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Ma M Guan G Lu B Liu A Liu Z Chang Z Li F Chang F Luo J Lu W Zhang Q Yuan G Yin H Boulard C 《Veterinary parasitology》2003,117(1-2):147-151
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. 相似文献
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Yin Hong Lu Wenshun Zhang Qicai Lu Wenxiang Luo Jianxun Dou Huifang 《Tropical animal health and production》1997,29(4):30S-32S
Tropical Animal Health and Production - Two experiments were carried out to determine ifBabesia major could be transmitted byBoophilus microplus. In experiment 1, aBabesia-free batch of laboratory... 相似文献
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枇杷属植物落黄叶片颜色遗传多样性分析 总被引:1,自引:0,他引:1
调查发现枇杷属(Eriobotrya)植物种质落黄叶片有红褐色、金黄色、紫红色等24种代表性色泽。通过便携式色差仪观测枇杷属10个种176份种质落黄叶片正面和背面的色泽参数,探讨落黄叶片颜色的遗传多样性特征。结果表明:(1)枇杷属植物落黄叶片正面和背面的色泽参数L、a、b值变异系数差异较大,变幅为8.65%~185.30%,Shannon’s遗传多样性指数为1.95,说明落黄叶片色泽变异多样;(2)不同种质类群间和不同来源地类群间的变异系数和Shannon’s遗传多样性指数差异均较明显,呈现出栽培驯化程度越高,落黄叶片正面和背面的b值变异系数越小和a值变异系数越大的趋势;云南、贵州、福建地区的类群多样性指数较高;(3)系统聚类将落黄叶片正面色泽划分成12组,背面分成10组,且各组内所包含的枇杷种质类型差异大;(4)L值、b值对落黄叶片正面和背面的系统聚类分析贡献率均较大,落黄叶片正面L值与背面b值呈极显著正相关;(5)落黄叶片颜色的遗传多样性可作为枇杷属植物形态学特征描述的补充,为枇杷属植物的鉴别和利用提供新的参考,对枇杷分类研究具有潜在价值。 相似文献
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Lu Wenshun Lu Wenxiang Zhang Qicai Yu Feng Dou Huifang Yin Hong 《Tropical animal health and production》1997,29(4):16S-18S
Tropical Animal Health and Production - This paper described studies on the distribution, vector and multiplication of the pathogen of ovine anaplasmosis and a complement fixation test (CFT) for... 相似文献
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Experiments were undertaken to determine the mode of transmission to cattle of an unnamed Babesia sp. by Hyalomma anatolicum anatolicum, Hyalomma detritum, Hy. rufipes koch, Haemaphysalis longicornis and Boophilus microplus. The unnamed Babesia species designated Babesia U sp. was isolated by infesting cattle with nymphs from female Hy. a. anatolicum ticks collected from Xinjiang province. Adults of laboratory reared Hy. a. anatolicum, Hy. detritum and Hy. rufipes koch were infected with Babesia U sp. by feeding on infected cattle, isolated with nymphal ticks of Hy. a. anatolicum derived from females collected from field. The experiments revealed that Hy. a. anatolicum was capable of transmitting Babesia U sp. transovarially in larval (2 of 4 calves), nymphal (6 of 6 calves) and adult (3 of 8 calves) stages, with prepatent periods of 16, 12, and 8 days, respectively, and that this Babesia was also transovarially transmitted by both the nymphal and adult stages of Hy. detritum and Hy. rufipes. Attempts to transmit this Babesia U sp. transovarially with Hae. longicornis and B. microplus, and transstadially with Hyalomma spp., were carried out, and the results proved to be negative. 相似文献
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Experiments on the transmission of an unidentified Theileria sp. infective for small ruminants by Haemaphysalis qinghaiensis and Hyalomma anatolicum anatolicum were carried out. Three Theileria-free batches of adult, larvae, and nymphs of laboratory reared H. qinghaiensis and Hy. a. anatolicum ticks were infected by feeding them on sheep infected with Theileria sp. The Theileria sp. was originally isolated from adult ticks of H. qinghaiensis, by inoculation of blood stabilates or tick transmission. H. qinghaiensis has been shown to be capable of transmitting the Theileria sp. infective for small ruminants transstadially to sheep and goats. The nymphs developed from the larvae engorged on the sheep infected with the parasite transmitted the pathogen to splenectomized sheep with prepatent periods of 30, 31 days, respectively; but the subsequent adult ticks of H. qinghaiensis derived from the nymphs did not transmit the pathogen to sheep. However, adults developed from the nymphs engorged on the sheep infected with the parasite transmitted the pathogen to sheep with prepatent periods of 24-27 days. The larvae, nymphs and adult ticks derived from female H. qinghaiensis ticks engorged on infected sheep were not able to transmit the parasite transovarially. The same experiments were done with Hy. a. anatolicum, but examination for presence of piroplasma of Theileria sp. from all animals were negative, demonstrating that Hy. a. anatolicum could not transmit the organism to sheep or goats. 相似文献
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本文以国内外农田防护林的大量观测资料为基础,划分了农作物在防护林保护下产量田间分布的主要类型,并借助计算机进行定量分析,提出且验证了相应的数学模型(FNC-I~FNC-Ⅳ),经F检验,有85.7%的实例超过了O.05的显著水平。最后从作物总产计算、对照点模拟、带距优化三方面简介了模型的应用。 相似文献
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