雄蚕繁育基地化的探索

用家蚕性连锁平衡致死系的雄性与常规家蚕品种的雌性相交,下一代雌性在胚胎期死亡,仅雄性能正常孵化、发育并结茧,可实现专养雄蚕,从而实现农村专养雄蚕这一蚕业技术的革命,为实现蚕业的高效、省力奠定了技术基础。2005年,秋·华×平30由浙江省农科院蚕桑所培育并通过浙江省省级审定,同时也是国内外第一个通过审定的雄蚕品种。杭州地区是全国率先大规模推广雄蚕品种的蚕桑主产区,杭州蚕桑技术推广总站也是较早繁育雄蚕杂交种的专业蚕种场站。由于雄蚕繁育难度大、繁育系数低、繁育成本高,加上杭州蚕桑技术推广总站由专业场向原蚕业转移等原因,导致中间有几年繁育间断。为实现雄蚕杂交种繁育自主化,促进杭州地区雄蚕的大面积推广,从2012年开始,杭州蚕桑技术推广总站开始在原蚕区进行雄蚕品种秋·华×平30这一对品种试繁。经过6年的实践,不断摸索经验,逐步掌握了原蚕区雄蚕繁育的技术,实现了雄蚕繁育稳产、高产、优质的综合目标,在此与大家共同探讨下繁育中的经验和教训。     

雄蚕系列品种一代杂交种繁育重点问题探讨

湖州市从1997年春期率先引进雄蚕系列品种并在农村进行试养推广,至今已推广数对雄蚕品种并取得了令人满意的成绩.2000年春期开始,塔山蚕种制造有限公司作为国内外第-个批量繁育雄蚕种的生产单位开始接受一代杂交种的繁育,以后其他蚕种制造企业都陆续参加了雄蚕系列品种的繁育.经过多年的实践,对雄蚕繁育积累了一定的体会,在此与各位共同探讨.     

雄蚕杂交种特点及繁育技术

专养雄蚕技术作为一项蚕桑的技术革命，目前已进入实用推广阶段。在实际推广应用过程中，由于雄蚕杂交种的制种特点，决定产生同样鲜茧量的蚕种繁育成本显著高于常规杂交种。如何降低雄蚕杂交繁育成本。成为推广雄蚕技术需要解决的主要瓶颈之一。     

仙居县雄蚕推广初见成效

加强雄蚕品种的选育,实现专养雄蚕和实用化推广是新世纪蚕业科学基础性研究的重要课题之一.然而,雄蚕一代杂交种的饲养技术及其价格偏高等问题,给推广工作带来一定难度.仙居县于2000年晚秋开始从浙江省农科院蚕桑研究所引进少量雄蚕种进行试验,获得成功.随后,采取试验示范、宣传辅导、政策引导等多项措施,推广工作相对比较顺利.     

原蚕饲养更要注重减少不良蛹的发生

蚕业生产早在２０年代就开始利用一代杂交种，对提高蚕茧的产量和质量，促进蚕业生产的高速发展，起到了积极作用，同时又推动了蚕种生产的发展。解放后，我省繁育一代杂交种，主要集中在专业蚕种场，少量的原蚕区种场，原蚕饲育也都是集体饲养，因此比较容易管理，也易于...     

新型雄蚕品种“浙凤2号”繁育初试

针对雄蚕品种制种成本较普通杂交种高的问题,通过利用雌蚕无性克隆系与平衡致死系交配的方式,以提高雄蚕种的制种效率、制种质量及繁育效益。于2016年晚秋进行了新型雄蚕品种"浙凤2号"的原蚕区嵊州床江村繁育试验,饲养成绩、制种过程稳定,制种结果符合预定的目标,试验取得初步成功。     

影响原蚕区种茧质量的原因与对策

<正>重庆市蚕业科学技术研究院(下称研究院)系2011年7月由原重庆市北碚蚕种场、重庆市西里蚕种场合并组建而成的公益类农业科研事业单位,隶属于重庆市对外贸易经济委员会,主要职能为专业从事蚕桑新品种和蚕业应用技术研发与推广。其一代杂交种生产数量位居重庆市首位,是重庆乃至西南地区重要的蚕种推广基地,“桑椹牌”、“桑叶牌”蚕种在业内和广大蚕农中享有良好声誉。研究院一代杂交种繁育主要靠原蚕区饲养原     

雄蚕种在农村原蚕区繁育中的体会

海盐县雄蚕种在农村原蚕区繁育中，通过对基地的选择与扶持、与科研单位协作攻关、提高群众繁育雄蚕种生产技能、增加投入、开展试验等措施，使基地的雄蚕种繁育技术不断得到完善，形成了一定的生产能力；建议继续加大对原蚕区农户的反哺力度，进一步挖掘雄蚕种繁育潜力，加快雄蚕品种的推广。     

开发高新技术推广雄蚕品种

雄蚕的繁育与推广是提高蚕茧出丝率，增加茧丝绸生产经济效益的重大突破口，是二十一世纪蚕业发展的科技制高点。为在蚕业高科技领域拥有一席之地，迅速提升我县茧丝绸生产的经济效益，为新世纪我县蚕业的可持续发展打下坚实基础。我站于１９９９年开始从浙江省农科院蚕研所引进繁育、试养与推广了雄蚕品种，到２０００年晚秋蚕止，共计繁育了雄蚕品种１８００余张。其中饲养了第一代雄蚕种夏５×平２、夏４×平１。第二代雄蚕种夏华×平８共三对品种计３２３张。１ 推广雄蚕品种的主要实绩２．１ 雄蚕品种（尤其是第二代）具有强健好养、食…     

全面高效防微粒子病是成功经营原蚕区的关键

<正>由于苏州城市化进程的加快,地处苏州高新区的江苏省浒关蚕种场场内桑田日益减少,从 1996年开始,每年95％以上的一代杂交种都在十多个农村原蚕区生产,可以说是一个名副其实的原蚕区蚕种场。但是,每年总有几个原蚕点的微粒子毒率偏高或存在安全生产隐患,蚕种时有淘汰。原蚕区大都分布松散、设施落后、饲养水平参差不齐,一旦有微毒,极易增殖扩散污染整个生产     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

商会自治的基石——商会自治规范研究

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。     

猪毛色遗传的研究进展

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。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

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。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

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.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

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。     

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.