Amino acid nutrition in egg production industry

The egg production industry is facing various problems that need to be solved. For amino acid nutrition to achieve scientific and economical feeding of laying hens, it is necessary to elucidate the content, digestibility, or availability of nutrients of feedstuffs and feeds and the requirement of amino acids for laying hens. In addition, improvement to quality of eggs and meat of spent hens, methods of management and development of new feedstuffs are essential. For sustainable animal production, decrease in excreta and animal welfare should be studied. The real‐time determination of content and digestibility of amino acids in feedstuffs are essential for formation of feeds. Recent advances in the near infrared reflectance analysis will be able to determine the content, digestibility and availability of nutrients in feedstuffs and feeds, if we have a supplemental amount of conventional analysis to define the calibration population. The amino acid requirements are affected by various factors. Therefore the method to quickly and exactly determine amino acid requirements in response to various factors is necessary. By using plasma free amino acid concentration as a criterion, it is possible to determine amino acid requirements in various conditions of laying hens within a short experimental period, repeatedly using the same animals. Because the amino acid requirements differ among individual animals, it should be expressed as grams per hen per day. Practically, it is impossible to formulate various feeds for individual hens. The various expressions have been developed and these expressions have advantages and disadvantages. The nitrogen excretion of laying hens is easily reduced by reducing dietary nitrogen levels and restricting the feed intake. The availability of amino acid may be improved by feeding management, and supplementing enzyme, but the quality of eggs and meat of spent hens and welfare of laying hens are not affected by amino acid nutrition.     

家蚕抗血液型脓病新品种桂蚕N2的选育

桂蚕N2是广西蚕业技术推广总站选配育成的第一对抗家蚕血液性脓病的强健性夏秋用家蚕新品种,省级实验室联合鉴定和农村试验鉴定表明：该品种适合广西等亚热带地区饲养。在常规条件饲养下,蚕体强健性、蚕茧产量和质量等主要经济性状与对照种两广二号相仿或略有提高;该品种在2龄起蚕经口添食NPV多角体病原的LC50（半数致死浓度）为1×10^9个／mL,比两广二号对照高1000倍,表现出较强的抗NPV特性。桑蚕品种桂蚕N2综合经济性状稳定,已通过品种鉴定,可以在广西各蚕区全年各蚕期饲养,特别在家蚕血液型脓病多发的蚕区和夏秋期饲养,更能表现出其强健丰产的效果。     

增强子诱捕研究进展及其在家蚕中的应用展望

增强子诱捕是研究基因与调控元件功能的有力工具,自1979年建立以来,已在原核生物、真核生物和哺乳动物中得到了广泛应用。家蚕作为重要的鳞翅目模式昆虫,随着其基因组测序的完成,家蚕研究进入功能基因组时代,增强子诱捕技术有望在家蚕新基因的发现和功能研究方面发挥重要作用。本文简要概述了增强子诱捕的研究进展,并展望了其在家蚕中的应用前景。     

贵蚕七号原蚕羽化及产卵性能研究

为掌握贵蚕七号组合原蚕781×57A和7532×826的羽化和产卵性状,进行了原蚕羽化发蛾习性研究以及原蚕雌蛾产卵速度和不同交配时间对卵质影响的研究,结果表明:原蚕羽化集中,雌蛾拆对后7h盛产卵,产卵快而集中,卵质优良。两原种对交时间在1—4h,随着交配时间的延长,不受精卵减少,产卵量增加。     

基于SCI文献分析家蚕相关研究进展

使用Thomson Data Analyzer及Excel软件,通过对SCI—EXPANDED中2002—2010年的家蚕文献的文献类型、主要国家／地区分布、研究机构、作者、来源期刊、学科分布及关键词进行统计分析,以文献为依据看近年来家蚕研究的发展动态与趋势。MAI指数分析表明近两年我国家蚕研究已处于世界领先水平。关键...     

添食壳寡聚糖对家蚕茧质影响的初步研究

以夏芳、秋白品种为对象,研究添食壳寡聚糖对家蚕主要经济性状的影响.结果表明:3龄蚕和5龄雄蚕添食壳聚糖与对照相比,蚕的生长和茧质指标均无明显差异;5龄雌蚕添食壳聚糖与对照相比,解舒率显著增加,平均粒茧落绪次数显著减少,而其他指标均无明显差异.     

家蚕卵无胶着力基础品种的创建

用多元杂交方法，育成蚕卵无胶着力兼斑纹限性基础品种9357、9214等，其综合经济性将达到实用水平，并配成四元杂交种在农村试用，效果良好。     

“一化二放”秋柞蚕制种生产试验简报

为充分利用鲁山县柞坡资源,2015年进行了"一化二放"秋柞蚕制种生产试验,取得了种茧羽化率34%、蚕卵孵化率80%以上、平均单产118.5kg的好成绩,总结探索出一化性柞蚕种茧感光制种实用技术。     

sch基因在家蚕性别控制及单养雄蚕品种选育上的应用研究

将伴性赤蚁基因导入经济性状优良的实用家蚕品种 ,育成单养雄蚕实用系统纯系夏sch、秋sch ,其经济性状基本达到实用水平。配制的夏芳×秋sch、秋白×夏sch为单养雄蚕杂交种 ,实验室和农村小区试验证明其茧丝质成绩明显优于对照 ,可在生产上推广应用 ,并且可降低雄蚕品种的繁育成本。     

臭氧对家蚕病原体的消毒效果研究

研究了臭氧对白僵菌、曲霉菌、家蚕核型多角体病毒(BmNPB)和B.t芽孢的杀灭效果,浓度为40mg/L的臭氧对病毒和B.t芽孢没有杀灭作用,浓度10mg/L的臭氧对曲霉菌没有杀灭作用,浓度15mg/L的臭氧对白僵菌有轻微的杀灭作用,因此在现有条件下臭氧在蚕业生产中不会有很好的应用。