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991.
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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993.
OBJECTIVE: To evaluate a rapid polymerase chain reaction (PCR) fingerprinting technique for discriminating among Pasteurella multocida isolates from laboratory rabbits. SAMPLE POPULATION: 33 P multocida isolates from rabbits with clinical pasteurellosis. PROCEDURE: PCR assays were conducted with 2 minisatellites (core sequence and modified core sequence of phage M13) and 2 microsatellites ([GTG]5 and [GACA]4). Each bacterium was assigned to a PCR type for each of the primers used. Boiled bacterial extracts and purified genomic DNA were compared by use of PCR assays for phage M13 and (GACA)4. Plasmids were isolated from each bacterium, and their influence on PCR fingerprint was determined, using boiled extracts as a DNA source. RESULTS: M13 core sequence and M13 modified core sequence yielded 5 and 8 PCR types, respectively. The microsatellites (GTG)5 and (GACA)4 yielded 4 and 9 PCR fingerprint types, respectively. Fingerprint patterns obtained by use of isolated DNA differed from those obtained by use of boiled extracts, although discrimination among P multocida isolates was similar. The presence or absence of plasmids did not affect PCR fingerprints. CONCLUSION: Single primer PCR fingerprinting with minisatellite and microsatellite primers is an efficient and reproducible method for the discrimination of P multocida isolates from rabbits and can be performed directly, using boiled bacterial extracts as a source of template, although more bands were obtained from pure genomic DNA. 相似文献
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995.
在保存家蚕突变基因资源过程中调查发现:黄血蚕蛾翅在羽化之初呈鲜黄色,白血蚕均不然。通过与白血蚕(非黄翅)和黄血抑制基因(I)进行杂交试验,分析黄翅的遗传规律,结合普查家蚕突变系统蛾翅色性状,证明黄翅性状与幼虫黄脚一样,为黄血基因支配。进而记录了因黄血基因的多效作用在卵、幼虫、茧、成虫各阶段表现的形态特征。 相似文献
996.
低脂奶牛日粮会提高风味干酪内源脂肪酸中硬质脂肪水平、蓝干酪风味甲基酮和桃色椰子风味δ-内酯的前体物,而高脂奶牛日粮则与之相反。日粮在瘤胃中产生的丙酸代谢能从日粮油酸中形成芳香味的γ-十二烷内酯、从日粮亚油酸中形成芳香味的γ-十二-顺-6-内酯。味美牧草会产生富含颜色的奶脂肪,并把植醇、二氢植醇、植物烯、植二烯以及它们的低等同族体引入到奶脂肪中。无蛋白合成日粮会降低动物风味的吲哚和粪臭素。 相似文献
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