猪抗病育种研究进展

作者对开展抗病育种的必要性、发展过程、抗病的遗传基础、抗病育种方法的现状及存在的问题进行了介绍。其中对MHC、抗病主基因、抗病育种的直接、间接方法、转基因抗病育种进行了重点介绍，提出采用分子标记辅助选择和转基因工程抗病育种是当前和今后抗病育种的主要方向，最后对抗病育种将来的发展前景进行了展望。     

猪抗病育种的研究进展

抗病育种是从遗传本质上增强猪的体质,意义重大,本文在综述了几个猪抗病育种候选基因研究进展的基础上,针对当前猪抗病育种面临的问题提出了相应的解决措施,以期为猪的抗病育种工作起到一定的参考作用。     

猪抗病育种候选基因研究进展

通过抗病育种途径提高猪的抗病力,是避免养猪生产遭受疾病困扰和获得低药物残留猪肉产品的一种很有前景的方法。本文就与猪抗病育种相关的候选基因为受体类基因、免疫相关基因和信号传导基因等的研究进展作一综述,期望能为猪的分子抗病育种提供一些思路。     

猪的营养研究进展

欧洲、北美和亚洲的最新研究,指出了商品猪饲料应用营养学的研究方向。本文介绍猪营养研究最新进展的某些实例。一、体外预测饲料的营养价值猪饲料的消化率能否用酶技术模仿肠道消化在体外正确预测呢?Foulum丹麦国立畜牧研究所的科学家说:“当然能”。用这种方法大量研究证实,该法可预测饲料的回肠消化性(ilealdigestibility)和粪便消化性(faceal di-gestibility)。研究人员说,在过去二十年研究出几种实验室方法预测猪饲料消化能和氨基酸值。方法是饲料样品与酶接触,模仿肠道消化。尽管这些方法大多是很好的,但仍需从更多方面加以     

猪的疾病抗性与抗病育种研究进展

本文分别介绍了猪的单基因和多基因控制的疾病敏感性或抗性，以及对免疫反应遗传控制的研究进展，在此基础上探讨了抗病育种的可能途径。     

猪遗传抗性与抗病育种研究进展

本文从抗病力和抗性基因的遗传性出发,综述了猪主要的抗性基因及其在抗病育种中的研究进展,探讨了猪抗病育种的可能途径.     

猪维生素营养研究进展

维生素是猪维持健康与正常生长发育、繁殖所必需的微量营养成分 ,它们主要是作为营养代谢中的辅酶。近年来 ,国外对维生素研究较多 ,发现和证实了某些维生素新的作用及其推荐添加量。ＮＲＣ ( 1 988)首次提出了有效烟酸需要 ,ＮＲＣ ( 1 998)提高了妊娠和哺乳母猪维生素Ｅ和叶酸的需要量。国内尚未开展维生素需要的研究。饲养标准推荐量是由ＮＲＣ标准中能量与某种维生素的比值推算出来的。本文对最近研究较多的几种维生素的营养功能与需要作一综述。1　维生素Ａ维生素Ａ的主要功能为 :视觉、生殖、骨骼、皮肤和免疫。大量的试验表明 ,维生…     

主要抗病候选基因在猪抗病育种中的研究进展

疾病是影响畜牧生产的主要因素,虽然传统的疾病控制方法对疾病的预防和治疗起到了重要作用,但随着分子生物学和基因工程技术的发展,通过遗传育种技术,提高畜禽的抗病性与健康水平已成为当今提高畜牧生产水平的重要途径。寻找与动物生理、生化、病理、遗传连锁等方面有关的基因作为候选基因,分析候选基因的标记等位基因频率差异、标记等位基因的有无在抗性和易感性2个群体中的差异,从而间接地进行抗病育种,是一种有效的方法。本文主要对影响动物抗病力的天然抗性巨噬结合蛋白基因、干扰素基因、肠毒素型大肠杆菌K88受体基因、主要组织相容性复合体基因家族、MX抗病毒蛋白基因的国内外研究概况进行概述。     

猪维生素营养研究进展

综合评价了近几年来国内外研究较多的几种维生素 ,如维生素A、维生素D、维生素E、生物素、叶酸、烟酸、核黄素对猪的新营养作用和需要量。并结合生产实际提出了这几种维生素的推荐添加量     

Recent Advances in Swine Amino Acid Nutrition

Recent advances in swine protein nutrition are characterized by the development of functional amino acids (AA) in regulating fetal and postnatal survival, growth and development. These AA include arginine, glutamine, glutamate, proline, leucine, cysteine and tryptophan. Due to limited knowledge on AA nutrition, pork producers have traditionally paid little attention to supplementing the arginine family of AA to swine diets. Results of recent studies indicate that functional AA serve important regulatory functions in nutrient metabolism, protein turnover, and immune function, therefore enhancing efficiency of feed utilization by pigs. The underlying mechanisms include activation of nitric oxide, mammalian target of rapamycin, gaseous signaling, and AMP-activated protein kinase pathways, as well as anti-oxidative function. Dietary supplementation with arginine, glutamine, proline or leucine to weanling piglets enhances their growth performance. Arginine or glutamine is also effective in increasing milk production by lactating sows. Furthermore, supplementing arginine to the diet of pregnant gilts between days 30 and 114 of gestation increases the number of live-born piglets and litter birth-weight. Availability of feed-grade functional AA holds great promise for improving animal health and nutrient utilization in pig production worldwide. Additionally, feedstuffs of animal origin [e.g., blood meal (ring dried), feather meal (hydrolyzed), meat and bone meal, porcine protein meal, and poultry by-product meal (both feed- and petfood-grades)] are excellent and cost-effective sources of both essential and functional AA for formulating balanced swine diets. New knowledge on AA nutrition provides a much needed scientific basis for revising the next edition of swine nutrient requirements.     

Recent Advances in Swine Amino Acid Nutrition

Recent advances in swine protein nutrition are characterized by the development of functional amino acids(AA)in regulating fetal and postnatal survival,growth and development. These AA include arginine,glutamine,glutamate,proline,leucine, cysteine and tryptophan. Due to limited knowledge on AA nutrition,pork producers have traditionally paid little attention to supplementing the arginine family of AA to swine diets. Results of recent studies indicate that functional AA serve important regulatory functions in nutrient metabolism,protein turnover, and immune function,therefore enhancing efficiency of feed utilization by pigs. The underlying mechanisms include activation of nitric oxide,mammalian target of rapamycin,gaseous signaling,and AMP-activated protein kinase pathways, as well as anti-oxidative function. Dietary supplementation with arginine,glutamine, proline or leucine to weanling piglets enhances their growth performance. Arginine or glutamine is also effective in increasing milk production by lactating sows. Furthermore,supplementing arginine to the diet of pregnant gilts between days 30 and 114 of gestation increases the number of live-born piglets and litter birth-weight. Availability of feed-grade functional AA holds great promise for improving animal health and nutrient utilization in pig production worldwide. Additionally, feedstuffs of animal origin[e. g. , blood meal (ring dried),feather meal(hydrolyzed),meat and bone meal, porcine protein meal,and poultry by-product meal(both feed- and petfood-grades )]are excellent and cost-effective sources of both essential and functional AA for formulating balanced swine diets.New knowledge on AA nutrition provides a much needed scientific basis for revising the next edition of swine nutrient requirements.     

Recent Advances in Swine Amino Acid Nutrition1

Recent advances in swine protein nutrition are characterized by the development of functional a- mino acids （AA） in regulating fetal and postnatal survival, growth and development. These AA include arginine, glutamine, glutamate, proline, leucine, cyste- ine and tryptophan. Due to limited knowledge on AA nutrition, pork producers have traditionally paid little attention to supplementing the arginine family of AA to swine diets. Results of recent studies indicate that functional AA serve important regulatory functions in nutrient metabolism, protein turnover, and immune function, therefore enhancing efficiency of feed utili- zation by pigs. The underlying mechanisms include activation of nitric oxide, mammalian target of rapam- ycin, gaseous signaling, and AMP-activated protein ki- nase pathways, as well as anti-oxidative function. Di- etary supplementation with arginine, glutamine, pro- line or leucine to weanling piglets enhances theirgrowth performance. Arginine or glutamine is also ef- fective in increasing milk production by lactating sows. Furthermore, supplementing arginine to the diet of pregnant gilts between days 30 and 114 of gestation increases the number of live-born piglets and litter birth-weight. Availability of feed-grade functional AA holds great promise for improving animal health and nutrient utilization in pig production worldwide. Addi- tionally, feedstuffs of animal origin [ e. g. , blood meal （ ring dried ）, feather meal （ hydrolyzed ）, meat and bone meal, porcine protein meal, and poultry by-prod- uct meal （both feed- and petfood-grades） ] are excel- lent and cost-effective sources of both essential and functional AA for formulating balanced swine diets. New knowledge on AA nutrition provides a much needed scientific basis for revising the next edition of swine nutrient requirements.     

纳米硒在动物营养中的研究进展

硒(Se)是动物机体必需的微量元素,在机体抗氧化体系、免疫细胞功能、促生长及精子的形成和游动、前列腺素的功能等方面起着重要作用。动物体内已知存在35种以上的含硒蛋白质,其中谷胱甘肽过氧化物酶(GPx1-GPx6)和硫氧还蛋白还原酶(TrxR1-TrxR3)在机体抗氧化体系中发挥着重要的作用。国内生产中通常应用亚硒酸钠作为补硒制剂,但亚硒酸钠在使用中存在吸收率低、过氧化作用及潜在的污染等问题。有机硒和纳米硒具有吸收率高、生物活性强、环境污染小等优点。与有机硒相比,纳米硒有更显著的低毒高效性,是已发现的毒性最低的补硒制剂。近年来,纳米硒替代有机硒、无机硒源的研究已成为热点。     

鱼类镁营养研究进展

镁在大量的细胞生化反应中扮演着重要角色,它参与生物体内所有的能量代谢,催化或激活300多种酶体系.本文综述了鱼类镁的缺乏症、镁在鱼体内的吸收和代谢以及镁对鱼类生长、体组成、脂肪代谢、免疫、渗透调节等方面的影响,并阐述了镁与其他营养素的相互关系.介绍了鱼类对镁的利用率以及镁需要量的研究概况,对镁的营养生理机制做了简单探讨...     

有机硒在猪营养中的研究进展

硒为动物必需微量元素,缺乏和过量对机体都可产生不利影响,甚至死亡。硒的形式多种多样,其中有机硒具有诸多优点,成为近年来硒研究的热点。本文重点综述有机硒在猪体内的代谢和对母猪、公猪繁殖性能、生长育肥猪生产性能及肉质品质的影响。     

猪营养与营养源

营养对生物性状的表达、生产性能、经济效益有着明显的影响。营养的全部内涵包括营养素、营养源、营养水平和营养组合。营养及营养源的重要性有待深入认识。本文以猪为例,在讨论营养重要性的基础上,总结了近年来本研究室在营养源方面的研究进展,以推动这方面的深入研究。     

碘在猪饲粮中的应用

碘是人类发现的第二个必需微量元素。猪体内的碘大部分存在于甲状腺中,碘主要以甲状腺激素的形式发挥其生理作用。甲状腺激素具有细胞氧化、生长和分化、繁殖以及中枢神经系统的活性等方面的生理功能。本文对碘的营养作用、碘的应用和碘的需要量等作一综述。     

当前动物营养学发展的几个方向

动物营养学是一门主要以动物生理学和动物生物化学为基础,揭示营养物质在体内的代谢机理、规律及功能、研究发挥最大遗传潜力对各种营养素的适宜需要量以及评定饲料对动物的营养价值的应用基础科学,它是沟通动物饲养学与动物生理生化等基础学科的桥梁,最终目标是为畜禽饲养中科学配制全价平衡高效饲料,用最少的饲料投入向人类提供量多、质优且安全的畜产品,同时减少畜牧生产对环境的污染,保护生态平衡,