for improving the effectiveness of the use of fungal infections to control livestock parasitic nematodes. This work represents the first application of nematode-trapping fungi in eukaryotic microorganisms. 相似文献
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Morphogenesis of Trichostrongylus rugatus was examined in 16 sheep experimentally-infected with 120 000 third-stage larvae and killed 2, 4, 6, 8, 10, 12, 16 and 20 days later (DAI). Third stage larvae moulted between Days 4 and 6, and fourth stage larvae moulted on Day 10 after infection. Four sheep first passed eggs in the faeces between Days 16 and 18 after infection. Rate of growth of larvae was constant between 2 and 10 DAI followed by a period of rapid growth from 10 to 16 DAI. Major features of larval development are described. Nematodes were largely restricted to the first 6 m of gut with 71% of worms occurring in the first 3 m. 相似文献