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试论江苏省蚕品种育种方向与措施 总被引：1，自引：0，他引：1
<正>江苏省是全国重点蚕区之一,建国以来蚕桑生产得到迅速的发展。江苏省家蚕品种随农村蚕桑生产情况的变化与工业、贸易的需求,进行了数次更换。每一次品种的更新推广,都促进了蚕丝业的发展。纵观全省蚕品种的更换及现行品种的性状等方面,与当今科技发展的速度看,我省蚕品种的选育方面还存在着一定的差距,本文将根据我省现行品种的现状,今后蚕品种选育方向与措施等作简单的浅论,供同行商榷。 相似文献
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本文通过对四川近20年蚕品种审定和推广应用情况,分析了我省蚕品种推广历程,大多数蚕品种育成后推广数量少甚至根本没有推广的原因。当前随着我国城乡一体化建设步伐的加快,农村人口和劳动力的减少,蚕品种如何适应省力化、规模化的现代蚕桑产业发展的需要,这是摆在育种工作者面前的新课题。产业要发展,品种应先行,选育"高抗、优质、高效"的蚕品种势在必行,才能促进蚕桑产业可持续发展。 相似文献
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浙江省蚕桑学会主持召开的"蚕品种选育与蚕种检验办法改革学术讨论会"于1984年12月26～28日在浙江省农科院举行.参加会议的有各地(市)的省蚕桑学会会员代表共32人,他们分别来自蚕种场、学校、科研以及蚕种生产主管单位,收到有关学术论文6篇.与会代表就加速我省蚕品种的选育、鉴定、推广以及改进蚕种检验办法进行了发言和讨论,并参观了省农科院蚕桑研究所最 相似文献
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芙蓉、湘晖这对夏秋用品种,我省自1986年从湖南引进以来,已为江西的蚕桑生产发展起了积极的作用。该品种具有比较好养,茧丝较优的特点,深受广大蚕农和丝绸部门的好评,到目前为此,全省的夏秋蚕用种大部分是芙蓉×湘晖及其反交(除蚕种缺口从外地购进外)。已成为我省夏秋蚕的当家品种。随着省蚕桑工程实施以来,蚕桑生 相似文献
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<正> 由江苏省农林厅召开的江苏省蚕桑生产、区划会议于1月13日——17日在浒墅关蚕种场召开,出席会议的有来自全省10个地区、市近70个县蚕桑生产主管部的133位代表。省农委区划办公室、中国农业科学院蚕业研究所、江苏省蚕种公司、苏州蚕桑专科学校等单位亦派员参加了会议。这次会议是我省蚕桑生产上的一次盛会,因为这个会不仅是蚕桑生产会,又是蚕桑区划会,蚕品种签定会,桑品种签定会,蚕种场原种会,蚕学会理事会,也是全省蚕茧产量超过历史最高水平的一次庆功会。朱竹雯副厅长作了“再接再励,乘胜前进为夺取1981年蚕茧优质丰产而努力”的报告,报告说:我省蚕茧生产形势和全国一样,取得了连续大幅度增产,1980年全省蚕茧总产 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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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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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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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 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
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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