小肽对鲤鱼免疫力的影响

选用1 80尾体质量相近、健康的成鲤作饲养试验,随机分成4组,设对照组1个,试验组3个(日粮中分别添加0 .3 %、0 .6 %、1 .0 %的小肽)。试验结束后,观察在基础日粮中添加不同量的小肽对成鲤血液生理生化指标及脏体器官的影响,以探讨小肽对鲤鱼免疫力的影响。结果表明,1 )试验组成鲤血清中的免疫球蛋白(IgM)和补体(C4)的浓度均高于对照组(P <0 .0 5) ,其中1 .0 %小肽组的IgM和C4分别为450 .81mg/L和1 7.69mg/L ,比对照组提高1 4 .6 %和95 .7%,补体(C3 )差异不显著(P >0 .0 5) ;尿素氮(BUN)含量比对照组低(P <0 .0 5) ,尤其是1 .0 %小肽组比对照组降低2 7.9%;2 )试验组成鲤的内脏比、肝体比和脾体比均比对照组提高,但差异不显著(P >0 .0 5) ,随着饵料中小肽用量的增加肾体比也逐渐提高,1 .0 %小肽组的肾体比比对照组提高56.3 %(P <0 .0 5)。     

HPLC测定饲料源小肽产品中赖氨酸含量

将蛋白饲料源小肽产品按照GB/T 18246-2000中酸水解法进行水解及相应的处理,获得氨基酸混合液与2,4-二硝基氯苯(CDNB)衍生化反应后,其中赖氨酸生成二硝基氯苯赖氨酸(DNP-LYS),经日本岛津SPD-10AVG高效液相色谱(HPLC),C18柱分离,UV350 nm检测,衍生后氨基酸混合物得到较好的分离,赖氨酸最低检出量2μg.     

雏鸡肠道底物肽与血液循环中肽关系的研究

为了研究鸡肠道完整吸收肽与肠道中底物肽间的关系,在鸡清醒状态下,用胰酶,肠肽酶水解制备的酶解血蛋白（ＢＨ）进行了十二指肠灌注试验,对照组灌注生理盐水,心脏采血制备的血浆ＨＰＬＣ分析结果表明,雏鸡每在１００ｇ体重灌注１ｍｌ６．２５％ＢＨ２０ｍｉｎ后,循环中的某些肽量和总肽量显著（Ｐ〈０．０５）,或极显著（Ｐ〈０．０１）,地高于对照,ＢＨ组肽量比对照组提高３１．４％,血浆中肽量的增加与底物中提供的肽种     

小肽与游离氨基酸对雏鸡血液循环中肽的影响

为了研究鸡肠道是否具有完整吸收和合成肽的能力，用主要由小肽组成的酶解酪蛋白（ＣＳＰ）和相应组成的氨基酸（ＦＡＡ）混合物，进行了灌注和＾３Ｈ－Ｔｙｒ同位素标记试验。ＨＰＬＣ分析结果表明灌注后１０ｍｉｎＣＳＰ组门静脉血液循环中的一些肽量和总肽量显著地（Ｐ〈０．０５）高于灌注前对照，ＣＳＰ＋ＦＡＡ组和ＦＡＡ组；与对照相比，ＣＳＰ组肽量提高６６．２６％。ＦＡＡ组注后５ｍｉｎ，门静脉血浆中一些肽量显著地高于     

小肽营养的研究进展

近些年来的试验研究证明,在氨基酸的消化、吸收和代谢中,小肽起着非常重要的作用。国内外时小肽已进行了不少研究,本文对小肽释放、吸收机制、营养作用进行综述。     

酪啡肽研究新进展

酪蛋白是乳中最重要的成分。酪蛋白是乳源活性肽的重要来源,乳源生物活性肽是酪蛋白在消化酶作用下释放的,能被机体直接吸收,具有多种生物学功能。其中酪啡肽是最重要的乳源生物活性肽之一。作者就酪啡肽的检测、吸收及其生理功能进行综述,并介绍了近几年国内外酪啡肽研究的进展。     

小肽的动物营养研究进展

主要阐述了小肽的转动、吸收和营养作用,并对其在畜牧业中的应用及前景作了简要的概述。     

小肽营养与生理调控机制

小肽营养是蛋白质营养理论的发展与重要补充,研究小肽营养作用与吸收代谢特点,对全面理解小肽营养具有重要意义,文章将对该方面研究进展做一概括性总结。     

小肽的吸收机制与营养价值研究进展

小肽是蛋白质的主要消化产物,在氨基酸的消化、吸收和代谢中起着非常重要的作用。文章就小肽在单胃动物和反刍动物的吸收机制、小肽的营养作用和影响小肽吸收的因素以及小肽在蛋白质代谢中的作用分别加以综述。     

Mechanism of blood coagulation in common carp (Cyprinus carpio)

In vitro, carp blood was anticoagulated by using MgSO₄ at a final concentration of 22.2 mmol L^?1 and sodium citrate at a final concentration of 11.8 mmol L^?1. The coagulation times for carp plasma diluted by ion‐free water (1:1), and that of carp plasma to which thrombocytes and small lymphocytes were added, were measured at 23 °C using standard methods, and then contrasted with the coagulation times for plasma obtained from chickens and rabbits. The shapes of the thrombocytes and small lymphocytes, which were either wet mounted or stained with hematoxylin and eosin, were observed under a light microscope. We found that: (i) the coagulation reaction of carp blood was significantly (P < 0.01) accelerated by the addition of ion‐free water; (ii) the three types of blood cells (thrombocytes, small lymphocytes and red blood cells) promoted plasma coagulation to a similar extent (P > 0.05); (iii) in carp Mg²⁺ plasma and K₂C₂O₄ plasma, the thrombocytes were usually morphologically normal, but many small lymphocytes were destroyed and became aggregated; (iv) in the citrate plasma, thrombocytes were often aggregated, but the small lymphocytes were usually morphologically normal; and (v) the coagulation time for chicken and rabbit plasma was significantly extended by adding ion‐free water.     

小肽添加剂对生长猪生长性能的影响

试验研究三种不同的小肽添加剂制品对生长猪生长性能的影响。试验选用72头初始体重在(34.64±8.32)kg的杜×长×大三元阉公猪,随机分为4个处理,每个处理6个重复,每个重复3头猪试验各组分别饲喂基础日粮(对照组),基础日粮加100mg/kg小肽A(小肽A组),基础日粮加100mg/kg小肽B(小肽B组),基础日粮加50mg/kg小肽C(小肽C组),试验期28d。测定其对生长猪的生长性能的影响,结果表明,与对照组相比,小肽A组、小肽B组和小肽C组的生长猪的平均采食量分别提高了9.8%、7.0%和12.5%(P0.05),平均日增重分别提高了15.8%、12.8%和21.7%(P0.05),料肉比分别降低了5.1%、6.3%和8.5%(P0.05)。     

草鱼组织中阿维菌素和伊维菌素的多残留检测

建立了草鱼肌肉（包括皮）中阿维菌素和伊维菌素的多残留检测方法。样品用乙腈提取,正己烷脱脂净化,多拉菌素作内标,经1-甲基咪唑和三氟乙酸酐的乙腈溶液在室温下避光衍生化并在甲醇中水解后,进行HPLC-FLD检测分析。结果表明,阿维菌素和伊维菌素在5~100 ng/g范围内具有良好线性,检测限分别为1.0 ng/g和1.2 ng/g,定量限分别为3.4 ng/g和4.0 ng/g,日间提取回收率分别为96.42%~103.10%和94.23%~101.76%,日内和日间变异系数分别小于4.37%、6.82%和6.73%、8.84%。该方法高效、灵敏、简便,其灵敏度、回收率和重现性等符合有关兽药残留检测要求,可用于草鱼肌肉中阿维菌素和伊维菌素的多残留检测。     

Utilization of dipeptide/protein based diets in larval and juvenile Koi carp – post‐prandial free amino acid levels

We have shown previously that diets in which the nitrogen portion is based on synthetic dipeptides (PP) resulted in weight gain by rainbow trout alevins when free amino acid (FAA) based diets did not. However, the protein‐based diet used as a control in the previous study resulted in a significantly better performance of fish than peptide‐ or FAA based diet fed fish. Therefore, the objectives of our study were (i) to test how stomachless fish respond to peptide‐based diets, (ii) to evaluate PP and protein‐PP mixture diets and (iii) to examine if post‐prandial response to FAA concentrations in the fish body can be used as an indicator of the availability of dietary amino acid sources. The first experiment was conducted with a 4‐day old Koi carp (Cyprinus carpio) larvae and included groups fed a casein–gelatin (CG) based diet, a commercial diet and live Artemia nauplii. In the second experiment, fish fed live Artemia for 3 weeks (69 ± 12 mg) were placed in glass aquaria in triplicate per dietary treatment. Four diets provided equivalent amounts of nitrogen in the form of a CG, a PP, a 50% PP and 50% CG (PP50) mix and as FAA. Fish were fed at 1 and 3 h intervals, and the survival and growth were monitored during the second and third weeks of experiments 1 and 2 respectively. Following the completion of feeding, juvenile carp were sampled prior to feeding and 3 h after a meal. Whole body FAA analyses were carried out. We observed marginal suitability of the CG diet for larval Koi carp, as earlier indicated in common carp. Juvenile Koi carp fed the CG diet achieved 236 ± 19 mg, whereas PP50, PP and FAA diet fed fish grew to 140 ± 37, 70 ± 8 and 73 ± 5 mg respectively. Free amino acids in the fish body, and in particular indispensable amino acids (IDAA), were excellent indicators of dietary availability. The present experiment shows that a dietary 1:1 ratio of protein to synthetic PPs results in better growth, survival and whole body IDAA concentrations in relation to FAA‐ and PP‐based diets confirming earlier reports on the use of synthetic PP‐based diets, although this diet does not match the performance of complete protein, CG‐based diet.     

小肽的吸收与转运及其营养作用

随着动物营养学研究的发展,蛋白质营养的研究也在逐步深入,由原来的粗蛋白营养发展到氨基酸营养,进一步发展到现在的小肽营养。本文就小肽的吸收、转运、营养及其在动物生产中的应用,以及目前小肽研究领域中存在的问题等方面进行阐述。     

Effect of gossypol on blood serum parameters and small intestinal morphology of male broilers

Summary In the present study, the effect of varied gossypol (GOSS) amounts was investigated on blood parameters, the digesta pH, villus height, villus width, and crypta depth, width of duodenum, jejunum and ileum. A total of one hundred eight Ross 308 male broilers were fed with four diet groups as follows: no gossypol (control), gossypol rate 62 mg/kg (GOSS 62), gossypol rate 124 mg/kg (GOSS 124) and gossypol rate 186 mg/kg (GOSS 186). The effect of used gossypol amounts on blood parameters was not found to be statistically significant. Increases in digesta pH values of jejunum and ileum with GOSS 186 diet group were found to be statistically significant. The results also indicated that, except duodenum villus height, there was no statistical difference effect of GOSS on epithelial cell thickness, villus height, villus width, crypta depth and crypta width of the duodenum, jejunum and ileum. There have been no clearly negative effects of higher gossypol amounts up to 186 mg/kg diets on these parameters.     

地塞米松对肉仔鸡小肠小肽吸收的影响

本试验旨在利用地塞米松构建应激模型,研究应激对肉仔鸡肠道小肽吸收的影响。选取200只21日龄、体质量相近的雄性Arbor Acres(AA)肉仔鸡,随机分为4个处理,每只腹部皮下连续7 d注射1 mL地塞米松磷酸钠注射液(不同处理注射剂量分别为0、0.1、0.52、.5 mg.kg-1BW)。最后一次注射8 h后(15:00)空腹称取体质量,采血、取空肠,进行组织学、皮质酮、小肽Gly-Sar吸收和小肽转运载体PepT-1 mRNA表达的检测,结果表明:⑴地塞米松显著降低肉仔鸡体增质量(P0.05);⑵地塞米松显著抑制肉仔鸡空肠外翻肠囊及刷状缘囊膜对小肽Gly-Sar的吸收(P0.05);⑶地塞米松显著增加肉仔鸡空肠隐窝深度(P0.05),显著降低绒毛高度、吸收面积和绒毛高度/隐窝深度比值(P0.05),对绒毛宽度影响不显著(P0.05);⑷地塞米松显著降低肉仔鸡空肠小肽载体PepT-1 mRNA的表达量(P0.05)。由本试验推测应激可抑制肉仔鸡小肽吸收,产生原因与空肠黏膜形态受损及小肽转运载体PepT-1 mRNA表达量受到抑制有关。     

小肽的生产方法和研究方向

小肽营养已成为蛋白质营养研究的热点之一,本文就小肽的生产方法和今后研究方向作一综述。     

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。     

Pharmacokinetics of cefquinome in crucian carp (Carassius auratus gibelio) after oral,intramuscular, intraperitoneal,and bath administration

The pharmacokinetics (PK) of cefquinome (CEQ) was studied in crucian carp (Carassius auratus gibelio) after single oral, intramuscular (i.m.), and intraperitoneal (i.p.) administration at a dose of 10 mg/kg body weight and following incubation in a 5 mg/L bath for 5 hr at 25°C. The plasma concentration of CEQ was determined using high‐performance liquid chromatography (HPLC). PK parameters were calculated based on mean CEQ concentration using WinNonlin 6.1 software. The disposition of CEQ following oral, i.m., or i.p. administration was best described by a two‐compartment open model with first‐order absorption. After oral, i.m., and i.p. administration, the maximum plasma concentration (C_max) values were 1.52, 40.53, and 67.87 μg/ml obtained at 0.25, 0.23, and 0.35 hr, respectively, while the elimination half‐life (T_1/2β) values were 4.68, 7.39, and 6.88 hr, respectively; the area under the concentration–time curve (AUC) values were 8.61, 339.11, and 495.06 μg hr/ml, respectively. No CEQ was detected in the plasma after bath incubation. Therapeutic blood concentrations of CEQ can be achieved in the crucian carp following i.m. and i.p. administration at a dosage of 10 mg/kg once every 2 days.