钒的生物学功能及其最新研究进展

本文简要地介绍了钒的生物学功能及其研究历程,其主要内容包括钒对机体糖代谢、脂代谢、造血功能、繁殖机能、心脏肾脏等的影响,还介绍了钒与癌症、白内障、骨与牙齿等疾病关系,最后叙述了钒的中毒及其防治的有关情况.     

微量元素钡在动物体内的生物学作用

钒是动物体内的必需微量元素。本文概要介绍了近20年来有关钒的生物学作用的研究。目前的研究表明,钒对生长发育、心血管、造血功能、肾脏及代谢均有重要影响,另一方面,钒对动物体内具有一定的毒性。     

钒对肉用鸡血液抗氧化功能的影响

用150只1日龄AA肉鸡为动物模型，随机分为5个组，每组30只，每组3个重复，动态研究了日粮中不含量钒对肉用鸡血液氧自由基含量本底值、氧自由基含量峰值、血液主要抗氧化酶（SOD、GSH-Px及CAT)活性及脂质过氧化终末代谢产物丙二醛（MDA）含量的影响。结果表明，在常规饲料0.56678mg/kg钒）中添加1.0mg/kg钒对氧自由基代谢和抗氧化功能无促进作用；添加4.0mg/kg钒试验期45d后和添加16、64mg/kg钒可使肉用鸡血液氧自由基代谢紊乱，抗氧化功能受到损伤。     

铬在畜禽中的应用研究进展

阐述了铬营养素的动物生理学功能，介绍了铬的营养代谢及其在奶牛、鱼、猪、肉鸡等畜禽生产中应用研究进展，提出了动物补铬的依据和营养研究方向。     

茶园生态系统服务功能

茶园生态系统是农业生态系统的组成之一，茶树及其间作植物与环境既有矛盾的一面，又有统一的一面，两者构成一个有机的整体。生物体必须与它的环境条件相适应才能生存和发展这一基本原理，无论自然生态系统或茶园生态系统都是一致的。人们认识到，茶园生态系统不仅向人类提供茶叶、其他的一些副产品，如水果、蔬菜、药材和家禽、家畜等，更重要的是它也维持了地球生命支持系统，即涵养水源、改良土壤、防止水土流失、减轻自然灾害、调节气候、净化环境、孕育和保存生物多样性等功能，以及具有观赏园林价值、展示传统文化、旅游休憩等社会功能。文中论述了茶园的生态服务功能、经济服务功能、社会服务功能。     

肥胖基因及其产物的研究进展

Ob基因编码的Leptin具有降低脂肪，维持能量平衡，调节代谢、生殖、激素分泌，提高免疫机能等多方面的功能。本文在介绍Leptin、Leptin受体的基础上进一步对Leptin的生物学功能及其作用机制、Leptin的抗性做一简要论述，并提出了Leptin今后的研究方向及其在畜牧业上的应用前景。     

微量元素钒在动物体内的生物学作用

钒是动物体内的必需微量元素。本文概要介绍了近20年来有关钒的生物学作用的研究。目前的研究表明,钒对生长发育、心血管、造血功能、肾脏及代谢均有重要影响,另一方面,钒对动物体内具有一定的毒性。     

多不饱和脂肪酸的营养功能及其在家禽生产中的应用

多不饱和脂肪酸是一类具有重要生物学功能的物质，主要包括n-3和n-6系列多不饱和脂肪酸，它们对脂类的代谢，机体的免疫，血液生化特性的影响，机体的生长发育及细胞膜功能的发挥和基因表达调控等许多方面起着重要的作用，本文主要介绍了多不饱和脂肪酸的营养功能及其作用的机理，并就其在家禽生产中的应用作一综述。     

新型的饲料添加剂硫辛酸

硫辛酸又称二硫辛酸，近年来已经成为最受关注的强抗氧化剂。主要介绍了硫辛酸的性质、分布、生物学功能及其应用方面。     

牛至油及其在养猪业上的应用

作者介绍了新型饲料添加剂牛至油的主要化学成分、理化特性、功能及其在养猪业上的应用，旨在为我国养猪业的持续健康发展提供参考。     

The public health implications of farming cattle in areas with high background concentrations of vanadium

Forty-two adult Brahman-cross cattle farmed extensively in two groups, immediately adjacent to and 2 km from a vanadium processing plant respectively, were slaughtered over a 5 year period at a nearby abattoir. Cattle were being exposed to vanadium at close to no-adverse-effect levels. The dose of vanadium that cattle were taking in prior to slaughter was calculated for each animal from environmental and physiological data using a stochastic risk assessment model. The median exposure doses in the month prior to slaughter ranged from 0.55 to 2.73 mg vanadium/kg body weight/day. A range of tissues was taken from the cattle at slaughter for vanadium determination and tissue levels of vanadium in muscle, liver and kidney are reported. The concentrations of vanadium in the milk of cattle from the same farm sampled over 5 years are also reported. Concentrations were further modelled using a lognormal distribution function to look at possible extreme values that are likely to occur. The concentrations of vanadium in commonly consumed tissues ranged from <0.05 to 11.51 mg/kg (wet-mass basis). The median concentration of vanadium in milk was 0.23 mg vanadium/kg. People drinking milk were at highest risk. The potential oral daily intake of vanadium for people consuming these foodstuffs was modelled using a stochastic model. The model predicted that there is less than a 5% chance that the potential daily intake of vanadium from milk will be >0.44 μg/kg/day for adults. Based on this upper limit it was concluded from current knowledge of toxicity in humans that the tissue and milk residues from cattle should pose no health risk to the consumer.     

卵磷脂的生物学功能及其应用

近年来,卵磷脂的生物学功能越来越受到人们的关注,其在调节代谢、增强体能、强化脑部功能、调节血脂等方面具有较好的功效,在多个领域有着广泛的应用。主要综述了卵磷脂的生物功能及其应用的领域,以便人们更深入地了解卵磷脂。     

Chronic Vanadium Poisoning in Calves and Its Treatment with Calcium Disodium Ethylenediaminetetraacetate

Sixteen Friesland heifer calves aged between 96 and 157 days were removed from a dairy farm that had been polluted with vanadium and randomly allocated into two equal groups (n = 8). The objective of the trial was to determine whether calcium disodium ethylenediaminetetraacetate (CaNa₂EDTA) could be used as a treatment for cattle running in environments high in background vanadium. The treatment group received 80 mg CaNa₂EDTA per kg body weight intraperitonealy (i.p.) twice a week over a 10-week period. The control group received normal saline i.p. over the same period. During the trial calves were exposed to a daily intake of vanadium in the form of contaminated tef hay derived from the farm of origin. In addition, the total mixed ration was spiked with a further 20 mg V₂O₅/kg feed to compensate for possible on-farm inhalation exposure. A stochastic model was used to estimate daily intake of vanadium as a distribution function. The model estimated that the daily intake of vanadium varied between an absolute minimum of 33 mg/day to an absolute maximum of 124 mg/day. The average intake of vanadium was 71.8 mg per day per calf. Various chemical pathology parameters were measured throughout the trial as well as urine excretion rates of vanadium and lymphocyte stimulation counts. All calves were slaughtered and necropsied in cohorts of 4–6 animals at monthly intervals after completion of the trial and withdrawal of vanadium from the ration. Tissue concentrations of vanadium were determined and necropsy findings were noted. The study found that CaNa₂EDTA appears to enhance the excretion of vanadium in calves, but could not prove that the treatment had a protective effect against vanadium exposure. Calves were able to tolerate the prolonged treatment with CaNa₂EDTA without side-effects.     

家禽miRNA研究进展简

microRNA（miRNA）是近年来研究较为广泛的一种短小RNA,主要功能是调节与个体生长、发育、疾病发生过程有关基因的表达,参与生命过程中一系列重要进程,包括早期发育、细胞增殖、细胞凋亡、脂肪代谢、细胞分化等。作者主要概述了家禽miRNA对胚胎发育、性腺发育、肌肉生长、脂肪代谢的调控作用,并对家禽miRNA的研究前景进行了简单探讨,以期为下一步开展相关研究提供参考。     

多不饱和脂肪酸对种公鸡繁殖性能的影响及其作用机理

多不饱和脂肪酸(PUFA)是一种具有重要生物功能的脂类物质,除可提供能量外,还对动物的免疫功能、机体代谢和繁殖性能等具有调节作用。本文简述了PUFA对种公鸡繁殖性能的影响及其作用机理,为合理利用家禽饲粮中油脂资源和提高家禽良种产业经济效益提供理论参考。     

甜菜碱的生理学功能及其在畜牧生产中应用的研究进展简

甜菜碱及其盐酸盐作为一种高活性的甲基供体,在甲基代谢中起着重要的营养调控作用,同时具有调节体内渗透压、促进脂肪与氨基酸代谢、增强蛋白质合成和改善肉品质等重要作用,故甜菜碱作为一种新型、安全的营养性添加剂在饲料工业和动物生产中得到了越来越广泛的应用。作者综合近年来国内外有关甜菜碱的文献报道,就其生理学功能及其在畜牧生产中的应用进行综述。     

禽胰液分泌的调节

综述近年来对家禽胰液分泌的研究进展.胰液含有多种消化酶,在家禽对饲料的消化中起重要作用,是研究动物消化代谢的主题之一.     

ADIPOQ基因调控猪脂肪沉积的研究进展

ADIPOQ是到目前为止人们所知唯一与肥胖呈负相关的激素,其可参与动物机体对葡萄糖代谢和脂肪沉积的调控。文章就ADIPOQ基因的基因结构,生物学功能和多态性及在不同猪种间的表达量进行了介绍,综述了ADIPOQ基因调控猪脂肪沉积的研究进展。     

益生素与机体免疫作用研究进展

益生素作为一种绿色饲料添加剂已广泛应用于畜牧生产中。由于其具有维持肠道菌群平衡、调节机体免疫、改善机体代谢、净化肠道环境等多方面的作用，且在使用过程中无毒副作用、无药物残留、不产生耐药性，因此已成为抗生素的理想替代品。文章从益生素在维持肠道天然屏障功能、加速肠道损伤上皮的修复和增强机体非特异性与特异性免疫应答等几个方面综述了其在调节机体免疫方面的研究进展。