磷脂在猪饲料中的应用

磷脂广泛存在于自然界中,是生物膜的基本组成部分,在生物生命过程中起代谢和结构形成作用,近年来因其重要的生理功能广泛的应用在食品、药品、饲料等行业中。文章综述了磷脂在猪饲料中的应用,通过分析磷脂饲料在提供营养、改善体脂构成、提高饲料转化率、提高幼体成活率等方面的作用,对磷脂在猪饲料中的应用前景进行展望,以期为磷脂饲料的研究与开发奠定基础。     

磷脂的生理功能及其应用

1磷脂的生理功能 磷脂有调整生物膜的功能。生物膜对于动物具有重要的生理功能，控制着细胞的新陈代谢、细胞问的热量生成与转移、信息传导、对外部侵害的抵御能力以及细胞的修复能力。磷脂有促进脂类代谓十和转运，保证血管的通畅及正常肝脏功能。表面活性磷脂能有效保护胃黏膜不受损伤。动物体内许多生化代谢活动都离不开酶的参与，     

哪些奶牛疾病应该补磷

正磷是所有矿物质中生物功能最多的元素。第一,与钙一起参与骨骼和牙齿结构的组成,保证骨骼和牙齿的结构完整。第二,参与体内能量代谢,是三磷酸腺苷和磷酸肌酸的组成部分。第三,促进营养物质的吸收,磷以磷脂的方式促进脂类物质和脂溶性维生素的吸收。第四,保证生物膜的完整,磷脂是细胞膜不可缺少的成分。第五,磷作为重要生命遗传物质脱氧     

低磷奶牛红细胞膜冰冻蚀刻电子显微镜观察

磷是动物必需的重要元素.它是生物膜磷脂的基本组分,红细胞膜磷脂含量超过60%.磷的缺乏可引起动物许多组织器官损伤.     

大豆磷脂在动物生产中的应用

大豆磷脂产品的主要成分有油脂、磷脂、胆碱、不饱和脂肪酸和维生素E等。磷脂是生物膜的重要组成部分,是动物脑、神经组织、骨髓和内脏中不可缺少的组成部分,对幼龄动物的生长发育非常重要。     

虾类对脂类的营养需求及其利用机理的研究

脂类是虾类生长发育过程中所必需的能量物质,它可提供虾类生长所需的必需脂肪酸、胆固醇及磷脂等营养物质。饵料中脂肪酸按碳与碳之间有无双键分为饱和和不饱和脂肪酸;按照水产动物需求程度又可分为必需脂肪酸和非必需脂肪酸。必需脂肪酸在水产动物体内不能通过体内合成得到,必须通过饵料供给,必需脂肪酸是生物膜磷脂的组成成分和合成具有多种代谢功能的二十烷酸类化合物(ｅｉｃｏｓａｎｏｉｄｓ)的前体,生物膜的流动性取决于生物膜磷脂中饱和和不饱和脂肪酸的平衡(Ｂｅｌｌ等1986)。1　脂类对虾类的营养机理及其缺乏症状11　脂类在虾类营养…     

磷脂与水生动物生物膜的关系

近年研究发现,水生动物对磷脂的合成能力有限。磷脂可以促进动物生长、提高存活率(Kanazawa等,1981),促进甘油三酯、胆固醇和一些脂溶性营养物质的吸收与转运(Geurden等,1998),磷脂也作为生物膜脂质的主要成分,影响细胞功能,参与细胞信号转导(Malaquias和Oliveira,1999),发挥着     

磷脂与水生动物生物膜的关系

近年研究发现，水生动物对磷脂的合成能力有限。磷脂可以促进动物生长、提高存活率（Kanazawa等，1981），促进甘油三酯、胆固醇和一些脂溶性营养物质的吸收与转运（Geurden等，1998），磷脂也作为生物膜脂质的主要成分，影响细胞功能，参与细胞信号转导（Malaquias和O-liveira，1999），发挥着重要作用。     

大豆磷脂在水产饲料中的应用

磷脂是动物神经系统、骨髓、心、肝和脾不可缺少的组成部分,是生物膜的重要组成,添加磷脂能促进鱼类的脑、神经组织、内脏、骨髓的发育健全,还可以节约蛋氨酸的消耗,提高饲料质量。鱼类在孵化后的快速生长中,需要丰富的磷脂来构成细胞的成分,当磷脂的生物合成不能充分满足仔鱼的需求时,便需要在饲料中添加磷脂。磷脂可以提供鱼类自身无法合成的亚麻酸和亚油酸,还能促进甲壳动物对胆固醇的利用,提高甲壳动物的生长、脱壳和成活率。本文综合国内70年代至今的文献,总结了大豆磷脂饲料对鱼和甲壳类动物中的作用。     

磷对奶牛生产性能的发挥至关重要

1磷的功能
　　磷是所有矿物质中生物功能最多的元素。其功能主要表现在：（1）与钙一起参与骨骼和牙齿结构的组成，保证骨骼和牙齿的结构完整；（2）参与体内能量代谢，是ATP和磷酸肌酸的组成部分；（3）促进营养物质的吸收，磷以磷脂的方式促进脂类物质和脂溶性纤维素的吸收；（4）保证生物膜的完整，磷脂是细胞膜不可缺少的成分；（5）磷作为重要生命遗传物质，参与生命活动过程，如蛋白质合成和动物产品生产。磷对奶牛生产性能的发挥至关重要。     

氧自由基与细胞损伤

氧自由基导致细胞的损伤机制在某些疾病的发病机理中具有重要作用，氧自由基损伤主要机制之一就是触发细胞膜上不饱合脂肪酸发生胆质过氧化链式反应，使内质网、溶酶体，线粒体等生物膜结构破坏，导致一系列功能紊乱，本文主要从这一损伤机制出发，综述了近年来氧自由基对肝脏，肾脏，内皮及其它一些脏器细胞损伤机理研究进展。     

奶牛氧化应激研究进展

高产奶牛更容易发生氧化应激,氧化应激可以导致生物学大分子和生物膜系统的破坏,并可以增加炎症反应时的组织损伤：奶牛氧化应激的产生除了与机体的生理状态、健康状况和饲料成分有关外,环境因素也会引起氧化应激。目前主要通过饲喂抗氧化添加剂来预防奶牛氧化应激。     

铜在动物体内代谢的研究进展

铜是人类和动物体内重要的微量元素之一,它不仅参与机体内蛋白质、氨基酸、核酸、脂肪、碳水化合物、维生素等营养物质代谢,而且还在骨骼发育、生殖、免疫、凝血、生物膜的稳定性等生理机能中起着重要作用。本文综述了近年来铜在动物体内的吸收、转运、分布及排泄的研究进展,认为铜代谢及其平衡机制应予以深入研究。     

Surgical treatment of severe pulmonic stenosis under cardiopulmonary bypass in small dogs

Objectives : The aim of this study was to report the long‐term outcome of the surgical palliation of pulmonic stenosis in dogs. Methods : The subjects comprised three female and six male dogs, mean (±sd) age: 23 (±25) months, mean (±sd) weight: 3·4 (±2·1) kg, diagnosed with severe pulmonic stenosis and right ventricular hypertrophy, with an average preoperative pressure gradient of 153 (±43) mmHg on echocardiography. Results : The pressure overload with severe pulmonic stenosis was reduced by valvotomy, i.e., open pulmonary valve commissurotomy, with/without biomembrane patch grafting, under cardiopulmonary bypass. The postoperative pressure gradient at 1 to 7 days was significantly decreased to 65 (±39) mmHg (P<0·05). The reduced pressure gradient was maintained at 58 (±38) mmHg at final follow‐up. Clinical Significance : Open valvotomy, pulmonary valve commissurotomy and biomembrane patch grafting were effective in reducing obstruction in severe pulmonic stenosis in dogs.     

脱落酸（ABA）对白三叶抗旱作用机理的初步研究

本文就不同浓度ＡＢＡ对干旱胁迫条件下白三叶植株功能叶片抗旱生理指标进行了研究，结果表明，ＡＢＡ能明显减少叶片水分蒸发，降低叶片细胞膜透性，增加叶片细胞可溶性蛋白质含量，诱导生物膜系统保护酶ＳＯＤ形成，从所测生理结果及复水前后白三叶生长状况来看，ＡＢＡ最佳抗旱处理浓度为７５ｍｇ／ｋｇ。     

母乳磷脂与婴幼儿配方乳粉开发研究进展

母乳是婴儿最完美的营养来源,含有婴儿生长发育所需的所有营养物质.磷脂具有促进婴儿肠道、大脑及认知发育等作用,对婴幼儿健康发育非常重要.本文对母乳磷脂进行介绍,重点阐述现有文献资料中不同国家/地区母乳中磷脂的组成及含量差异,并对比分析母乳磷脂组成与磷脂脂肪酸组成与牛乳、山羊乳和绵羊乳存在的差异.旨在为婴幼儿配方乳粉的开发...     

Mitochondrial phospholipids of rat skeletal muscle are less polyunsaturated than whole tissue phospholipids: implications for protection against oxidative stress

The fatty acid composition of phospholipids is an important determinant of membrane function. Although the mitochondria play a pivotal role in skeletal muscle function, the fatty acid composition of their individual phospholipids has not been examined. The purpose of this study was to determine the fatty acid profile of each phospholipid in rat skeletal muscle mitochondria and compare it with that of the whole muscle. Lipids were extracted from the gastrocnemius muscles of 10 Wistar rats, and phospholipids were separated by thin-layer chromatography. The fatty acid composition of each phospholipid was then determined by gas chromatography. The same procedure was applied to a mitochondrial preparation from these muscles. We found that the fatty acid composition of the individual mitochondrial phospholipids (phosphatidyl choline, phosphatidyl ethanolamine, cardiolipin, phosphatidyl inositol, phosphatidyl serine, sphingomyelin, and lysophosphatidyl choline) and of the total mitochondrial phospholipids differed markedly (P < 0.05) from the fatty acid composition of the corresponding whole muscle phospholipids. Notably, the mitochondrial phospholipids had higher percentages of MUFA [13.9 (2.1) vs. 10.3 (0.9)] and lower percentages of PUFA [34.8 (4.3) vs. 39.5 (5.2)] and n6 fatty acids [25.0 (2.5) vs. 27.6 (2.5)]. Overall, the mitochondrial phospholipids had a lower unsaturation index than whole muscle phospholipids [135 (20) vs. 161 (26)]. Because PUFA are susceptible to peroxidation, unlike saturated fatty acids and MUFA, we propose that the low polyunsaturation of mitochondrial phospholipids is the result of selective pressure toward membranes that are more resistant to oxidative damage by reactive oxygen species produced in their vicinity. The negative effect of the low polyunsaturation on membrane fluidity may be counterbalanced by the higher percentage of MUFA and the known low cholesterol content of mitochondrial membranes.     

内蒙古绒山羊精液冷冻过程中胆固醇、磷脂变化的研究

冷冻精液受胎率的高低易受多因素的影响,其中顶体异常率较高可能是因素之一。精子磷脂和胆固醇可能与稀释液中的磷脂和胆固醇发生部分交换而导致精子中的胆固醇降低,致使精子提前获能甚至部分发生顶体反应。系统地分析了山羊精液冷冻过程中每个处理磷脂、胆固醇含量的变化。     

Ultrastructure of the hydrophobic gastric surfactant barrier in the dog

OBJECTIVES: To confirm the hydrophobicity of the luminal surface of the canine stomach and to elucidate the ultrastructure of the lining imparting that property. DESIGN AND PROCEDURES: Gastric and duodenal mucosal samples from eight dogs were collected immediately after euthanasia and subjected to contact angle measurement using a goniometer. Other samples were examined by electron microscopy following a fixation procedure known to preserve phospholipids and oligolamellar structures. RESULTS: Contact angles for the canine gastric mucosal surface (85.1 +/- 5.5) were significantly greater (P < 0.0001) than for the duodenum (24.0 +/- 1.7). Electron microscopy revealed the existence of surfactant as abundant osmiophilic phospholipid material within the gastric and duodenal mucosae. CONCLUSION: We have confirmed the hydrophobic nature of the canine gastric mucosa whereas the luminal surface of the duodenum is hydrophilic. We propose that the water-repellent nature of the canine gastric lining contributes to the 'gastric mucosal barrier' and is imparted by an oligolamellar layer of surface-active phospholipid ('gastric surfactant') adsorbed to the surface. Both gastric and duodenal mucosae may also utilise phospholipids as an intercellular defense mechanism in the event that tight junctions are breached by acid. It is tempting to speculate that a deficiency of gastric phospholipids may predispose dogs to ulcers. Further, exogenous administration of phospholipids may be useful in preventing gastric ulceration.