The interaction among age,thermal acclimation and growth rate in determining muscle metabolic capacities and tissue masses in the threespine stickleback,Gasterosteus aculeatus

Thermal acclimation may directly modify muscle metabolic capacities, or may modify them indirectly via effects upon physiological processes such as growth, reproduction or senescence. To evaluate these interacting effects, we examined the influence of thermal acclimation and acclimatization upon muscle metabolic capacities and tissue masses in 1 + stickleback, Gasterosteus aculeatus, in which confounding interactions between temperature and senescense should be absent. Furthermore, we examined the influence of thermal acclimation upon individual growth rate, muscle enzyme levels and tissue masses in 2 + stickleback sampled at the beginning of their final reproductive season. For 1 + stickleback, cold acclimation more than doubles mitochondrial enzyme levels in the axial muscle. Thermal acclimation did not change the condition of 1 + stickleback at feeding levels which could not maintain the condition of 2+ stickleback. Compensatory metabolic responses to temperature were not apparent in field acclimatized 1 + stickleback. The growth rate of 2 + stickleback was markedly affected by temperature: warm-acclimated fish generally lost mass even at very high levels of feeding (up to 78 enchytraid worms per day) while cold-acclimated fish gained mass. This suggests that warm temperatures accelerate the senescence of 2 + stickleback. Generally, muscle enzyme activities increased with growth rate. In axial muscle, the relationships between CS activity and growth rate differed with acclimation temperature. Independent of the influence of growth rate, CS activities were consistently higher in cold- than warm-acclimated 2 + stickleback, suggesting compensatory increases of CS activity with cold acclimation. Corresponding author; This paper is dedicated to the memory of Gerry J. FitzGerald who passed away on March 14, 1994.     

复合微量元素营养舔砖对藏羊血清抗氧化能力和免疫功能的影响

试验旨在研究复合微量元素营养舔砖对藏羊血清抗氧化能力和免疫功能的影响。分别于两牧户家选择体况良好、年龄体重相近、饲养管理相同的放牧藏羊30只,一组为对照组（放牧）,另一组为试验组（放牧加补饲复合微量元素营养舔砖）,每组3个重复,每个重复10只。试验组补饲复合微量元素营养舔砖,试验期6个月。结果表明：复合微量元素营养舔砖可以显著提高放牧藏羊血清总抗氧化能力和总超氧化物歧化酶活性（P〈0.05）,极显著提高血清IgM（P〈0.01）及显著提高IgA含量（P〈0.05）。说明复合微量元素营养舔砖可以在一定程度上提高放牧藏羊的抗氧化能力,增强其免疫功能。     

肌肽与维生素E对育肥猪肉品质和抗氧化性能的影响

本试验旨在研究肌肽与维生素E单独及联合使用对育肥猪肉品质和抗氧化性能的影响。试验采用2因素2×3析因设计,设3个肌肽水平(0、50、100 mg/kg),2个维生素E水平(0、200 mg/kg),选择90头体重约为70 kg的“杜×长×大”三元杂交育肥猪,按体重相近、性别比例相同原则,随机分为6组,每组3个重复,每个重复5头猪。预试期为7 d,试验期为42 d。结果表明:1)饲粮中添加肌肽能显著提高屠宰后45 min肌肉的p H和降低贮存48 h肌肉的滴水损失(P<0.05),极显著提高屠宰24 h后肌肉的p H和降低贮存24 h肌肉的滴水损失(P<0.01);维生素E能极显著降低贮存24和48 h肌肉的滴水损失(P<0.01),二者均能显著改善肉色(P<0.05)。肌肽与维生素E在改善肉色和降低贮存24 h肌肉的滴水损失上存在互作效应(P<0.05),且联合添加优于单独添加。2)饲粮中添加肌肽可显著提高育肥猪血清总抗氧化能力(T-AOC)及总超氧化物歧化酶(T-SOD)和过氧化氢酶(CAT)活性(P<0.05),极显著提高谷胱甘肽过氧化物酶(GSH-Px)活性(P<0.01),维生素E可极显著提高育肥猪血清T-AOC及T-SOD和GSH-Px活性(P<0.01)。在提高血清的T-AOC和GSH-Px活性上,二者存在显著互作效应(P<0.05),且联合添加优于单独添加。3)肌肽可显著降低贮存24 h背最长肌的丙二醛(MDA)含量(P<0.05),极显著降低贮存48、72和96 h背最长肌的MDA含量(P<0.01);维生素E可极显著降低贮存24、48、72和96 h背最长肌的MDA含量(P<0.01),且肌肽与维生素E对贮存48 h背最长肌的MDA含量存在显著互作效应(P<0.05)。综上,饲粮中添加100 mg/kg的肌肽、200 mg/kg的维生素E为最优组合。     

姜黄素的理化特性、抗氧化功能及其在肉鸡生产中的应用

姜黄素是从姜科植物姜黄中提取的一种多酚类活性物质,具有多种生物学功能.近几年,姜黄素作为天然抗氧化剂对机体抗氧化功能的影响引起了人们的广泛关注,其作为一种绿色、新型的饲料添加剂应用于肉鸡生产也成为了国内外的研究热点之一.本文主要介绍了姜黄素的理化性质、生物利用率、抗氧化功能及其在肉鸡生产中的应用现状.     

鹿血清蛋白抗氧化肽体外抗氧化性及其机理研究

在碱性蛋白酶最适条件下水解鹿血清蛋白,水解时间为0~5 h,鹿血清蛋白抗氧化肽的水解度(DH)随着水解时间增加而增加(P0.05),鹿血清蛋白抗氧化肽还原能力、清除自由基的作用和Cu2+螯合能力随着水解时间的增加而显著提高(P0.05),鹿血清蛋白抗氧化肽能有效抑制硫代巴比妥酸反应物质(TBARS)生成(P0.05)。结果表明,鹿血清蛋白抗氧化肽的抗氧化活性取决水解时间,鹿血清蛋白抗氧化肽是有效的抗氧化剂。     

苯并（a）芘对双齿围沙蚕抗氧化酶活性和细胞色素P450基因表达的影响

在实验室条件下,利用诱导试验分析了不同浓度苯并（ a）芘[ B（ a） P]对双齿围沙蚕Perinereis aibuhit-ensis （体质量为1.5 g±0.5 g）细胞色素P450基因表达和肌肉组织抗氧化酶活性的影响。结果表明：双齿围沙蚕细胞色素P450基因表达与B（ a） P诱导浓度和诱导时间呈正相关,随着诱导浓度的增加和暴露时间的延长,表达量逐步上调;超氧化物歧化酶（ SOD）、过氧化氢酶（ CAT）和谷胱甘肽过氧化物酶（ GPx）活性均随B（ a） P诱导时间的延长而逐步升高,其中SOD酶活性随B（ a） P浓度的增加出现抑制, CAT和GPx酶活性则与B（ a） P浓度呈正相关。     

Increase in plasma total antioxidant capacity of grazing Japanese Black heifers and cows in forestland in Japan

Blood total antioxidant capacity (TAC) has become a key bio‐marker for animal health. Forest‐grazing cattle are known to forage various native plants that have high TAC. This study evaluated differences of plasma TAC between forest‐grazing (FG) and pasture‐grazing cattle (PG). Experiment 1 monitored the plasma TAC levels of 32 Japanese Black cattle. The level in PG did not change throughout the grazing period. However, that in FG, which increased from summer, was significantly higher than that in PG through fall (P < 0.05). In experiment 2, we used nine Japanese Black heifers and investigated their blood antioxidant parameters and the TAC in plants that the cattle consumed in late June and September. The plasma TAC levels in FG were significantly higher than those in PG in both periods (P < 0.05). Plasma levels of lipid peroxidation in FG tended to be lower than that in PG (P = 0.098). Furthermore, the TAC levels in various species of shrubs and trees consumed by FG were higher than those in pasture grasses. Results of this study show that plasma TAC of grazing Japanese Black cattle in forestland increase from summer through fall.     

Effects of in vitro exposure to ozone and/or hyperoxia on superoxide dismutase, catalase, glutathione and lipid peroxidation in red blood cells and plasma of rainbow trout, Oncorhynchus mykiss (Walbaum)

In aquaculture, ozone is used as a disinfectant. In its production, extensive amounts of oxygen are formed resulting in hyperoxic conditions in culture units. Both ozone and hyperoxia have the potential to be toxic via pro‐oxidant mechanisms and to activate antioxidant defence systems in cultured species. To eliminate systemic effects, blood of rainbow trout, Oncorhynchus mykiss (Walbaum), was exposed in vitro for 5 min to ozone/hyperoxia or hyperoxia, and changes in antioxidant defences and lipid peroxidation were measured after exposure. Ozone exposure caused severe damage in red blood cells (rbc) detected as increased lipid peroxidation and oxidized glutathione (GSSG) levels in both plasma and rbc. Oxygen exposure alone increased intracellular lipid peroxidation and GSSG levels 10 min after exposure and was not evident in the plasma at any time. Ozone, but not oxygen exposure, decreased reduced glutathione (GSH) levels in plasma, and the changes were negatively correlated with increased lipid peroxidation in rbc, indicating that extracellular GSH has a dynamic role in the protection of rbc from direct oxidation by ozone. Both ozone and hyperoxic conditions increased superoxide dismutase (SOD) activity in rbc 3 and 6 h after exposure. In contrast, catalase activity was only increased 10 min after oxygen exposure, suggesting other catalase activation mechanisms rather than enzyme induction. The recovery of lipid peroxidation and GSSG levels in rbc after hyperoxia, but not ozone exposure, indicated a capacity to defend against hyperoxia‐produced oxidative damage, but an overwhelming of antioxidant defences by ozone in rainbow trout rbc in vitro.     

橡胶树体胚发生过程中的生理生化特性

以巴西橡胶树花药为外植体,研究了巴西橡胶树花药体胚发生过程中抗氧化酶活性和某些生理参数的变化。结果表明,橡胶树花药体胚发生过程中,SOD活性变化表现在培养30 d达到最高值,而后下降平缓;丙二醛(MDA)含量在第60天达到最高。生理参数的变化表现为可溶性蛋白含量0 d含量最高,可溶性糖的含量在50 d达到最高,据此认为,SOD和MDA对橡胶树花药体胚的诱导起主导作用,可溶性蛋白含量与不定芽的发生密切相关。     

花生非淀粉多糖和抗氧化肽同步提取技术研究

研究米曲霉和酿酒酵母混合固态发酵热榨花生粕同步提取花生非淀粉多糖和抗氧化肽,为花生粕的高值化利用提供理论基础。以发酵产物的可溶性氮浓度、1,1-二苯基苦基苯肼(DPPH)自由基清除率、羟自由基清除率和非淀粉多糖得率为考察指标,研究了菌种比例、接种量、营养盐溶液量、发酵温度、发酵时间、水浴温度和水浴时间对发酵效果的影响,确定最佳工艺条件为:菌种比例1∶2,接种量3mL,营养盐溶液添加量30mL,发酵温度33℃,发酵时间42h,水浴温度40℃,水浴时间6h。此工艺下发酵产物的可溶性氮浓度为46.32mg/mL、DPPH自由基清除率为71.90%、羟自由基清除率为96.96%、非淀粉多糖得率为4.36%。发酵产物经乙醇沉淀和超滤分离得到的花生非淀粉多糖和抗氧化肽产品具有清除自由基、抑制脂质过氧化、金属离子螯合力和还原力等4大类抗氧化活性。