鱼类的维生素C营养

<正>维生素C(VC)是一种重要抗氧化维生素,摄入的VC与动物的健康息息相关。对鱼类来讲,VC不仅可以促进生长,而且还可以维持正常的生命活动。但是,在很多鱼类中缺少合成VC的关键酶——L-古洛糖酸内酯氧化酶,需要在饲料中添加以满足需求。缺     

维生素C对鱼类功用的研究进展

1VC对鱼类的促生长作用VC是鱼类正常生长所必需的。在饵料中添加适量的VC对其生长是有促进作用的,这方面的研究结果比较一致。Y.LIandR.T.Lovell(1985)报道,用0-3000mg/kg6个浓度的VC饲喂海鲶鱼后,两组鱼的末重都显著高于对照组(0/mg),而且添加的     

维生素C对鱼类生长、繁殖、抗氧化和免疫的影响的研究进展

维生素是一种微量的有机物质，是保持机体健康的必要营养素。由于多数鱼类自身不能合成维生素或者合成量少，所以必须从饲料中获取。维生素C(VC)是大多数鱼类正常生长和生理功能所必需的微量营养素之一。缺乏VC会引起一系列生理功能障碍或代谢紊乱的症状，例如身体结构畸变（脊柱弯曲、眼睛、鳃和鳍等软骨的变形）、内出血、尾侵蚀、体色变黑和生长缓慢等。VC对鱼类的生长发育、伤口愈合、铁代谢、胶原的形成、应激反应和繁殖等方面发挥重要作用。文章综述了VC的生理特性、VC对鱼类生长、繁殖、抗氧化和免疫的影响以及缺乏VC对鱼类的影响，以期为VC在鱼类生产中的应用提供参考。     

鱼虾饲料的几种新型VC添加剂

鱼类缺乏维生素会影响鳃盖的发育,破坏胶原蛋白的合成,阻碍脊柱的生长.并引起内出血和其它一些问题。VC有促进体内铁吸收、防止贫血症的作用。 中国鲤鱼、鲇鱼,鲑鱼等许多鱼类都有关于因VC缺乏引起疾病的报道。部分鱼类VC的需要量见表1。养殖的虾也必须补充VC。     

鱼类脂类代谢调控机制

<正>近年来关于鱼类脂类营养研究较多,但鱼类脂类代谢机制方面还缺少相应的资料。如何满足鱼类脂肪营养需求,不仅节省蛋白质和多不饱和脂肪酸,而且可以最大限度的利用廉价脂肪酸,这方面的内容会直接影响鱼类代谢和饲料质量。因此,了解和掌握鱼类脂肪代谢规律,对于研究鱼类营养非常重要。     

家禽饲料中添加维生素C效果明显

据研究,某些动物可以通过物质转换在体内生成维生素。比如,维生素C(抗坏血酸)对人类和灵长类动物来说是必需的,而家禽、反刍动物则可通过代谢作用将葡糖酸转换生成 VC。最新研究发现,合成VC的品质不良会阻碍幼龄动物充分发挥其应有的效果。在一定的条件下(比如应激),饲料中添加VC是有效的。对于处于生长发育期的动物投与VC还能促进生长。鸡的日龄与VC的投与量具有重要的相关性。试验查明,出壳1周龄以内的雏鸡只能生成少量的VC。15日龄前的雏鸡1日中其肾脏可生成3毫克VC输送给其他脏器。另据报道,随日龄的增     

不同绥释处理氨基酸在异育银鲫饲料中的利用效率研究

鱼类对蛋白质的需求,实质上是对必需氨基酸和非必需氨基酸的需求。当鱼类摄取的饲料中各种氨基酸的组成比例和含量比较合理,其吸收到体内的各种氨基酸就能更有效地被合成新的蛋白质。在通常情况下,饲料的配方成本决定了主要蛋白源的结构组成,往往会导致必需氨基酸组成与鱼类的营养需求相差较大。因此,研究者们试图通过补充外源性氨基酸的方式,使饲料中的必需氨基酸组成更趋于满足鱼类的需求。     

不同缓释处理氮基酸在异育银鲫饲米斗中的利用效率研究

鱼类对蛋白质的需求,实质上是对必需氨基酸和非必需氨基酸的需求.当鱼类摄取的饲料中各种氨基酸的组成比例和含量比较合理,其吸收到体内的各种氨基酸就能更有效地被合成新的蛋白质.在通常情况下,饲料的配方成本决定了主要蛋白源的结构组成,往往会导致必需氨基酸组成与鱼类的营养需求相差较大.因此,研究者们试图通过补充外源性氨基酸的方式,使饲料中的必需氨基酸组成更趋于满足鱼类的需求.     

VC-2-聚磷酸酯(LAPP)稳定性和生物利用率

VC对鱼虾类营养的重要性逐渐为人们所认识。但结晶VC由于受光、热、氧、无机盐、湿度等的影响很容易失去活性。而饲料加工过程使VC极易被破坏。制粒后的贮存、饲喂时的水浸也会使饲料中VC受损失。为了改善VC的稳定性,使之更适用于饲料,人们开发出多种稳定型 VC商品,如 VC钙钠盐、包膜 VC(包括乙基纤维素、脂肪和硅酮等包膜剂包被VC的产品)、VC衍生物(如VC- 2- 硫酸脂、VC-2- 单磷酸脂、VC脂肪酸脂、VC- 2- 聚磷酸     

鱼类饲料配制中的营养问题

鱼类是栖息于水中的变温动物,它们与陆生的畜禽比较,虽然物质代谢的原理相同,但鱼类的消化器官及其机能、对饲料的要求和营养需要等方面却与畜禽有很大差异。为了充分发挥鱼类的生产潜力,在鱼类饲料配制中必须注意其营养需要的特点,现简要分述于下。1 能量和蛋白能量比 鱼类生长发育,首先需要能量,饲料能量是鱼类营养中最基本的营养需求,是鱼类饲料     

Disease and destiny-mystery and mastery

When early people made their appearance, zoonotic infectious diseases were already waiting, but epidemic diseases did not appear in human history until people began to live in large numbers under conditions of close contact, mainly during the last 10,000 years. Disease has decimated urban populations, conquered armies, and disrupted society. The focus here is on (1) the plague of Athens and the Black Death; (2) smallpox, influenza, and rabies; (3) avian influenza prion diseases, and foot & mouth disease; and (4) emerging and re-emerging diseases. All have veterinary public health associations. In Athens, Greece, in 430 BC, when the Spartans ravaged the countryside, hordes crowded into Athens so that orderly movements, space in which to live, and adequate supplies of food became impossible. Crowding of any population fosters disease transmission; chaos and disorder enhance it all the more. Out of northern Egypt came a terrible plague from across the Mediterranean Sea. The identity of the plague of Athens remains unsure, but the well-considered conclusion is Rift Valley Fever, a mosquito borne, viral zoonosis. The Black Death, also called the Plague, raged in Asia for centuries. In 1347, the Black Death was brought by a ship out of Asia to Sicily. The scenes of devastation were repeated throughout Europe, with 90% or more of the people dying in city after city. Influenza, too, has been a cause of periodic human epidemics, but the great pandemic of influenza occurred in the last months of World War I. In the years of highest occurrence, more than half the world's population became clinically infected. If veterinary public health had been born earlier, it could have led to elucidating the epidemiology of influenza and the plagues of Athens, Europe, and Asia. In turn, smallpox had also caused continual tragedy. In 1796, Edward Jenner began to harvest pustules of cowpox from children or infected cows and inject them into susceptible children. In 1980, the World Health Organization declared that smallpox had been eliminated from the world. Rabies, though, still strikes terror. A number of animal diseases, broadly termed emerging and re-emerging diseases, need surveillance because they have the potential to impact human health. From late in 2003 to 2007, the highly pathogenic H5N1 influenza virus in poultry infected at least 121 people and caused 62 deaths in four countries. The prion diseases, too, all have very high numbers in concentrated contacts. To control these diseases, veterinary public health is essential, with diagnosis, epidemiological surveillance, clinical manifestations, and prevention as primary measures.     

Foot and mouth disease and bluetongue: differences and similarities

On 26th of july 2007 a new case of bluetongue was notified in the Netherlands and on 2nd of august 2007 foot-and-mouth disease was diagnosed in Surrey, England, which raised the threat of having both infections simultaniously in one area. Bluetongue and foot-and-mouth disease have a different pathogenesis, but symptoms may resemble each other at a later stage of infection. The pathogenesis and possible clinical symptoms of both infections are discussed and illustrated with pictures.     

德国荷兰畜禽产品质量安全交流与启示

2018年岁末,笔者有幸赴德国和荷兰,就畜产品质量安全控制及检测技术等进行了短期交流,收获颇丰,现具体介绍如下。一、交流情况德国面积35.73万平方千米,人口约8175.2万,是欧盟人口最多的国家,农业发达,机械化程度很高。德国的畜牧业以猪、牛、羊和禽类为主,畜牧业产值占农业生产总值的61%。德国虽然农业比重很小,但却是有机农业运动最早的发起国,也是目前世界上有机农产品生产与消费大国。     

奶牛肢蹄病及其防治

简介常见奶牛肢蹄病种类及其症状,从日粮营养、运动场地面结构、环境卫生、饲养管理、遗传育种、疾病管理等方面简析奶牛肢蹄病的病因,并提出相应的预防措施。     

畜禽物种多样性及其保护和利用

文章就我国畜禽物种多样性资源的现状、保护和利用等方面进行阐述,为生态脆弱的喀斯特地区畜牧业可持续发展提供参考。     

马的咽气癖及其防制措施研究进展

在动物的异常行为中以刻板行为最为常见,而咽气癖又是马最常见的口部刻板行为之一。作者就咽气癖在生理方面和心智方面对马体产生的影响、行为基础、诱因的研究进展及常见的防治措施进行综述。     

牛羊焦虫病诊断与防治技术

近几年来,辽宁省牛羊饲养业迅速发展,焦虫病的危害越来越明显,已成为危害牛羊的主要疾病之一。为了提高牛羊焦虫病的防治水平,保证我省牛羊饲养业的健康发展,笔者在参阅文献和同行们诊疗经验的基础上,结合自己的治疗实践,详细阐述了我省牛羊焦虫病近几年的流行特点和诊断防治方法。     

国内外蛋氨酸与赖氨酸市场分析与展望

近几年,世界饲用添加剂市场增长较快,预计今后将进一步增长,据世界粮农组织(FAO)首领会议的倡议,到2015年,将使世界营养不良的人口削减一半,其间,肉制品将会以每年2％的速度增长,特别是加快猪肉和禽肉增长。这将促进世界添加剂,尤其是蛋氨酸和赖氨酸需求量的增加。