饲粮铬对热应激肉仔鸡免疫功能的影响

目的 :　研究饲粮铬源和铬水平对热应激肉仔鸡免疫功能的影响。方法 :　按 2× 5因子安排的完全随机设计 ,将处于热应激条件下的 3 78只 4w龄商品代 Arbor Acres(AA)肉公鸡随机分为 9个处理组 ,分别饲喂含铬 0 .60 mg/kg的未添加铬玉米 -豆粕型基础饲粮 (两种铬源共用0添加组作对照 )和向该基础饲粮中添加 0 .4、2 .0、1 0 .0和 2 0 .0 mg/kg铬分别源于三氯化铬(Cr Cl3)和吡啶羧酸铬的试验饲粮 2 1 d。结果 :　所有观测指标在两种铬源间均无显著差异 ;铬水平对脾重、全血异嗜性白细胞 /淋巴细胞 (H/L)、T淋巴细胞百分率、牛血清白蛋白 (BSA)的血清抗体效价和血浆环磷酸鸟苷 /环磷酸腺苷 (c GMP/c AMP)有显著影响 ,而对胸腺重和法氏囊重无明显影响。随着饲粮铬水平的增加 ,脾重在 2 0 .0 mg/kg铬组达最大 ,H/L比值在 2 0 .0 mg/kg铬组降至最低 ,T淋巴细胞百分率在 2 .0 mg/kg铬组时达到最高 ,血浆 c GMP/c AMP在 1 0 .0 mg/kg铬组时降至最低。在血清 BSA抗体效价上铬源与铬水平间有明显互作效应 ,而在 H/L、T淋巴细胞百分率和血浆 c GMP/c AMP上铬水平与时间有明显互作效应。结论 :　无机三氯化铬与有机吡啶羧酸铬均可提高热应激肉仔鸡的免疫功能 ,具有缓解肉仔鸡高温热应激的营养作用     

碱式氯化铜对平养肉鸡生长性能、饲粮中维生素E和植酸酶稳定性的影响

目的研究饲粮中添加硫酸铜(CuSO4)和碱式氯化铜(tribasic Cu chloride,TBCC)对平养肉仔鸡生长性能、饲粮中维生素E和植酸酶的氧化稳定性及铜(Cu)的混合均匀度的影响。方法试验采用2×4因子的完全随机设计,把840只1日龄AA肉公鸡随机分为7个处理组,每组6个重复,每个重复20只。分别饲喂玉米-豆粕型基础饲粮(含Cu10.20mg/kg)和在基础饲粮基础上分别以CuSO4和TBCC形式添加100、150和200mg/kgCu的饲粮。试验期21d。结果添加200mg/kgCu的TBCC组鸡的日增重显著高于其余各组;添加100mg/kgCu的TBCC组鸡的肝脏和血浆VE含量显著高于CuSO4组,TBCC组饲粮中VE含量明显高于CuSO4组;TBCC组饲粮中植酸酶活性有高于CuSO4组的趋势;TBCC组鸡肝脏中Cu含量低于CuSO4组;TBCC组饲粮中Cu的混合均匀度好于CuSO4处理组。结论饲粮添加TBCC比CuSO4更能有效促进平养肉仔鸡的生长,更能减少饲粮中VE的氧化,生物安全性明显高于CuSO4。     

富硒蛋鸡硒水平的研究

在蛋鸡饲料中添加有机硒 ,通过生物转化可以提高鸡体的硒含量 ,从而生产富硒鸡肉和鸡蛋。用新极谱法分别测定了富硒和对照蛋鸡的血、肉、蛋、毛及粪中的硒含量 ,测得富硒蛋鸡的硒含量分别为 4 5 1 9±4 2 1μg/L、0 2 0 6± 0 0 0 6mg/kg、0 4 15± 0 0 5 2mg/kg、1 6 6 3± 0 199mg/kg及 1 349± 0 2 39mg/kg ,分别为对照蛋鸡的 4 8、1 6、3 8、5 0及 31倍。     

类黄酮物质对蛋鸡抗氧化和脂质代谢的影响

目的 :　观察茶多酚 ( TP)和大豆黄酮 ( SD)对蛋鸡抗氧化状况和脂质代谢的影响。方法 :　 2 70只 2 8w褐壳海赛克斯产蛋鸡随机分为 9组 ,第 1组饲喂基础日粮 ,第 2、3、4、5组在基础日粮中分别添加 5、1 0、2 0、40 mg/kg的 TP,6、7、8、9组在基础日粮中分别添加 5、1 0、2 0、40 mg/kg的 SD。试验期 8w。结果 :　 TP或 SD可不同程度地降低蛋黄、肝脏及血浆中脂质过氧化物水平 ,对肝脏的 GSH- Px和 SOD活力影响不明显 ;蛋黄、胸肌及肝脏中的胆固醇也有不同程度地降低 ,特别是对蛋黄和胸肌中胆固醇的影响较为显著 ,对肝脏脂肪含量影响不明显 ,蛋黄甘油三酯含量随 TP添加量的增加逐渐降低。结论 :　 TP和 SD能改善蛋鸡体内及其产品中抗氧化状况 ,对蛋黄和胸肌胆固醇有降低作用。     

高温下精氨酸对一氧化氮和细胞增殖的影响

目的　探讨精氨酸对高温下血清一氧化氮 (NO)含量和淋巴细胞增殖活性的影响。方法　BALB/C小鼠 ,随机分为对照组、精氨酸补充组 [0 5 ,1 5 ,2 5 ,3 5 g/ (kg .bw) ],每组 35只 ,其中 5只为常温对照。 14d后 ,除常温对照外均放入 (41± 0 5 )℃动物高温仓热应激 12 0min ,结束后 0 ,2 ,4 ,8,12 ,2 4h共 6个时相分别眼眶采血 ,常温组在灌胃第 3,7,11,14d时采尾血。观察指标测定血清NO浓度、淋巴细胞增殖活性。结果　 (1)在常温下补充精氨酸后第 3d各实验组血清NO含量最高 ,第 7d后基本稳定 ,补充组各个时间点都高于未补充组 ,其中补充精氨酸 0 5 g/(kg .bw)组各个时间点明显高于其他补充组。 (2 )热应激后补充 0 5和 1 5 g/ (kg .bw)及未补充组血清NO浓度有先下降 (0～ 2h最低 )而后上升 ,4～ 8h基本稳定。而补充高浓度精氨酸的两组〔2 5和 3 5 g/ (kg .bw)〕热应激后持续上升 ,而且在 12h内 ,血清NO含量明显高于低浓度的两组和对照组。 (3)在热应激下补充精氨酸的各组刀豆蛋白(ConA)刺激指数高于对照组 ,补充精氨酸的各组 ,以 1 5 g/ (kg .bw)时ConA刺激指数达到最大。热应激后 ,小鼠淋巴细胞增殖活性受到抑制 ,其中 4～ 8h最低。结论　高温环境应激下小鼠对精氨酸的需要量增加 ,而血清NO含量的变     

吡哆素L-2-吡咯烷酮-5-羧酸酯对大鼠的生殖毒性

目的　研究吡哆素L 2 吡咯烷酮 5 羧酸酯对大鼠的生殖毒性。方法　雄鼠 80只 ,雌鼠 12 4只随机分 4组 ,溶剂对照组 ,3个剂量组吡哆素L 2 吡咯烷酮 5 羧酸酯分别为 4 0 0、80 0和 16 0 0mg/kg。雄鼠交配前连续给药 6 0d ,交配期间继续给药 ;雌鼠交配前连续给药 14d ,交配后给药至妊娠第 14天 ;分别观察生殖毒性试验指标。结果　 4 0 0mg/kg组无明显毒副反应 ,80 0mg/kg组有个别鼠出现后肢麻痹 ,16 0 0mg/kg引起雌雄大鼠后肢麻痹 ,消瘦。吡哆素L 2 吡咯烷酮 5 羧酸酯 16 0 0mg/kg使雄鼠的交配率下降 5 0 % ,有统计学显著性。 80 0mg/kg组生育鼠 7只 ,16 0 0mg/kg组未生育 ,对雄鼠的生育率有统计学显著影响。 80 0mg/kg组雄鼠的精子数为 (5 9 4 0± 2 1 71)× 10 5,16 0 0mg/kg组雄鼠的精子数为 (0 4 0± 0 14 )× 10 5。 80 0mg/kg组活胎数为 (8± 3)只 ,16 0 0mg/kg组无受孕鼠。结论　吡哆素L 2 吡咯烷酮 5 羧酸酯在本实验条件对SD大鼠无致畸性 ,无作用剂量为4 0 0mg/kg ,发育毒性的无作用剂量小于 4 0 0mg/kg。     

维生素E对辐照小鼠胸腺、脾淋巴细胞数及脾淋巴细胞转化反应的影响

小鼠分别饲以基础饲料及基础饲料添加维生素E50mg/kg和500mg/kg饲料4周。然后一次全身照射400radX线,分别于照射后第6天,第14天处死,计脾与胸腺细胞数并测定脾淋巴细胞转化反应。结果表明:基础饲料组小鼠脾和胸腺细胞数较维生素E添加组明显减少(P<0.01);维生素E添加组小鼠脾T、B淋巴细胞转化反应较基础饲料组明显增高(P<0.01),且高剂量维生素E添加组的T淋巴细胞转化反应亦显著高于低剂量组(P<0.01)。     

以含锰超氧化物歧化酶基因表达评价肉鸡对不同形态锰源的生物学利用率

目的　通过两个试验研究确定心肌细胞线粒体中MnSOD的基因表达指标是否能更快、更敏感、更恒定地监测出肉仔鸡对不同形态锰源间生物学利用性的差异。方法　试验 (一 )将 5 4 6只商品代 1日龄AA肉公鸡按 4× 4两因子安排的完全随机设计分为 13个处理组 ,每组 6个重复笼 ,分别饲喂不添加锰的食用玉米 -豆粕型基础饲粮 (对照组 )或以无机硫酸锰、弱络合强度的蛋氨酸锰E、中等络合强度的复合氨基酸锰B及强络合强度的复合氨基酸锰C形式添加 0、6 0、12 0、180mg kg锰的试验饲粮 ,试验期 2 1天。 2 1日龄每个重复笼选取 3只与平均体重相近的鸡屠宰 ,立即取出心脏、左侧腿跖骨 ,分析组织锰浓度、心肌细胞线粒体中MnSOD活性及其基因表达。试验 (二 )将 2 70只商品代 1日龄AA肉公鸡随机分为 5个处理组 ,每组 6个重复笼 ,分别饲喂不添加锰的食用玉米 -豆粕型基础饲粮 (对照组 )及分别在对照组饲粮中添加 12 0mg kg锰的 4种锰源试验饲粮。分别于第 7、14、2 1日龄用与试验一相同的方法进行屠宰、组织样品的采集与制备及分析。结果　试验 (一 )中 2 1日龄肉鸡的跖骨灰锰含量、心肌锰含量和心肌细胞线粒体中MnSOD活性均受到饲粮添加锰水平的显著影响 (P =0 0 0 0 1) ,根据这三项指标与饲粮添加锰进食量的多元线性回?     

不同剂量纳米氧化铜对肉鸡血清和组织中铜含量的影响

选180羽1日龄健康AA肉仔鸡,随机分为6组,每组设3个重复。第1,2,4,6组分别以硫酸铜、氧化铜、纳米氧化铜、纳米铜的形式在基础日粮中添加铜8 mg/kg,3组和5组以纳米氧化铜形式在基础日粮中分别添加铜4 mg/kg和16 mg/kg,试验期42 d,研究不同剂量纳米氧化铜对肉鸡血清和组织中铜含量的影响。结果表明,与1、2组相比,4、5组血清铜浓度增加(P<0.05);试验至第14 d,添加纳米氧化铜显著提高肉鸡血清锌含量(P<0.05),提高肝脏锌含量(P<0.05);试验至28 d,添加纳米铜组胫骨锌含量显著提高(P<0.05)。     

纳米硒对肉鸡生长和抗氧化的影响

目的:研究纳米硒和亚硒酸钠对肉鸡生长和抗氧化的影响。方法:岭南黄雌雄混合雏780羽按试验要求分为13组,每组4个重复,每个重复15羽。将纳米硒和亚硒酸钠两种硒源分别以0.1、0.2、0.3、0.4、0.5、1.0mg/kg六个硒水平添加到基础日粮中,配制成12种试验日粮,基础日粮作对照。结果:(1)亚硒酸钠在0.2～0.5mg/kg添加水平肉鸡生长处于高峰平台,1.0mg/kg硒添加水平肉鸡生长显著低于0.2～0.4mg/kg硒添加水平。纳米硒添加1.0mg/kg,肉鸡生长仍然保持在高峰平台。硒添加浓度在0.1～0.3mg/kg时,亚硒酸钠和纳米硒对肉鸡生长无显著差异;硒添加浓度在0.4～1.0mg/kg时,纳米硒组肉鸡生长显著高于亚硒酸钠组(P<0.05)。(2)硒添加浓度在0.1～0.4mg/kg时,两种硒对GSH-Px活性和全血硒无显著差异(P>0.05);在0.5和1.0mg/kg硒水平上,纳米硒组GSH-Px活性和全血硒显著高于亚硒酸钠组(P<0.05)。(3)硒添加浓度在0.1～0.3mg/kg时,两种硒源对T-AOC、MDA和活性氧的影响无显著差异;硒浓度在0.4～1.0mg/kg硒时,纳米硒组T-AOC显著高于亚硒酸钠组(P<0.05),MDA和活性氧显著低于亚硒酸钠组(P<0.05)。结论:纳米硒用于肉鸡的Weinberg剂量-效应的最适剂量范围宽于亚硒酸钠,高剂量添加时比亚硒酸钠具有更强的营养生物学作用,对肉鸡的安全性更高。     

Chromium supplementation can alleviate negative effects of heat stress on egg production,egg quality and some serum metabolites of laying Japanese quail

This study was conducted to determine the effects of Cr (chromium picolinate, CrPic) supplementation at various levels (0, 200, 400, 800 or 1200 microg/kg of diet) on egg production, egg quality and serum concentrations of insulin, corticosterone and glucose in laying Japanese quail (Coturnix coturnix japanica) reared under conditions of heat stress (32.5 degrees C). Laying Japanese quail (n = 150; 45 d old) were divided into five groups of 30 birds. The quail were fed either a control diet containing 965 microg Cr/kg diet or the control diet supplemented with 200, 400, 800 or 1200 microg of Cr/kg diet. Increased supplemental chromium increased body weight (P = 0.05, linear), feed intake (P = 0.05, linear), egg production (P = 0.01, linear) and also improved feed efficiency (P = 0.01, linear). Increased supplemental chromium linearly increased egg weight (P = 0.01), eggshell thickness, egg specific gravity (P = 0.05) and Haugh unit (P = 0.01). Serum insulin concentration increased linearly (P = 0.01), whereas corticosterone and glucose concentration decreased linearly (P = 0.05) as dietary chromium increased. The best results were obtained with 1200 microg Cr/kg diet, and chromium supplementation at such a level can be considered to be protective management practice in a quail diet, reducing the negative effects of heat stress.     

铬对大鼠肥胖基因表达及血糖血脂的影响

目的 :　证实铬对肥胖基因表达和体重的影响及与血糖、血脂的关系。方法 :　将80只大鼠按体重随机分为 8组 ,分别为基础饲料对照组、基础饲料加铬组 (不同剂量的葡萄糖酸铬 )、高脂饲料对照组、高脂饲料加铬组 (不同剂量的葡萄糖酸铬 ) ,每周称重 1次 ,并于第 8周末断头取血 ,用放射免疫的方法检测血中的瘦素 ,用酶法检测血糖、血脂等指标 ,同时称取肝、脾、肾及睾丸等脏器 ,计算脏 /体比值。结果 :　加铬组与对照组相比 ,瘦素水平显著降低 (P<0 .0 5 )。血糖、总胆固醇 (TC)、甘油三酯 (TG)显著降低 (P<0 .0 5 ) ,高密度脂蛋白胆固醇 (HDL - C)显著升高 (P<0 .0 5 )。结论 :　铬对大鼠体重的影响不大 ,但可抑制肥胖基因的表达 ,同时具有降低血糖、TC、TG和升高 HDL- C的作用     

纤维-螯合剂降低鸡蛋胆固醇的实验研究

为了评价纤维-螫合剂降低鸡蛋胆固醇含量的效果,采用京白3系母鸡128只(22周龄),随机分为4组,分别喂基础饲料(CD)、添加4％纤维饲料(FD)、添加4％螫合剂饲料(SD)、添加2％纤维和2％螫合剂饲料(FSD)。喂饲60天后,各组鸡蛋胆固醇含量分别为3.9±0.28、3.5±0.30、3.4±0.30、3.2±0.20mg/g,FSD组比CD组减少17.9％(P<0.01)。实验期间,各组平均蛋重量和饲料消耗相近(P>0.05),而FSD组产蛋率为每只鸡(0.37±0.22枚/日),饲料效率(0.21±0.11kg蛋/kg饲料)明显高于其它组(P<0.01),比CD组分别高54.2％和61.5％。实验表明,纤维-螫合剂降低鸡蛋胆固醇的效果显著。     

Conjugated linoleic acid enhanced the immune function in broiler chicks

This study was undertaken to investigate the growth performance and immune responses of broiler chicks fed diets supplemented with conjugated linoleic acid (CLA). Two hundred and forty day-old Arbor Acre male broiler chicks were randomly allotted into four dietary treatments with different inclusion levels of CLA (0, 2.5, 5.0 or 10.0 g pure CLA/kg) for 6 weeks. Growth performance, lysozyme activity, peripheral blood mononuclear cell (PBMC) proliferation, prostaglandin E2 (PGE2) synthesis and antibody production were investigated. There were no significant differences in growth performance among treatments (P>0.05). Chicks fed 10.0 g CLA/kg diet produced 40 % and 49 % more lysozyme activity in serum and spleen than the control group at 21 d of age (P<0.05). Dietary CLA enhanced the PBMC proliferation in response to concanavalin A at the age of 21 and 42 d (P<0.05). Systemic and peripheral blood lymphocytic synthesis of PGE2 in chicks fed 10.0 g CLA/kg diet was significantly decreased by 57 % and 42 % compared to chicks fed control diet (P<0.05). Antibody production to sheep red blood cell and bovine serum albumin were elevated in either 2.5 or 10.0 g CLA/kg dietary treatments (P<0.05). The results indicated dietary CLA could enhance the immune response in broiler chicks, but did not alter the growth performance.     

High chromium yeast supplementation improves glucose tolerance in pigs by decreasing hepatic extraction of insulin

Twenty Landrace x Yorkshire cross pigs (body wt, 47.9+/-2.9 kg) were used to evaluate effects of dietary high chromium (Cr) yeast supplementation on plasma kinetics of glucose, insulin and C-peptide. Pigs were provided free access to either a control diet (C) containing 204 microg Cr/kg or a diet supplemented with an additional 200 microg Cr/kg as high Cr yeast (CR) for between 23 and 30 d. After overnight food deprivation, dextrose (500 g/L) was infused through a jugular vein catheter at a dose of 0.5 g glucose/kg body weight with an infusion rate of 10 g glucose/min within 6 min. High Cr yeast supplementation did not affect body weight gain or food intake. There were no differences in fasting plasma concentrations of either glucose or C-peptide, although basal plasma concentration of insulin tended to be higher in pigs fed CR (P<0.10). Plasma glucose concentrations were lower (P<0.01) at postinfusion times 5, 10, 15 and 20 min in pigs fed CR. Plasma insulin concentrations in pigs fed CR were higher (P<0.05) at 2 and 0 min before the completion of dextrose infusion. However, the increase in plasma insulin concentrations was not accompanied by a comparable elevation in plasma C-peptide concentrations. The 30-min (postinfusion) area of plasma glucose concentrations tended to be lower (P<0.10) in pigs fed CR, but there were no differences in 30-min areas of either plasma insulin or plasma C-peptide concentrations between treatments. Plasma clearance rates of glucose, insulin and C-peptide were higher and their half-lives shorter (P<0.05) in pigs fed CR. In conclusion, dietary high Cr yeast supplementation improved glucose tolerance, possibly through a decrease in hepatic extraction of insulin.     

Zinc supplementation alleviates heat stress in laying Japanese quail

The study was conducted to determine whether zinc supplementation could alleviate the detrimental effects of high ambient temperature (34 degrees C) on egg production, digestibility of nutrients and antioxidant status in laying Japanese quail. Quail (n = 180; 52 d old) were divided into six groups (n = 30/group) and were fed a basal diet or the basal diet supplemented with 30 or 60 mg of zinc (ZnSO(4). H(2)O)/kg diet. Birds were kept at 22 degrees C and 58% relative humidity (RH). At 13 wk of age, the thermoneutral (TN) groups remained at the same temperature, whereas the heat-stress (HS) groups were kept in an environmentally controlled room at 34 degrees C and 42% RH for 3 wk. Heat exposure decreased egg production in birds fed the basal diet (P = 0.001). Linear increases in feed intake (P = 0.01) and egg production (P = 0.004) and improved feed efficiency (P = 0.01) and egg quality variables (P 0.05). Results of the present study suggest that supplementation with 60 mg zinc/kg diet protects quail by reducing the negative effects of heat stress.     

高效液相色谱法测定减肥类保健食品中7种功效成分

目的 建立减肥类保健食品7种功效成分(左旋肉碱、L-茶氨酸、儿茶素、吡啶甲酸铬、番泻苷A、番泻苷B、鼠尾草酸)的高效液相色谱测定方法。 方法 样品直接用50%乙腈超声提取,采用C₁₈色谱柱分离,以甲醇-磷酸二氢钾(0.1%磷酸)水溶液为流动相,梯度洗脱,外标法定量。 结果 左旋肉碱、L-茶氨酸和鼠尾草酸在10.0～100.0 mg/L,儿茶素在1.0～50.0 mg/L,番泻苷A在0.50～10.0 mg/L,番泻苷B在0.20～10.0 mg/L,吡啶甲酸铬在2.0～50.0 mg/L内质量浓度和色谱峰面积有良好的线性关系,相关系数r≥0.9991。方法回收率为89.9%～108.0%,相对标准偏差为1.2%~6.3%,方法检出限为0.1~5 mg/kg。 结论 该方法快速,准确,灵敏,适合减肥类保健食品中7种功效成分的同时测定。     

The effects of whey protein and chromium picolinate supplementation on visceral fat and metabolic status in high-fat-fed rats

The objective of this study was to evaluate the effects of whey protein (WP) and chromium picolinate (CrPic) on body composition and metabolic status in rats fed a high-fat diet (HFD). Male Wistar rats (n = 10/group, 8 weeks old) were divided into three groups. The control group was fed a HFD (300 g fat/kg diet). The other two groups were fed the HFD plus 320 g whey protein isolate/kg diet (HFD + WP) with or without 80 mcg CrPic/kg body wt/day (HFD + WP + CrPic). After six weeks, rats were fasted, blood samples were drawn, and visceral and subcutaneous fat pads were removed and weighed. Daily food intake was not affected by treatment. Rats fed HFD exhibited significant increases in body weight, body fat and metabolic risk factors (p ≤ 0.05). Rats fed the HFD + WP showed a significant decrease in body weight, serum glucose and blood lipids, and a significant increase in insulin levels (p ≤ 0.05). Rats fed the HFD + WP + CrPic had the lowest levels in total visceral fat, triglycerides, total cholesterol and free fatty acids, and the highest insulin levels (p ≤ 0.05). Tissue concentrations of chromium (Cr) increased with CrPic supplementation (p < 0.001). The results of this study support the use of WP and CrPic supplementation to improve body composition and metabolic syndrome risk factors.