硒缺乏对鸡血清组胺和5-羟色含量的影响

为探讨硒缺乏对鸡血清中组胺和5-羟色胺浓度变化的影响,将40只鸡随机分为低硒试验组（饲喂低硒日粮0．032mg／kg）和正常对照组（硒含量为0．229mg／kg）。分别在30、45、60和75日龄断头处死进行取样,用ELISA法对雏鸡血清中组胺和5-羟色胺浓度进行检测和对比分析。结果表明：缺硒组血清中组织胺和5-羟色胺浓度与对照组差异极显著（P〈0．01）,缺硒组不同日龄间差异极显著（P〈0．01）。在整个试验期内,缺硒组血清中硒含量和组胺浓度呈时间-效应关系;随日龄增加,缺硒组5-羟色胺浓度逐渐升高,在60日龄时达高峰而后降低,而对照组在60日龄后则趋于平稳。缺硒刺激肥大细胞脱颗粒,释放炎性介质组胺,使血清中浓度升高。但5-羟色胺属中枢神经递质,严重缺硒引起神经损伤,使其分泌受抑,含量降低。     

缺Se对雏鸡血清组胺水平及空肠H2R mRNA表达的影响

将40只1日龄雏鸡随机分成低Se试验组(日粮Se含量0.032 mg/kg)和正常对照组(日粮Se含量0.229mg/kg),分别在30、45、60和75 d断头处死取样,用ELISA法检测组胺浓度及半定量RT-PCR法测定空肠2型组胺受体(H2R)mRNA表达水平.结果表明,血清组胺水平在对照组与缺Se组及缺Se组组间比较差异均极显著(P<0.01);Se缺乏时鸡空肠H2R mRNA表达水平呈升高趋势,对照组与缺Se组及缺se组组间比较差异极显著(P<0.01);在整个试验期间,缺Se组血清Se含量与组胺浓度及H2R mRNA表达水平呈时间-效应关系.缺se刺激肥大细胞脱颗粒,使血清中组胺浓度和空肠H2R mRNA的表达水平升高,可能对硒缺乏引起的空肠组织损伤具有保护作用.     

氧化应激在硒缺乏致鸡胰岛β细胞功能损伤中的作用

为探讨氧化应激在硒缺乏致鸡胰岛β细胞功能损伤中的作用,1日龄海兰白蛋鸡200只,随机分为两组,缺硒组饲喂低硒日粮(硒含量为0.032 mg/kg),对照组饲喂正常日粮(硒含量为0.282 mg/kg).分别于30,45,60及75日龄采取全血和胰腺,检测血清和胰腺中抗氧化酶(GSH-Px、SOD、CAT)活性,GSH、MDA含量,放射免疫法检测血清和胰腺中胰岛素和C肽含量,荧光法测定全血和胰腺中硒的含量.结果表明:缺硒组全血和胰腺中硒含量呈下降趋势,血清和胰腺中GSH-Px、T-SOD、CAT活性、GSH含量均低于对照组,MDA含量高于对照组,同时血清胰岛素、C肽含量下降,胰岛C肽及胰岛素分泌贮备减少,均具有统计学意义(P<0.01,P<0.05).缺硒可使鸡血清和胰腺内抗氧化酶活性下降,胰岛β细胞功能降低,表明氧化应激是硒缺乏致鸡胰岛β细胞功能受损的主要原因.     

硒和铬对蛋鸡脂质代谢及鸡蛋硒含量的影响

本试验旨在研究在蛋鸡日粮中添加酵母硒和吡啶羧酸铬及其互作对蛋鸡生产性能、脂质代谢及鸡蛋品质的影响.选用320只45周龄海赛克斯蛋鸡随机分为4组,每组4个重复,每个重复20只鸡,在基础口粮中分别添加0 mg/kg吡啶羧酸铬(Ⅰ组)、0.4 mg/kg吡啶羧酸铬(Ⅱ组)、0.5 mg/kg酵母硒(Ⅲ组)、0.4 mg/kg吡啶羧酸铬+0.5 mg/kg酵母硒(Ⅳ组),预饲1周,试验从46周龄持续到50周龄,试验期5周(35 d).结果表明,Ⅲ、Ⅳ组产蛋率极显著提高,料蛋比极显著降低(P<0.01).Ⅱ、Ⅳ组血清总胆固醇含量极显著降低(P<0.01),Ⅲ、Ⅳ组血清高密度胆固醇含量极显著升高(P<0.01).Ⅱ、Ⅲ、Ⅳ组蛋黄中的胆固醇含量与Ⅰ组差异极显著(P<0.01).Ⅲ、Ⅳ组与Ⅰ、Ⅱ组相比,鸡蛋硒含量极显著升高(P<0.01).Ⅲ、Ⅳ组在试验开始到第2周末鸡蛋硒含量极显著升高(P<0.01),从第2周末到第5周末,硒含量基本稳定,4个组均进入平台期.结果显示,吡啶羧酸铬极显著降低了血清及蛋黄中的胆固醇含量.酵母硒极显著提高了产蛋率,降低了料蛋比,并降低了蛋黄中胆固醇含量,提高了鸡蛋中的硒含量.同时添加吡啶羧酸铬和酵母硒极显著提高了产蛋率,降低了料蛋比,并降低了血清及蛋黄中的胆固醇含量,提高了血清中高密度胆同醇含量和鸡蛋中的硒含量.     

缺Se对雏鸡血清组胺水平及空肠H_2R mRNA表达的影响

将40只1日龄雏鸡随机分成低Se试验组（日粮Se含量0.032 mg/kg）和正常对照组（日粮Se含量0.229mg/kg）,分别在30、45、60和75 d断头处死取样,用ELISA法检测组胺浓度及半定量RT-PCR法测定空肠2型组胺受体（H2R）mRNA表达水平。结果表明,血清组胺水平在对照组与缺Se组及缺Se组组间比较差异均极显著（P〈0.01）;Se缺乏时鸡空肠H2R mRNA表达水平呈升高趋势,对照组与缺Se组及缺Se组组间比较差异极显著（P〈0.01）;在整个试验期间,缺Se组血清Se含量与组胺浓度及H2R mRNA表达水平呈时间-效应关系。缺Se刺激肥大细胞脱颗粒,使血清中组胺浓度和空肠H2R mRNA的表达水平升高,可能对硒缺乏引起的空肠组织损伤具有保护作用。     

日粮不同硒水平对2～3月龄肉兔生长性能、抗氧化指标和肉质的影响

本文探讨了日粮不同硒水平对2～3月龄新西兰肉兔生长性能、抗氧化指标和肉质的影响.选用2月龄体重无显著差异的生长肉兔100只,随机分成5组,每组20个重复,在基础日粮中添加不同水平的硒(0、0.15、0.30、0.45和0.60 mg/kg),预试期7 d,正试期23 d.结果表明:在初始体重无显著差异的情况下,日粮不同硒水平娃著影响平均日增重(ADG)(P=0.019 4),0.15和0.30 mg/kg添加组显著高于对照组(0 mg/kg)(P<0.05),日粮不同硒水平对料重比(F/G)影响显著(P=0.040 1),0.15和0.30 mg/kg添加组显著低于对照组(P<0.05);日粮不同硒水平对肝脏、血清和肌肉谷胱甘肽过氧化物酶(GSH-Px)活性有显著或极显著影响(P<0.05或P<0.01);对肝脏和血清超氧化物歧化酶(SOD)活性有显著影响(P<0.05);对肝脏过氧化氰酶(CAT)活性影响显著(P=0.043 4);对肝脏和肌肉丙二醛(MDA)含量影响显著(P<0.05);对血清总抗氧化能力(T-AOC)影响显著(P=0.037 6).日粮不同硒水平对肌肉失水率影响显著(P=0.032 5),0.15 mg/kg添加组显著低于对照组和0.60 mg/kg添加组(P<0.05).日粮不同硒水平对肌肉滴水损失影响显著(P=0.004 2),肌肉剪切力受日粮不同硒水平影响显著(P=0.028 5),各添加组均显著低于对照组(P<0.05).日粮添加硒可以提高肌肉硒含量.综合本试验结果,2～3月龄肉兔日粮中硒的适宜添加量为0.15 mg/kg.     

母牛补饲维生素E和硒对新生犊牛生长和免疫的影响

本试验选择年龄、胎次、体况评分、顸产期相近的中国荷斯坦奶牛40头,随机分成2组,一组自由舔饲维生素E富硒舔砖,一组不补饲舔砖,研究维生素E(VE)和硒对新生犊牛生长和免疫的影响.试验期90 d,从预产前60 d到产后30 d.结果表明,试验组母牛血清中VE的含量在产后12 h显著高于对照组(P<0.05),血清中硒的含量在产前30 d和产后12 h高于对照组,差异极显著(P<0.01).试验组母牛分娩后12 h,血清中IgG、IgM的含量,初乳中IgM、IgG、IgA的含量都显著高于对照组(P<0.05).试验组犊牛出生后12 h,血清中VE和硒含量极显著高于对照组(P<0.01),IgG、IgA的含量高于对照组,差异显著(P<0.05).试验组犊牛初生体质量和体尺显著高于对照组(P<0.05),30日龄体质量和体尺高于对照组,差异极显著(P<0.01).试验组犊牛的发病率比对照组降低了50%.     

高铜对雏鸡脑组织一氧化氦含量和一氧化氮合酶活性的影响

1日龄艾维菌肉鸡健雏360羽,随机分为6组,分别喂以对照组日粮(10.89 mg/kg Cu)和高铜日粮(100 mg/kg Cu,高铜Ⅰ组;200 mg/kg Cu,高铜Ⅱ组;400 mg/kg Cu,高铜Ⅲ组;600 mg/kg Cu,高铜Ⅳ组;800 mg/kg Cu,高铜Ⅴ组)6周,观察高铜对雏鸡脑组织和血清一氧化氮(N0)含量及一氧化氮合酶(NOS)活性变化的影响,探讨高铜对雏鸡脑组织的损伤机理.高铜Ⅱ、Ⅲ、Ⅳ和Ⅴ组脑组织和血清NO的含量较对照组显著或极显著升高(P<0.05或P<0.01).NOS的活性随日粮铜含量的升高而升高,各高铜组脑组织NOS的活性较对照组极显著升高(P<0.01);高铜Ⅱ、Ⅲ、Ⅳ和Ⅴ组血清NOS的活性较对照组显著或极显著升高(P<0.05或P<0.01).日粮铜水平在200 mg/kg及以上时,脑组织和血清NO的含量和NOS的活性随日粮铜的含量升高而升高,脑组织因氧化而受损.     

日粮中添加高水平纳米硒对蛋鸡肝脏硒含量及抗氧化能力的影响

选取288只42周龄健康农大三号商品蛋鸡,随机分为6个组,每组设4个重复,在基础日粮中以亚硒酸钠的形式添加硒0.3 mg/kg;其余各组以纳米硒的形式分别添加硒0.3、0.5、2.5、5.0、10.0 mg/kg.试验期为60 d.结果显示:试验至30 d,添加0.5～10.0 mg/kg纳米硒能显著提高肝脏硒的含量,添加纳米硒能显著提高T-AOC活性(P<0.05),极显著提高T-SOD活性(P<0.01).试验至60 d,添加2.5～10.0 mg/kg纳米硒能极显著提高GSH-Px活性,添加0.5～10 mg/kg极显著降低NO含量(P<0.01).结果表明,日粮中添加高水平的纳米硒能提高蛋鸡肝脏的抗氧化能力.     

高铜对雏鸡脑组织氧化状态的影响

1日龄艾维茵肉鸡健雏360羽,随机均分为6组,分别喂以对照日粮(10.89 mg/kg)和高铜日粮(Cu 100 mg/kg,高铜Ⅰ组;Cu 200 mg/kg,高铜Ⅱ组;Cu 400 mg/kg,高铜Ⅲ组;Cu 600 mg/kg,高铜Ⅳ组;Cu 800 mg/kg,高铜Ⅴ组)6周,观察高铜对脑组织氧化状态的影响.高铜Ⅱ、Ⅲ、Ⅳ和Ⅴ组脑组织MDA含量升高,与对照组比较差异显著或极显著(P<0.05或P<0.01);脑组织铜-锌-超氧化物歧化酶(Cu-Zn-SOD)和谷胱甘肽过氧化物酶(GSH-Px)的活性,高铜Ⅰ、Ⅱ组显著或极显著高于对照组(P<0.05或P<0.01),高铜Ⅲ、Ⅳ和Ⅴ组较对照组极显著降低(P<0.01);高铜Ⅱ、Ⅲ、Ⅳ和Ⅴ组脑组织羟自由基活性升高,与对照组比较差异显著或极显著(P<0.05或P<0.01).同时,血清的MDA含量及Cu-Zn-SOD和GSH-Px的活性变化与脑组织一致.结果表明,日粮铜水平在400 mg/kg及以上时,脑组织的抗氧化功能受损.     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.