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雄蚕新品种限7×平48饲养性状比较 总被引：2，自引：1，他引：1
通过对雄蚕新品种限7×平48与秋华×平30的饲养比较表明：限7×平48的张产茧53．54蚝、干壳量9．85g、张种收入834、08元，比秋华×平30的张产茧48、61kg、干壳量9．50g、张种收入757、35元，分别增加了10．14％、3．68％、76、73元。对雄蚕新品种限7×平48与秋丰×白玉的饲养比较表明：限7×平48的张产茧43．20蚝、干壳量9、60g、张种收入673．05元，比秋丰×白玉的张产茧41、30蚝、干壳量8．35g、张种收入636．02元，分别增加了4．60％、14．97％、37．03元。限7×平48解舒率为75．61％、出丝率为42．17％，比秋华×平30提高10．77与1．39个百分点，比秋丰×白玉提高4、38和5．24个百分点。该品种具有容易饲养、产量高、茧质好等优点，可以在生产上继续扩大试养及推广。 相似文献
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饲养雄蚕品种是提高蚕丝品质和蚕茧生产效益的重要途径之一。以引进的性连锁平衡致死系S-14为母本,用普通家蚕品种夏6为优良性状基因供体回交改良性连锁平衡致死系,经2轮杂交、自交、回交组成的循环改良和纯化,育成经济性状优良的家蚕性连锁平衡致死系平48,将该品种与家蚕限性皮斑品种限7组配成夏秋用雄蚕杂交组合限7×平48。经浙江省家蚕新品种实验室联合鉴定,该雄蚕品种的雄蚕率达99%以上,在农村生产鉴定试验中表现出强健好养、产量高、丝质优等特点:张种产茧量和50 kg桑产值分别较对照品种秋丰×白玉提高8.4%和9.4%;茧丝长、解舒丝长、解舒率和干茧出丝率分别较对照种提高7.9%、12%、2.57个百分点、1.54个百分点。新品种2009年通过浙江省家蚕新品种审定,适合在长江中下游蚕区的夏秋季饲养。 相似文献
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利用雌蚕无性克隆系的新型雄蚕品种选育及应用 总被引：1，自引：1，他引：0
利用性别控制技术实现"农村专养雄蚕,蚕种场多养雌蚕"对提高蚕茧生产的茧丝产量和品质,以及降低雄蚕杂交种的生产成本具有重要意义。将育成的高发生率和高孵化率雌蚕无性克隆系与平衡致死雄蚕杂交,按不完全双列杂交方法组配成31个雄蚕杂交组合,通过3年5期的比较试验,从中筛选出综合经济性状优良的新型雄蚕品种雌35×平28和雌29×平28,并在浙江主蚕区成功试养。新型雄蚕品种与现行雄蚕品种相比,张种产量提高8.53%,解舒丝长增加45m,鲜茧出丝率提高0.7个百分点。新型雄蚕品种的育成有望进一步降低雄蚕杂交种的生产成本,加速专养雄蚕产业化的进程。 相似文献
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“雌35×平28”是浙江省农科院蚕桑研究所新型雄蚕品种，经2013年引进试验。本文总结了“雌35×平28”的农村试养情况，结果表明该品种综合性状优良，大部分指标优于“秋华×平30”。 相似文献
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杭州蚕种场从2012年开始,在淳安原蚕区进行雄蚕品种"秋华×平30"试繁。通过三年实践,逐步掌握了原蚕区基地雄蚕繁育的技术要点,实现了雄蚕繁育的稳产优质。本文介绍了雄蚕品种"秋华×平30"的发育经过、饲养标准和在原蚕区繁育该品种的技术要点。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献