Amino acid interactions in chick nutrition. 2. Interrelationships between leucine, isoleucine and valine

The nature of interactions between leucine, isoleucine and valine has been examined in the young chick. In a preliminary experiment excess leucine was added to a diet limiting in isoleucine. The consequent growth depression was partially reversed by additional isoleucine. The plasma amino acid data indicated that the circulating levels of isoleucine and valine were lowered by the surplus load of leucine. Addition of excess leucine to another diet prevented the growth response to the first limiting amino acid, methionine, but permitted the response if this diet were adequately supplemented with isoleucine. Another diet was prepared in which the level of isoleucine was limiting and the level of valine marginally adequate. The growth retardations following addition of large quantities of leucine were reversed primarily by valine. Complete restoration of growth occurred when both valine and isoleucine were present as additional supplements. Excess methionine added to a diet limiting in valine inhibited growth severely but reversal did not occur following valine supplementation.

The results establish the existence of specific interactions between leucine‐isoleucine and leucine‐valine which account adequately for the adverse effects of leucine. Of these interactions, that between leucine and valine appears to be nutritionally more significant. The results are discussed in the light of the concept of agent and target.     

Amino acid interactions in chick nutrition. 3. Interdependence in amino acid requirements

The quantitative nature of specific interactions between certain indispensable amino acids has been examined in a series of factorial experiments with young chicks.

It was demonstrated that when the dietary concentration of lysine was 1.10 per cent, the arginine requirement of the chick was 0.80 per cent. When the lysine concentration was raised to 1.35, 1.60 or 1.85 per cent of the diet, the arginine requirement was increased to 0.92, 1.04 and 1.15 per cent of the diet respectively. In another experiment, it was found that when due importance had been attached to the interaction between lysine and arginine, the requirements for these amino acids could be lowered to 0.94 per cent and 0.81 per cent respectively. These concentrations are considerably lower than those normally recommended for young chicks.

The interrelationship between leucine and isoleucine has also been defined in quantitative terms. At concentrations of 1.40, 2.15 or 2.90 per cent leucine, the isoleucine requirement was 0.58, 0.62 and 0.65 per cent of the diet respectively.

In a further study, a similar dependence of valine requirements upon the dietary concentration of leucine was observed: at concentrations of 1.40, 2.40 or 3.40 per cent leucine, the valine requirement was shown to be 0.77, 0.89 and 1.01 per cent respectively. The results of the experiment on the threonine‐tryptophan interaction indicated that at concentrations of 0.80, 1.30, 1.80 or 2.30 per cent threonine, the tryptophan requirement was 0.17, 0.18, 0.19 and 0.20 per cent of the diet respectively.

The results of the present study permit the general conclusion that the requirements of amino acids are interdependent.     

Amino acid interactions in chick nutrition. 4. Growth, food intake and plasma amino acid patterns

A series of experiments has been conducted with chicks to study the effects of excess lysine, leucine and incomplete mixtures of amino acids on growth, food intake and plasma amino acid patterns.

Excess lysine induced a marked depression in growth within 48 h. Towards the end of the experiment, the chicks lost weight and showed no signs of adaptation to the excess dose of lysine. The plasma concentration of arginine fell within 24 h of feeding excess lysine but the reduction in food intake did not occur until 6 d of the experiment had elapsed. Excess leucine similarly caused a rapid retardation of growth which was followed subsequently by a depression in food intake. Mixtures of amino acids lacking in leucine, isoleucine and valine also induced marked growth inhibitions the severity of which were enhanced by the inclusion of leucine and isoleucine in the mixtures. Growth tended to be adaptive in chicks fed on the incomplete amino acid mixtures but non‐adaptive in those fed on excess leucine.

Pair‐feeding studies indicated that appreciable differences in weight gain still occurred when food intake was equated between control groups and groups receiving excess lysine or leucine.

The results of the present study indicate that the depression in food intake cannot account completely for the ill‐effects of excess lysine and leucine. They also suggest that the adverse effects of lysine and leucine are distinct from those caused by incomplete mixtures of amino acids.     

Amino acid requirements of the young turkey: lysine and arginine.

The arginine and lysine requirements for maximum growth of the 3-week-old turkey, determined in a factorial manner, were 1-75% arginine and 1-55% lysine. 2. It is demonstrated that the arginine required to support a growth rate of about 20 g/d is similar in turkeys and chicks, suggesting that the efficiency with which dietary arginine was utilised for growth is similar in both species.     

动物营养中赖氨酸与精氨酸互作关系的研究进展

赖氨酸和精氨酸是对多数动物维持生长和氮平衡等具有重要作用的氨基酸。二者在动物的蛋白质合成、能量贮存、促进淋巴细胞转化、增强动物的免疫功能和氮代谢产物排泄等方面都有十分重要的功能。对于不同动物,饲料中不同的赖氨酸和精氨酸比例与动物的生长有很大关系。本文综述了赖氨酸和精氨酸在动物营养中互作及其二者适宜比例的研究进展。     

Amino acid nutrition in egg production industry

The egg production industry is facing various problems that need to be solved. For amino acid nutrition to achieve scientific and economical feeding of laying hens, it is necessary to elucidate the content, digestibility, or availability of nutrients of feedstuffs and feeds and the requirement of amino acids for laying hens. In addition, improvement to quality of eggs and meat of spent hens, methods of management and development of new feedstuffs are essential. For sustainable animal production, decrease in excreta and animal welfare should be studied. The real‐time determination of content and digestibility of amino acids in feedstuffs are essential for formation of feeds. Recent advances in the near infrared reflectance analysis will be able to determine the content, digestibility and availability of nutrients in feedstuffs and feeds, if we have a supplemental amount of conventional analysis to define the calibration population. The amino acid requirements are affected by various factors. Therefore the method to quickly and exactly determine amino acid requirements in response to various factors is necessary. By using plasma free amino acid concentration as a criterion, it is possible to determine amino acid requirements in various conditions of laying hens within a short experimental period, repeatedly using the same animals. Because the amino acid requirements differ among individual animals, it should be expressed as grams per hen per day. Practically, it is impossible to formulate various feeds for individual hens. The various expressions have been developed and these expressions have advantages and disadvantages. The nitrogen excretion of laying hens is easily reduced by reducing dietary nitrogen levels and restricting the feed intake. The availability of amino acid may be improved by feeding management, and supplementing enzyme, but the quality of eggs and meat of spent hens and welfare of laying hens are not affected by amino acid nutrition.     

Arsenic-sulfur amino acid interactions in the chick

Experiments were conducted with growing crossbred chicks to determine the reasons why cysteine exacerbates roxarsone (3-nitro-4-hydroxyphenylarsonic acid) toxicity. A fortified corn-soybean meal diet that met or exceeded all nutrient requirements of the young chick was fed. While cysteine enhanced roxarsone toxicity, it had little effect on the toxicity of the inorganic arsenicals As2O3 and As2O5. The toxicity of another pentavalent organic arsenical, phenylarsonic acid, was also exacerbated by cysteine. In contrast, the growth-depression resulting from feeding the trivalent form of phenylarsonic acid, i.e., phenylarsine oxide, was not affected by dietary addition of cysteine. Supplementation of the diet with cystine, methionine or K2SO4 did not exacerbate roxarsone toxicity. Reduced glutathione (GSH), however, slightly increased the gain/feed depression resulting from feeding 300 mg roxarsone/kg diet. When injected ip 1) roxarsone and cysteine, or 2) roxarsone and ascorbic acid killed 100 or 60% of the birds, respectively, within 48 h postinjection. Few (6.7%) deaths resulted from ip injections of the same level of roxarsone alone. Therefore, the potentiation of toxicity requires pentavalent organic arsenicals and compounds that can act as reducing agents. We concluded that cysteine exacerbates roxarsone toxicity by reducing it to the more toxic trivalent state.     

Amino acid and protein supplementation of chick diets containing single cell protein sources 1

Six samples of yeasts grown commercially on hydrocarbon oil, two bacterial protein preparations and a distillery yeast were compared in chick growth experiments of the total protein efficiency type. Various combinations of amino acids were incorporated and evaluations were also made of mixtures of the single‐cell protein sources with conventional protein foods.

When combined with cereals only, the nutritive value of the single‐cell protein sources was not influenced by amino acid supplementation to the extent expected but in the presence of a proportion of a conventional protein supplement such as fish, groundnut, soyabean or sunflower seed meal satisfactory responses were obtained. With methionine addition yeast could replace to advantage half of the total fish meal in a fish meal‐cereal diet, and two‐thirds replacement gave growth equivalent to that obtained with the all‐fish meal diet. Considerable improvements were achieved also by partially replacing each of the other types of concentrate by single‐cell protein sources.

No explanation is available at present for the failure of amino acid supplementation to improve the yeast‐cereal diets. Increasing the level of vitamins did not produce a significant effect.     

生长前期北京鸭赖氨酸与精氨酸互作关系研究

试验采用4×5双因子完全随机试验设计,研究不同赖氨酸和精氨酸水平对1～14日龄北京鸭生产性能的影响,进而探讨二者的互作关系。960只1日龄北京鸭随机分为20个处理,每个处理6个重复,每个重复8只鸭子,每个处理组分别饲喂不同赖氨酸和精氨酸水平的试验日粮。各处理组日粮中赖氨酸的总含量分别为0.50%、0.80%、1.10%、1.40%,精氨酸的总含量分别为0.65%、0.90%、1.15%、1.40%、1.65%。试验期为14 d。结果表明:日粮中不同赖氨酸和精氨酸水平对生长前期北京鸭有一定的互作效应。随日粮赖氨酸水平的升高,平均日增重、平均日采食量均表现升高的变化趋势。研究表明,1.40%赖氨酸水平组的平均日增重、平均日采食量极显著高于其他三个水平的赖氨酸处理组。随着日粮精氨酸水平的升高,北京鸭平均日增重、平均日采食量和2周平均体重均表现为先升高后降低的二次曲线变化趋势。分别以平均日增重、平均日采食量、料重比、2周平均体重为指标建立二次曲线模型,得出1～14日龄北京鸭精氨酸水平分别为0.907%、0.906%、0.946%、0.907%,根据赖氨酸/精氨酸比与生产性能关系图,得出最适赖氨酸水平为1.10%,且在...     

蛋白质、氨基酸营养与动物机体免疫机能

许多研究都已证实营养对机体免疫机能有着重要的影响 ,营养学与免疫学的交叉学科营养免疫学随着研究的不断深入而不断充实。因营养不良而导致免疫功能和机能障碍的营养性获得免疫缺乏综合症 (Ｎｕｔｒｉｔｉｏｎａｌｌｙａｃｑｕｉｒｅｄｉｍｍｕｎｅｄｅｆｉｃｉｅｎｃｙｓｙｎｄｒｏｍｅｓ：ＮＡＩＤＳ）已引起人们的普遍重视 ,对于人和动物必需的重要的营养素蛋白质和氨基酸与动物机体免疫机能的关系逐渐成为研究的重点。１蛋白质与动物机体免疫反应１.１蛋白质缺乏影响动物的免疫反应一些试验证实 ,日粮蛋白质缺乏影响动物的免疫反应。…     

仔猪的精氨酸研究与应用进展

<正>1精氨酸概述精氨酸(Arginine),分子式为C6H14N4O2,分子质量为174.2,为白色晶体或晶体状粉末。传统上一般把精氨酸定义为非必需氨基酸,但精氨酸是维持幼年动物最佳生长和氮平衡的必需氨基酸,正常情况下大部分成年哺乳动物可以自身合成精氨酸,但不足以满足机体需要,特别是在饥饿、创伤及快速生长状     

精氨酸与肠粘膜完整性的关系

一些特殊营养物质如谷氨酰胺、精氨酸、ω-3多不饱和脂肪酸、核苷酸、VA和锌等有提高机体免疫功能的作用,同时还能促进胃肠道发育,有利于粘膜损伤后的恢复,被称为胃肠道功能性食品。研究表明,肠粘膜损伤后补充精氨酸能够促进细胞的增殖、分化、成熟,抑制细胞的凋亡,有利于肠粘膜形态结构的恢复。文中对精氨酸与肠粘膜完整性的关系研究进展作一综述。     

The amino acid requirements of the growing chick. I. Determination of amino acid requirements

The amino acid requirements of the growing chick have been determined using a diet based on soybean meal and maize meal. The diet contained 18% protein (N% x 6.25, dry matter basis) made up to 14% contributed by conventional ingredients and 4% protein equivalent in the form of amino acids. Starting with a diet formulated to meet the reference levels recommended by Dean and Scott (1965) a programme of experiments was carried out to improve this amino acid balance. The results indicated that the growing chick requires not more than 0.53% threonine, 0.61% glycine, 0.79% valine, 0.62% isoleucine, 1.34% leucine, 0.75% phenylalanine (or 1.3% phenylalanine plus tyrosine), 0.85 % lysine, 0.4% histidine, 0.86% arginine, 0.17% tryptophan and 0.39% methionine (or 0.79% methionine plus cystine).     

氨基酸螯合物的研究应用

1氨基酸螯合物的概念螯合物是指一个或多个基团与一个金属离子发生配伍反应所形成的具有环状结构的化合物。一个金属元素离子可以和多个氨基酸形成环螯合物,形成的环数越多,螯合物的稳定性越好。常见的螯环有五元环(如α-氨基螯合物)和六元环(如β-氨基螯合物)。螯合物中的金属元素离子通常叫做中心离子,而与中心离子螯合着的中性分子叫做配位体,可作为中心离子的微量元素主要有铜、铁、锌、锰、铬等,使用的配位体有蛋氨酸、赖氨酸、甘氨酸等。2微量元素氨基酸螯合物的特点2.1稳定的化学性质,吸收利用率高第一代的无机微量元素添加剂由于带…     

Effects of excess arginine with and without supplemental lysine on performance, plasma amino acid concentrations and nitrogen balance of young swine

Three experiments were conducted to determine the effects of excess arginine on performance, plasma amino acid levels and N balance of young pigs (initial weights 6.9, 7.0 and 10.3 kg, respectively). In a 28-d growth trial, various amounts of arginine (0 to 1.6%) were added to a conventional starter diet. Addition of arginine decreased (P less than .01) average daily feed intake (ADFI) and gain (ADG), but had no effect on feed efficiency (G/F). Plasma urea, arginine and ornithine concentrations were elevated (P less than .001) by the increasing dietary arginine levels at d 14 and 28. Plasma histidine levels were reduced (P less than .01) at d 28. Plasma lysine levels exhibited a cubic response (P less than .05) at d 14, but were not affected by excess arginine at d 28. In a second growth trial ADFI and ADG were decreased (P less than .05), but G/F was not affected by the addition of 1.6% dietary arginine. Lysine supplementation (0, .15 or .30%) increased performance in the absence of excess arginine, but the main effect of lysine was not significant for any performance criteria. As in the first experiment, plasma concentrations of urea, arginine and ornithine were increased (P less than .001) by the addition of arginine. Plasma histidine was not affected by either arginine or lysine. Plasma lysine levels were reduced (P less than .001) by dietary arginine and increased (P less than .001) by lysine. In a N balance experiment, addition of 1.6% dietary arginine increased N digestibility, but decreased apparent biological value. Nitrogen balance was not affected by added arginine. Lysine addition did not improve any of these three indices of N utilization. The inability of lysine supplementation to alleviate any of the adverse effects of excess arginine in young swine indicates that the reduced performance is caused by a generalized amino acid imbalance, and not by a specific interference with lysine utilization in the manner of a classical arginine-lysine antagonism.     

The effect of different dietary ratios of lysine,arginine and methionine on biochemical parameters and hormone secretion in turkeys

We postulated that the use of optimal levels and proportions of Lys, Arg and Met in compound feed allows for optimal exploitation of the growth potential of contemporary slaughter turkey hybrids and reduces metabolic disorders. The aim of the study was to determine the effect of different proportions of Lys, Arg and Met in diets whose Lys content is in accordance with NRC recommendations, that is a low level, on selected parameters of protein, lipid and carbohydrate metabolism and on hormone secretion in turkeys. The lowest Arg content (90% Lys) in the diet resulted in an increase in plasma total cholesterol levels in the turkeys as compared to higher Arg content (100% or 110% of Lys), (2.50 vs. 2.09 vs. 1.83). Plasma HDL and creatinine concentration increased in turkeys fed diets with higher Arg content (100% and 110% Lys) compared to turkeys receiving the diet with the lowest Arg content (90% Lys). Compared to turkeys receiving the lowest and intermediate Arg content (90% and 100% Lys), the diet with the highest content of this AA (110% Lys) resulted in an increase in the plasma T4 level (71.21 vs. 86.60 vs. 128.2). The varied Arg and Met levels relative to Lys did not affect the secretion of neurotransmitters or hormones regulating glucose metabolism. At low levels of Met in the diet, an decrease in Arg relative to Lys from 100% to 90% caused a growth depression of turkeys (10.68 vs. 10.21 kg), which was not noted in the case of the higher Met content. When using the Lys level recommended by NRC in the turkey diet, the optimal Arg level is 100% and Met is 45% compared to Lys.     

动物营养代谢中的酸碱平衡

动物维持正常的酸碱平衡,是发挥机体细胞整体功能效应的必要前提。当某种酶活性对微小ｐＨ值变化敏感时,许多中间代谢产物反应,调控着动物细胞酸碱平衡。酸碱平衡是氢离子浓度的一种功能。当难于测定细胞内液和亚细胞内ｐＨ变化时,一般测定细胞外液中氢离子浓度,大多数哺乳动物细胞外液氢离子浓度维持在低水平状态(40×10-9ｍｏｌ/Ｌ或40ｎＥｑ/Ｌ,ｐＨ74)。细胞内液氢离子浓度比细胞外液高,哺乳动物肌肉细胞胞液ｐＨ值67～71变化,这种差异是维持细胞内代谢产物浓度的重要因子。但在细胞内,亚细胞器与胞液间也存在氢离子浓度差异。线粒体内…