生物素在畜禽养殖中的应用

<正> 1.生物素(维生素H)的生理作用生物素是构成哺乳动物体内许多酶的要素,如乙酰辅酶A羧化酶,丙酮酸羧化酶,丙酰辅酶A羧化酶和β-甲基丁烯酰辅酶A羧化酶。生物素通过以上酶系参与下述三大营养代谢的调节。一是对脂类代谢的调节。     

生物素(V_H)对猪的营养作用

一、生物素的功能生物素(V_B)对动物的正常生长,骨和软骨的发育,维持上皮组织的健康,提高繁殖机能及饲料利用效率,都起着重要作用。虽然对生物素在动物体内生化反应的研究较少,但已经知道猪的内部器官富含丙酮酸羧化酶、乙酰辅酶A羧化酶、β-甲基巴豆醇辅酶A羧化酶、丙酰辅酶A羧化酶等生物素酶,     

生物素对畜禽营养生理作用及免疫机理的研究进展

生物素作为羧化、脱羧和脱氢反应酶系的辅助因子,是丙酮酸羧化酶、乙酰辅酶A羧化酶、丙酰辅酶A羧化酶和β甲基丁烯酰辅酶A羧化酶的羧基载体,在碳水化合物、脂类、蛋白质和核酸的代谢过程中必不可少。本文就对生物素对畜禽营养生理作用及免疫机理的研究进行了综述。     

生物素的免疫功能研究进展

生物素作为羧化、脱羧和脱氢反应酶系的辅助因子，是丙酮酸羧化酶、乙酰辅酶A羧化酶、丙酰辅酶A羧化酶和D-甲基丁烯酰辅酶A羧化酶的羧基载体，在碳水化合物、脂类、蛋白质和核酸的代谢过程中必不可少。愈来愈多的研究表明，生物素不仅是动物正常生理活动的必需酶的辅助因子，还对免疫机能有影响。该文就生物素的生理功能及其对免疫机能影响的研究进展做了概述。     

生物素的生理功能及其分子作用机制

生物素是动物机体内维持正常生理机能所必需的一种维生素。它作为4种羧化酶辅酶成分,在哺乳动物体内的葡萄糖、氨基酸和脂肪酸代谢中起着重要作用。越来越多的研究表明,生物素对基因表达的调控起着重要的作用。本文综述了生物素的营养生理作用及其对基因表达调控的影响。     

生物素在家禽营养中的作用

生物素是一种白色晶体化合物,是各种酶在羧化反应中的辅助因子。它含有两种最重要的酶,促进糖元异生过程的丙酮酸羧化酶和促进脂肪合成的乙酰辅酶A羧化酶。生物素最本质作用是既能促进糖和脂肪的新陈代谢,又能影响蛋白质的合成及核糖核酸的性质和比例。生物素虽然是日粮中的微量元素,但是对鸡的影响却非     

生物素的营养代谢调控及生理功能研究进展

生物素是一种水溶性含硫维生素,在动物体内具有重要的生理功能。其作为4种羧化酶的辅酶成分,在催化糖原异生、氨基酸分解代谢和脂肪酸合成中起关键作用。随着分子生物技术的发展应用,人们发现生物素还能影响转录和翻译水平基因的表达,参与有关营养代谢的调控。文章综述了生物素的营养代谢调控及生理功能。     

生物素在家禽营养中的作用

引言纯生物素是一种白色晶体化合物,微溶于水和乙醇而不溶于其他有机溶剂。中等度耐热,耐弱酸、弱碱,易被强酸强碱破坏。生物对于畜禽的重要性,在于它是与羧化反应有关的各种酶的一种辅助因子。这里最重要的是促进糖元异生过程的丙酮酸羧化酶和促进脂肪合成的乙酰辅酶A羧化酶。因此,生物素在糖和脂肪的代谢中起着必不可少的作用。生物素还通过其对     

吡啶羧酸铬对肉仔鸡血清生化指标及肝脏中相关酶基因表达的影响

试验研究了4～6周龄肉仔鸡日粮中添加1mg/kg吡啶羧酸铬后,其血清总甘油三酯、总胆固醇、高密度脂蛋白、低密度脂蛋白和极低密度脂蛋白的变化,及其对肝脏中脂肪酸合成酶、乙酰辅酶A羧化酶、β-羟甲基戊二酰辅酶A还原酶基因转录的影响。其中总甘油三酯、总胆固醇、低密度脂蛋白和极低密度脂蛋白均有下降的趋势,而高密度脂蛋白有上升的趋势,但是差异均不显著(P>0 05)。运用RT-PCR定量三种基因的mRNA,结果表明添加铬后脂肪酸合成酶和β-羟甲基戊二酰辅酶A还原酶的转录明显受到影响,分别比对照组下降34 82%和48 26%,而乙酰辅酶A羧化酶受影响很小,其转录只下降了3 87%。     

兽药安全使用常识

1.什么是生物素?其主要作用及临床应用是怎样的?①生物素(Biotin),又叫维生素H、维生素B和辅酶R,是一种含硫维生素。生物素参与机体碳水化合物代谢;生物素酶能催化脱羧和羧化反应。特别是在饲料中碳水化合物不足时,生物素可通过蛋白质和脂肪的葡萄糖异生作用维持血糖的稳定。生物素参与机体的脂类代谢;生物素缺乏降低动物从亚油酸合成花生四烯酸的能力,导致亚油酸在体内的积累。生物素参与机体蛋白质和核酸的代谢;在蛋白质合成氨基酸、脱氨、嘌呤的合成,氨基甲酰转移,以及亮氨酸、色氨酸分解代谢,起重要作用。参与其他物质的代谢作用。     

中国饲料工业协会第五届理事会顾问、会长、常务副会长、副会长、秘书长、副秘书长、常务理事、理事名单

顾问刘中一张德邻宋瑞祥聂振邦张子仪戎易王维四会长白美清国务院原副秘书长、第四届理事会会长常务副会长(8人,以姓氏笔划为序)刘永好新希望集团董事长、第四届理事会副会长刘汉元通威股份有限公司董事长、第四届理事会副会长陈丹广东恒兴集团股份有限公司董事长、第四届理事会副会长张延喜农业部原副部长、第四届理事会副会长吴明夏湖南正虹科技发展股份有限公司董事长、第四届理事会副会长陶一山唐人神集团股份有限公司董事长、第四届理事会副会长温鹏程广东温氏食品集团有限公司董事长、第四届理事会副会长谭竹洲原化学工业部副部长、第…     

Evidence for the non-involvement of the uterus in the lifespan of the corpus luteum in the cyclic dog

Progesterone levels in peripheral blood of dogs were analysed during the cycle in which hysterectomy (n = 5) or sham surgery (n = 3) was performed as well as during the cycle of dogs (n = 5) hysterectomized at least one year prior to this study; the data were compared with the findings in control dogs (n = 3). The averages of the duration of the luteal period observed in the three experimental groups were not significantly different from those of control dogs. Immediately after surgery, the progesterone level decreased from 25 to 50% of the presurgical level, but returned to presurgical level in about four days. Prolactin levels were elevated for about 30 h after surgery. Nevertheless, the averages of the mean prolactin levels for each animal during the luteal period of the experimental groups were not significantly different from those of control dogs. It is concluded that in the dog, the uterus is not involved in the lifespan of the cyclic corpus luteum.     

浅谈对症用药

对症用药就是通过对患病信鸽的症状进行诊断,进而确定病属,选择药物及如何用药的方法。     

军犬鉴别中的嗅源培养和易出现的问题及对策

嗅源是军犬嗅觉作业训练的依据.军犬鉴别中嗅源能力的培养在整个鉴别训练中占有重要地位,关系到鉴别训练的成败和鉴别能力的提高.所以,军犬在嗅认嗅源时必须按照训犬员的指令充分、细致地感受嗅源气味,并且对嗅源气味产生兴奋反应.如何培养军犬充分嗅认嗅源以及及时解决嗅认过程中出现的问题,成为我们进行鉴别训练的关键.……     

The influence of the width of the saddle tree on the forces and the pressure distribution under the saddle

As there is no statistical evidence that saddle fit influences the load exerted on a horse's back, this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was determined. Saddles were classified as "too-narrow" if they were one size (2 cm) narrower than the LOF saddle, and "too-wide" if they were one size (2 cm) wider than the LOF saddle. Saddles two sizes wider than LOF saddles were classified as "very-wide". In the group of narrow saddles, the pressure in the caudal third (walk 0.63 N/cm(2)+/-0.10; trot 1.08 N/cm(2)+/-0.26) was significantly higher compared to the LOF saddles (walk 0.50 N/cm(2)+/-0.09; trot 0.86 N/cm(2)+/-0.28). In the middle transversal third, the pressure of the wide saddles (walk 0.73 N/cm(2)+/-0.06; trot 1.52 N/cm(2)+/-0.19) and very-wide saddles (walk 0.77 N/cm(2)+/-0.06; trot 1.57 N/cm(2)+/-0.19) was significantly higher compared to LOF saddles (walk 0.65 N/cm(2)+/-0.10/ 0.63 N/cm(2)+/-0.11; trot 1.33 N/cm(2)+/-0.22/1.27 N/cm(2)+/-0.20). This study demonstrates that the load under poorly fitting saddles is distributed over a smaller area than under properly fitting saddles, leading to potentially harmful pressures peaks.