谷氨酰胺在动物生产中应用的研究进展

谷氨酰胺是一种重要的非必需氨基酸,对动物肠道健康的改善作用尤为显著。本文就谷氨酰胺在断奶仔猪、家禽、水产动物、反刍动物生产中应用的研究进展作一综述。     

饲料中添加谷氨酰胺对断奶仔猪的作用

谷氨酰胺是小肠上皮细胞分化、增殖的重要能源物质,也是蛋白质、嘌呤等体内重要物质合成的必需物质。它能够修复受损肠道,提高机体免疫功能,是一种在动物血液和乳汁中含量丰富的条件性必需氨基酸。谷氨酰胺具有参与动物体内营养物质代谢,促进肠道细胞的增殖,提高机体免疫力,降低腹泻概率等作用。文章从断奶仔猪肠道,生长性能,免疫和抗氧化功能等几个方面,综述了谷氨酰胺对断奶仔猪的作用,为实现高效,安全的仔猪生产奠定基础。     

丙氨酰谷氨酰胺二肽在动物生产中的应用

谷氨酰胺是一种条件性必需氨基酸,对动物健康与生长具有重要意义。丙氨酰谷氨酰胺二肽作为谷氨酰胺替代品,具有与谷氨酰胺基本相同的生物功能,近年来颇受业界关注。本文综述了丙氨酰谷氨酰胺二肽在动物生产中的作用。     

谷氨酰胺在动物生产中的应用研究

谷氨酰胺(Gln)在促进动物的生长性能、维持肠道健康、改善免疫系统和抗氧化上具有十分重要的作用。本文对谷氨酰胺的结构,对动物肠道结构、免疫系统的调节作用,抗氧化作用及其在动物生产上的应用进行了综述。     

α-酮戊二酸对动物肠道黏膜作用的研究进展

谷氨酰胺是条件性必需氨基酸,也是三羧酸循环的中心物质,它在三羧酸循环中可以转化为谷氨酸,并能进一步形成谷氨酰胺。作为谷氨酰胺的前体物质,α-酮戊二酸是胃肠道细胞的主要能量来源,可以促进胃肠道细胞增殖,对维持胃肠道健康有很重要的作用,因此它能成为谷氨酰胺的最佳替代物。α-酮戊二酸将用于人类临床营养,同样可以应用于动物生产上,文章仅就α-酮戊二酸对动物机体肠道黏膜的作用进行了综述。     

浅谈谷氨酰胺对断奶仔猪的作用

<正>谷氨酰胺是哺乳动物血液和母猪乳汁中一种含量非常丰富的游离氨基酸,是蛋白质、嘌呤等体内重要物质合成的必需物质;谷氨酰胺同时也是淋巴细胞、小肠上皮细胞分化、增殖的重要能源物质。所以,谷氨酰胺在受损肠道的修复及免疫功能中发挥着重要的作用。随着近年的研究发现,动物在病例状态或应激条件下,谷氨酰胺的合成不能满足时,容易发生体内谷氨酰胺的枯竭,需要从外界补充,这时谷氨酰胺就成为了必需氨基酸,因而,谷氨酰胺也被称为条件性必需氨基酸。     

谷氨酰胺二肽在断奶仔猪中应用的研究进展

谷氨酰胺(glutamine,Gln)是动物血液中最丰富的游离氨基酸之一,对仔猪的健康与生长具有重要意义,但由于Gln具有热不稳定性及溶解度低等缺点,影响了Gln在动物生产中的应用。谷氨酰胺二肽是Gln和其他氨基酸形成的二肽,能克服Gln在应用中的缺陷,近年来受到国内外动物营养学家的广泛关注。本文较系统地阐述了谷氨酰胺二肽的代谢、生理作用、对仔猪生长性能的调节及其在仔猪生产中的应用前景,为合理配制早期断奶仔猪日粮,提高饲料转化率,降低仔猪断奶后腹泻率和死亡率,增强机体免疫能力提供理论依据。     

谷氨酰胺对幼犬生长发育的影响

谷氨酰胺是动物血液中最丰富的一种游离氨基酸,在许多动物细胞中其浓度也相对较高。除作为蛋白质和肽的成分外,谷氨酰胺在维持机体酸碱平衡,调节机体免疫机能以及为特定器官、组织甚至细胞的物质和能量代谢提供原料等方面具有重要作用,特别在维持健康状态或修复病理状态下,机体肠道结构和功能的完整性的活动中具有其它氨基酸不可替代的作用。越来越多的研究结果表明：当动物处于应激或病理状态时,内源合成的谷氨酰胺不能满足需要,甚至会发生体内谷氨酰胺的耗竭,此时必须由外源补充。本试验就谷氨酰胺对断奶仔犬的生长发育的影响进行观察。     

谷氨酰胺的作用机理及开发进展

谷氨酰胺(GlutamineGln)是L-谷氨酸的γ-羧基酰胺化物,是体液中最丰富的氨基酸之一,在生命活动中起着重要的作用,如可增强免疫功能、维持酸碱平衡、增加细胞体积、增强肌肉细胞内蛋白质的合成等。近年来的医学和动物营养学的发现表明,Gln的缺乏会引发多种疾病或导致动物生长发育的滞缓,现已普遍认为Gln是一种条件性必需氨基酸。所以,Gln是一种极有发展前景的新型药物和动物营养性饲料添加剂。1谷氨酰胺在动物营养中的作用机理动物胃肠道正常的免疫功能包括两个方面:一是非特异性的,如胃酸、粘液、消化酶、正常菌群以及巨噬细胞、肥大细胞…     

Gln与Ala-Gln对缓解LPS诱导动物免疫应激的研究进展

谷氨酰胺（glutamine,Gln）又称α-氨基戊酰胺酸、谷氨酸-5-酰胺,是一种非必需氨基酸,在机体中发挥重要作用,被认为是一种功能性氨基酸,通常以丙氨酰-谷氨酰胺（alanyl-glutamine,Ala-Gln）形式作为饲料的添加剂。Gln与Ala-Gln不仅能促进畜禽和水产动物生长,提高机体抗氧化、免疫能力,维持肠道健康,对缓解机体免疫应激也发挥着重要作用。文章通过探讨在饲料中添加Gln与Ala-Gln对动物的影响,阐述其缓解免疫应激的作用机理,为Gln、Ala-Gln作为饲料添加剂应用提供理论依据,同时为进一步研究缓解免疫应激的作用机制提供参考。     

Oral administration of different formulations of ascorbic acid to the horse

The absorption of crystalline ascorbic acid, ascorbyl palmitate, ascorbyl stearate and a formulation of ascorbic acid was investigated in six mature Thoroughbred horses following oral administration. It was found that ascorbyl palmitate gave both highest plasma concentrations and greatest area under the curve (AUC) for ascorbic acid. Least variation between animals also occured for this preparation. No apparent absorption was seen in some animals given ascorbic acid or ascorbyl stearate.     

The role of carbonic acid in the regulation of nitrogen metabolism in the animal body. 1. Effect of changes in CO2 concentration in tissues on the processes of NH+ metabolism in rabbits

In two groups of rabbits of 24 animals each the dependence of NH4+-utilisation on the level of carbonic acid in the organism was investigates. The rabbits of the second group received injections into the abdominal cavity of 8 ml/kg body weight of a 5% NaHCO3-solution (enriched with CO2, pH 7.35) for the purpose of increasing the concentration of carbonic acid in the blood (pCO2: HCO3) and for the purpose of decreasing it an amount of NaCl-solution, which, in its content of Na+, was equivalent to the NaHCO3-dose. The difference in the concentration of carbonic acid in the blood between the two groups under the conditions of the experiment was between 30 and 35%, the pH-value was approximately the same. In order to investigate the NH4+-metabolism the animals of both groups received injections of 2 ml/kg body weight of a 1% (NH4)2HPO4-solution, their protein metabolism was studied after the intravenous injection of 2-14C-glycine. Together with the increase or decrease resp. of the level of carbonic acid in the organism, the keto acid concentration increases or decreases simultaneously. Due to the NH4-load the keto acid concentration in all animals decreases. it remains, however, higher in the animals with a higher HCO-3-level than in the control animals. The alpha-ketoglutarate concentration in the liver tissue of the animals with a higher HCO-3-level is, despite the NH4+-load, 87%, p less than 0.05, higher than in the control animals. The intensity of a removal of an NH4+-excess from the animal organism is directly dependent on the concentration of carbonic acid in the tissues. One hour after the NH4+-load the NH4+-concentration in the blood of the rabbits with a higher level of carbonic acid is normal again, whereas it is still 36% (p less than 0.05) higher than the original value in the control animals. In the liver and kidney tissues of the animals with an increased HCO-3-concentration 30 minutes after the (NH4)2HPO4-injection is by 16 and 14.5% (p greater than 0,05) resp. lower than that of the control animals. This is caused by the increased supply with NH4+-fixing substrates which are either formed directly or through intermediate stages by CO2-fixing reactions: oxaloacetate (the pyruvate concentration in the liver and kidney tissues compared to the control group was by 58%, p less than 0.05 lower), alpha-ketoglutarate, aspartate.(ABSTRACT TRUNCATED AT 400 WORDS)     

提高动物繁殖力的核酸疫苗研究进展

核酸疫苗也叫基因疫苗或DNA疫苗,是20世纪90年代初开发的一种新疫苗,具有稳定、安全、制备简单等优点.近年来,大量研究表明,利用核酸疫苗免疫可以有效提高动物的繁殖力,其中有些疫苗已经进入临床应用实验阶段.本文对提高动物繁殖性能的核酸疫苗的种类、作用原理及其在实验动物、家畜等多种动物上的应用研究进行了综述,以期为进一步...     

Portovenogram findings in cases of elevated bile acid concentrations following correction of portosystemic shunts.

The case records of 36 cats and dogs undergoing surgical correction of a single extrahepatic portosystemic shunt were reviewed. In 12 animals, the shunt was fully ligated during the first surgical procedure, while, in the remaining 24, the shunting vessel could only be partially ligated. Assessment of serum bile acid concentrations demonstrated complete shunt occlusion in 15 of these latter 24 animals (63 per cent) between one and six months postoperatively. Ten animals (28 per cent) had persistently high serum bile acid concentrations postoperatively. Portovenogram findings in these individuals revealed six that demonstrated shunting solely through the original vessel; In five of these, full shunt attenuation was achieved at second surgery. Further shunt manipulation was not possible in the sixth case due to extensive adhesion formation. In the remaining four animals with raised bile acid concentrations, the portovenogram demonstrated shunting through the original vessel as well as the development of multiple acquired shunts.     

Plasma bile acid elevation following CCI4 induced liver damage in dogs, sheep, calves and ponies.

Plasma bile acid concentration was determined in normal dogs,sheep, calves and ponies for three days before and six days after liver damage, induced by carbon tetrachloride. In all species, a significant increase in plasma bile acid concentration was associated with a concomitant significant increase in plasma sorbitol dehydrogenase and transferase activity. Plasma bilirubin also significantly increased in all animals except the dogs. Results suggested that plasma bile acid levels could be used to test liver function in domestic animals.     

Nutritive physiological effects of dietary fats in rations of growing swine. 6. Effect of soya oil and lard on growth performance and carcass characteristics and various blood parameters in fattening swine

Groups of each 10 boars, weight range 20-60 kg, were fed ad libitum the following 4 rations of similar protein: energy ratio: Ration I (control), Ration II (+ 2% soyaoil ), Ration III (+ 2% soyaoil + 5% lard), Ration IV (+ 7% lard). When the animals reached 60 kg body weight each group was halved. One half had free access to the above rations, while the other half were fed ad libitum on the control ration. At body weights of 50 and 100 kg the concentrations of urea, insulin, glucose and cholesterol were measured, in addition the fatty acid composition of the backfat. At the end of the experiment (100 kg) the content of fat in the carcass was calculated by determining the specific gravidity of the carcass. There was little difference in the intake of metabolizable energy (ME) of the different groups of animals at both body weight ranges as a result of the reduction in feed intake of the fat supplemented diets on account of the higher ME-content. There were little differences in the glucose and urea concentrations in the blood of the animals fed the different rations. The highest cholesterol and the lowest insulin levels were measured in groups III and IV, when 5 and 7% lard was added, respectively. The animals, continuously fed Rations III and IV over the whole period of experiment, had a significantly higher fat content (p less than 0,05) than the control animals. There was a very marked influence of the fatty acid intake on the fatty acid pattern of the backfat. Following the change of feed to the control ration at 60 kg body weight, the linoleic acid content of the animals in Groups III and IV was significantly reduced (p less than 0,001) from 15.7 to 11.2%. However this was higher than the 7.3% linoleic acid measured on the animals continuously fed the control ration.     

胍基乙酸对畜禽生产性能与肉品质的调控作用研究进展

胍基乙酸是动物体内肌酸的前体物,在机体内参与能量代谢调控。胍基乙酸作为一种新型营养性饲料添加剂,具有提高猪、鸡等动物生长性能、屠宰及繁殖性能、改善肉品质等作用。本文综述了近年来胍基乙酸在单胃动物和反刍动物上的的作用效果,主要表现在促生长的作用,提高瘦肉率与嫩度,并能减少脂肪合成,对改善肉鸡精液品质具有促进作用,为胍基乙酸在畜牧业上进一步研究做理论支撑和实践参考。     

乳酸菌对猪免疫功能调节作用及其机制研究进展

乳酸菌是人和动物胃肠道的一种优势菌群，也是动物生产中的一种重要益生菌来源，具有较强的耐酸性、耐胆盐性及黏附能力。乳酸菌在提高动物生产性能、改善肠道健康、增强免疫力等方面具有重要功能。研究证实，乳酸菌可通过影响细胞免疫、体液免疫和肠道黏膜免疫等免疫应答过程调节猪机体的免疫功能。本文综述了乳酸菌对猪机体免疫功能的影响，以期为乳酸菌在养猪业的开发应用提供参考。     

DNA sequence analysis of glycoprotein G gene of bovine ephemeral fever virus and development of a double oil emulsion vaccine against bovine ephemeral fever

The surface glycoprotein G is considered as the major neutralizing and protective antigen of bovine ephemeral fever virus (BEFV). Comparison of the deduced amino acid sequence of G protein of BEFV isolates during the period 1984-2004 outbreaks in Taiwan showed amino acid substitutions in the neutralizing epitopes. All the isolates differ markedly in the neutralizing epitope at the same amino acid positions compared to the currently available killed vaccine strain (Tn73). Tn88128 strain isolated in 1999 showed the maximum variability of 12 amino acids, 5 amino acid in the neutralization epitope and 7 apart from, respectively. Combinations of both Tn88128 (1999) and commercially available vaccine strain (Tn73) were developed and its safety was evaluated in mice, guinea pigs, calves, and pregnant cows. None of the animals showed any adverse effect or clinical signs. Calves were immunized with commercial vaccine (Tn73) and, combined vaccine (Tn73 and Tn88128), respectively, with adjuvants such as Al-gel and water-in-oil-in-water (w/o/w) oil and PBS alone and challenged with Tn88128 strains. Except PBS administered animals, all the vaccinated animals showed protective immune response. However, animals immunized with combined vaccine plus w/o/w adjuvant elicited stronger neutralization antibodies and long lasting immunity compared to other vaccines.     

Metabolism-oriented determination of amino-acid requirement by means of catabolic rates of 14C- and 15N-labelled lysine under maintenance

Male Wistar rats (of 60 g live weight) allotted in 10 groups were fed diets with gradually increasing lysine levels ranging from 1.4 to 7.4 g lysine/16 g N. Feed intake was restricted so much that the experimental animals did not change their live weights during the last 3 days of the 8-day experiment period. On the 7th experimental day, 4 animals of each group were injected i.p. 14-C-L-lysine, the 14CO2-excretion being subsequently measured over a period of 2 hours. On the next day, 6 animals of each group were applied an i.p. injected of 15N-L-lysine, the urine being collected over the following 24-hour period to measure the 15N-frequency. Applying both labelling methods, an increased catabolisation of the amino acid was observed after the metabolically necessary lysine requirement had been covered. The methods are very sensitive and revealed, under the experimental conditions chosed, a lysine requirement coverage of about 3 g lysine/16 g N. The possibility of using also 15N-labelled compounds in the metabolism-oriented amino acid requirement determination is likely to facilitate the transfer of the methodology to farm animals and would thus allow to study the amino acid requirement of man. The metabolism-oriented amino acid requirement determination will likewise allow to estimate exact amino acid requirement data under conditions that cannot be rated on the basis of productive yields.