菜籽饼发酵菌株筛选研究

本研究对利用菜籽饼的菌株筛选，发酵后产品质量变化及影响发酵的主要因素进行了分析，结果表明：ｙ＿１、ｙ＿２、ｙ＿５是发酵利用菜籽饼优良的３个非互为拮抗的菌株，且三菌株混合发酵比单一菌株发酵效果好，其混合发酵可提高蛋白质含量１２％左右，硫代葡萄糖苷降低了１５．１６～１８．９０μｍｏｌ／ｇ，降解率达６０％～８０％，发酵后产品含有１７种氨基酸，氨基酸总量为４５．５４％，优于山东滕县以豆饼为主生产的活性高蛋白饲料。且发现供氧及原料加水量是影响菜籽饼发酵的主要因素，原料加水７０％有利于菜籽饼发酵顺利进行。     

茧层量差异家蚕品种后部丝腺细胞和血液组织的蛋白质表达谱分析

为了研究家蚕茧层量性状的分子调控机制,采用蛋白质双向电泳和图像分析技术,分析了遗传背景基本相同,而结茧性状和茧层量具有明显差异的正常茧、薄皮茧、裸蛹3个家蚕品种的丝腺细胞和血液组织的蛋白质表达与茧层量的关系。结果表明:裸蛹品种的丝腺细胞蛋白斑点与正常茧品种的蛋白斑点的匹配率仅在65%左右,且存在35%左右的特异蛋白斑点,暗示裸蛹性状可能是主效基因控制的微效多基因遗传;3个品种后部丝腺细胞特异蛋白斑点、匹配蛋白斑点按等电点划分的分布规律具有明显差异,而血液组织相应的分布规律非常相似,暗示丝腺细胞中的蛋白及其基因对家蚕茧层量性状的作用要大于血液组织中的蛋白及其基因;正常茧、薄皮茧和裸蛹3个品种后部丝腺细胞中特异蛋白斑点及上调和下调蛋白斑点中,可能分别存在着与家蚕高茧层量性状、结薄皮茧性状以及不结茧性状有关的蛋白质。     

牦牛瘤胃内饲料蛋白质降解率的研究

用瘤胃尼龙袋技术测定了１１种常见饲料在牦牛瘤胃内的降解率。根据饲养水平,瘤胃食糜的外流速度估计为０．０６７／ｈ。测定结果表明,玉米、豌豆秸粉、菜籽饼、豌豆、鱼粉、曲拉、肉骨粉、青稞、甲醛鱼粉、甲醛菜籽饼和麸皮的粗蛋白（ＣＰ）降解率分别为０．６８、０．５６、０．４４、０．８５、０．４９、０．５５、０．８１、０,８３、０．３８、０,４８和０．７９,干物质（ＤＭ）降解率依次为０．６８、０．３０、０．４９、０．７３、０．５０、０,５４、０,５９、０．８２、０．３２、０．４９和０．７４。     

生长激素对蛋白质动态代谢与氨基酸利用的调控

生长激素是调节动物生长的众多激素中最重要的一种 ,它通过在肌肉与脂肪组织之间极强的营养重分配作用 ,增加体蛋白沉积 ,减少脂肪沉积 ,从而改变这两种组织的生长状况来实现其促生长功能。动物体内蛋白沉积是蛋白合成与降解同时进行的两个过程动态平衡的结果。本文综述了近年来有关生长激素对动物蛋白质动态代谢与氨基酸利用调控方面的研究结果 ,指出生长激素使蛋白质合成与降解速率均增加 ,整体蛋白质周转代谢强度加大 ,从而导致蛋白质沉积增加。     

BMY公牛对不同能量蛋白比日粮的消化代谢试验

[目的]为了研究12月龄BMY公犊牛对不同日粮中各营养成分的代谢情况。[方法]采用12月龄BMY公犊9头,分成3组,分别饲喂低能低蛋、中能中蛋和高能高蛋比日粮。[结果]日粮中DM、N、ADF和NDF的表观消化率随着日粮中能量蛋白比水平的提高而增加,其中,三个试验组间DM和N的表观消化率之间无显著性差异（P〉0.05）,但低能量蛋白比日粮组的N表观存留率、ADF和NDF的表观消化率显著低于中、高两个试验组（P〈0.05）,而中和高蛋白能量比日粮组N的表观存留率、ADF和NDF的表观消化率之间无显著性差异（P〉0.05）。     

Separation of protein and lactose intake over meals dissociates postprandial glucose and insulin concentrations and reduces postprandial insulin responses in heavy veal calves

The present study examined, at identical daily nutrient intakes, the impact of separating protein and lactose intakes across two daily meals on the metabolic and endocrine status in heavy veal calves. Calves were assigned to one of six degrees of separating protein and lactose over the two meals (termed nutrient synchrony, SYN 1-6; 6 calves/treatment). They were fed the protein-rich (P-)meal and the lactose-rich (L-)meal at 06:00 and 18:00h, respectively, or vice versa. At SYN 1, calves were fed with 50% of the daily protein and 50% of the daily lactose intake in each meal. Protein and lactose were iso-energetically exchanged between the two daily meals from SYN 1 to 6. At SYN 6, 85% of the daily protein and 20% of the daily lactose was fed in the P-meal and the remainder in the L-meal. Blood samples were collected hourly during 24h. Mean 24h glucose concentrations increased and insulin concentrations decreased from SYN 1 to 6. Postprandial 5h areas under concentration curves (AUC(0-5h)) of glucose increased with increasing meal lactose content. AUC(0-5h) of non-esterified fatty acids increased after P- and L-meals from SYN 1 to 6. Urea concentrations increased after L-meals from SYN 1 to 6, but decreased after P-meals from SYN 1 to 6. Insulin AUC(0-5h) decreased after L-meals and after P-meals from SYN 1 to 6. Nutrient asynchrony did not affect insulin-like growth factor-1, glucagon, growth hormone, leptin, 3,5,3'-triiodothyronine and thyroxine. In conclusion, separation of protein and lactose intake over meals inhibited insulin responses to a lactose-rich meal in heavy veal calves despite high plasma glucose concentrations.     

近红外反射光谱(NIRS)技术分析奶粉品质的研究

奶粉中蛋白质和脂肪是影响奶粉营养品质的主要因素,利用近红外反射光谱分析技术对来自国内不同地区的奶粉共900份样品进行蛋白质和脂肪成分测定分析。研究了不同的样品数日、光谱预处理和散射校正技术对发展奶粉近红外测定定标模型的影响。结果表明．在样品数目为200—400范围内建立的定标分析模型较理想;数学预处理中以一阶导数较好,且以“1,4,4,1”的处理组合最为理想;光谱散射校正中采用“标准正态变量转换(SNV) 趋势变换法(De—trending)”的组合建立回归方程效果较好。利用改进最小二乘法回归技术(Modified PLS)建立多种定标模型,并进行交叉验证(cross—Validation)来分析各种因素对定标模型的影响。同时筛选出较理想的蛋白质和脂肪定标分析回归方程,其中蛋白质和脂肪含量的相关系数高速0．973和0．850。探讨了NIRS技术在建模应用中的一些影响因素,以及由NIRS技术建立奶粉分析模型用于快速分析和在线检测的可行性。     

Hemostatic changes in dogs with naturally occurring sepsis

Sepsis is a frequent source of morbidity and mortality in critically ill patients. The goal of this case control study was to measure hemostatic changes in dogs with naturally occurring sepsis. Blood was collected within 24 hours of admission from 20 dogs that fulfilled the criteria for sepsis. Sepsis was defined as histologic or microbiological confirmation of infection and 2 or more of the following criteria: hypo- or hyperthermia, tachycardia, tachypnea, or leukopenia, leukocytosis, or > 3% bands. Culture and sensitivities were performed on appropriate samples from all septic dogs. Twenty-eight control dogs were enrolled on the basis of normal results of physical examination, CBC, serum biochemistry, and coagulation profile. Plasma samples were analyzed for prothrombin time (PT), partial thromboplastin time (PTT), fibrin(ogen) degradation products (FDP), D-dimer (DD) concentrations, antithrombin (AT) activity, and protein C (PC) activity. Data were compared between groups by chi-square or independent t-tests. PC (P < .001) and AT (P < .001) activities were significantly lower in dogs with sepsis compared to controls. Dogs with sepsis had significantly higher PT (P = .007), PTT (P = .005), D-dimer (P = .005), and FDP (P = .001) compared to controls. Platelet counts were not significantly different between groups. Ten of the 20 septic dogs (50%) died, but no association was identified between any of the measured variables and outcome. These findings are consistent with previous studies in animals with experimentally induced disease and in clinical studies of humans. On the basis of these results, further investigation of the role of AT and PC in canine sepsis is warranted.     

日粮能量和蛋白质水平对奶牛繁殖性能影响的研究进展

奶牛繁殖性能下降与能量和蛋白质有关,本文系统地介绍了日粮能量和蛋白质水平对奶牛繁殖性能影响的研究进展,并着重论述了能量负平衡(NEB)及日粮蛋白质、脂肪酸和氨基酸对奶牛繁殖的影响.     

Effects of stress on endocrine and metabolic processes and redirection: cross talk between subcellular compartments

Recent advances in genome analysis and biochemical pathway mapping have advanced our understanding of how biological systems have evolved over time. Protein and DNA marker comparisons suggest that several of these systems are both ancient in origin but highly conserved into today's evolved species. However, remnants of some of the more ancient functions of these chemical systems can run in conflict with the functions that those same pathways serve in complex organisms and tissue systems today. Relevant to the present topic, nitric oxide (NO) and superoxide anion (O₂^•−), ancient cellular molecules in evolutionary terms, are recognized today as both necessary for the well-being and stable health of cells but also injurious to cells as elaborated in conjunction with the cellular stress response. Why the dichotomy? This question underlies one of the basic issues challenging researchers as well as practitioners in their approach to disease management. The fundamental proinflammatory response of the innate immune system of the host is needed for pathogen control but can be injurious to tissues from “collateral damage” from NO- and O₂^•−-derived reactive molecules capable of affecting protein function via post-translational chemical modification. This review highlights newer aspects of the biochemistry of the NO- and O₂^•−-mediated innate proinflammatory response and further show how protein and tissue damage via overproduction of reactive nitrogen and oxygen intermediary molecules such as peroxynitrite (ONOO⁻) might be targeted to specific epitopes of proteins. Changes in the regulation of metabolism in response to proinflammatory disease states are discussed for GH signal transduction and tissue specificity.