饲粮添加色氨酸对热应激肉鸡肝脏、肠道抗氧化能力和炎症反应的影响

本试验旨在研究饲粮添加色氨酸(Trp)对热应激(HS)肉鸡肝脏、肠道抗氧化能力和炎症反应以及相关信号通路的调节作用。选取180只健康体质量接近的18日龄雌性AA肉鸡,随机分为3个处理组,每组6个重复,每个重复10只鸡。适应性饲养3 d后,于21日龄开始进行温度控制,试验期为21 d。适温组(TN)肉鸡饲养于正常温度(23±1)℃,饲喂基础饲粮;热应激组(HS)肉鸡饲养于高温环境(34±1)℃、8 h/d,饲喂基础饲粮;热应激+0.18%色氨酸组(HS+0.18%Trp)肉鸡饲养于高温环境(34±1)℃、8 h/d,饲喂基础饲粮+0.18%色氨酸。结果表明：1)与TN组相比,热应激显著降低肉鸡肝脏谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)活性、回肠黏膜CAT和超氧化物歧化酶(SOD)活性以及总抗氧化能力(T-AOC)(P<0.05);与HS组相比,HS+0.18%Trp组肝脏CAT活性和T-AOC、空肠黏膜SOD活性和T-AOC以及回肠黏膜SOD活性显著升高(P<0.05)。2)与TN组相比,热应激显著增加肝脏白细胞介素(IL)-1β、IL-6、IL-18和肿瘤...     

日粮铬对热应激种公兔肝脏组织结构及血清抗氧化功能的影响

选用成年健康公獭兔72只,随机分为6组,每组12只,空白对照组饲喂基础日粮,分别在基础日粮中添加0.2、0.4、0.6、0.8、1.0mg/kg铬量的酵母铬,作为试验Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组日粮,在热应激条件下(獭兔饲养于人工气候仓内,气温设定为29³3℃,24h循环变温,33℃维持4h)饲养60d。结果显示,热应激条件下,在獭兔基础日粮中添加一定量的酵母铬不仅能有效降低热应激对种公兔肝脏组织的损伤,还可显著提高血清中GSH-Px和SOD活性,降低MDA含量(P<0.05或P<0.01)。结果表明,夏季高温环境下,在种公兔基础日粮中添加0.633℃,24h循环变温,33℃维持4h)饲养60d。结果显示,热应激条件下,在獭兔基础日粮中添加一定量的酵母铬不仅能有效降低热应激对种公兔肝脏组织的损伤,还可显著提高血清中GSH-Px和SOD活性,降低MDA含量(P<0.05或P<0.01)。结果表明,夏季高温环境下,在种公兔基础日粮中添加0.6¹.0mg/kg铬量的酵母铬可通过增强机体的抗氧化功能,抑制机体内自由基和脂质过氧化物的产生,保护机体肝脏组织结构完整,维持机体正常生理功能。     

中药复方对高温下蛋鸡肝脏组织抗氧化功能的影响

为研究中药复方对高温下蛋鸡肝脏组织抗氧化功能的影响,选取60周龄海兰白蛋鸡350只,随机分为7组即常温对照组、热应激对照组、中药复方1组、中药复方2组、中药复方3组、紫锥菊组、电解多维组。在试验第14、28、42、56天,空腹剖杀后取蛋鸡肝脏组织,测定其超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性及丙二醛(MDA)含量。试验结果表明,热应激状态下蛋鸡肝脏组织SOD、GSH-Px活性明显下降(P<0.05),MDA含量明显升高(P<0.05),中药和电解多维均可以提高热应激状态下蛋鸡肝脏组织抗氧化功能,且中药复方的效果优于紫锥菊和电解多维。     

中药复方对热刺激大鼠空肠热休克蛋白70的影响

为探讨中药复方的抗热应激机理,以大鼠为热应激模型,热应激条件为41℃,2 h。用Real-time PCR和ELISA方法检测了中药复方对热刺激后空肠组织中Hsp70的表达。结果显示,高温刺激后大鼠空肠组织中Hsp70的mRNA和蛋白表达均升高(P0.01),且中药组Hsp70表达高于热应激组(P0.01),说明中药复方能通过诱导Hsp70的表达来抵抗高温对机体造成的热刺激。     

甘蔗提取物对热应激大鼠肠道组织形态及肠道雌激素受体表达的影响

本试验旨在探讨大鼠日粮中添加甘蔗提取物(sugar cane extract,SCE)对热应激大鼠肠道组织形态和雌激素受体(ER)表达的影响。选用20只21日龄雌性Wistar Imamichi大鼠,采用2×2双因素(温度、SCE)设计,按体重将大鼠均分为4组,即NC组(常温饲喂基础日粮),NS组(常温饲喂SCE日粮),HC组(高温饲喂基础日粮),HS组(高温饲喂SCE日粮),常温为25℃恒温环境,高温为38℃温控环境暴露3 h,SCE日粮中添加2.16%SCE纯品,试验期42d。结果显示:(1)高温显著降低大鼠体重及肾脏指数,SCE对体重及器官指数无显著影响;(2)高温使十二指肠和空肠上皮细胞脱落,固有层暴露,添加SCE后十二指肠和空肠上皮细胞结构完整,排列整齐。(3)高温使大鼠十二指肠中ERβ显著减少,添加SCE后ERβ显著升高。综上,热应激可诱导大鼠肠道组织形态损伤,SCE对热应激大鼠十二指肠和空肠组织损伤具有一定的缓解作用,且SCE影响热应激大鼠发情期ERβ的表达。     

一种复方中药对断奶至2月龄肉兔生长发育、血清生化指标和肠道发育的影响

试验为研究复方中药对断奶至2月龄肉兔生长性能、血清指标、免疫机能及肠道发育的影响。选用体重(713±50)g断奶肉兔120只,随机分2组,分别饲喂基础日粮和添加复方中药的日粮,预试期7 d,正试期23 d。结果表明:日粮中添加复方中药能显著提高平均日增重(P0.05)和平均日采食量(P0.05),并显著降低料肉比(P0.05);能显著降低血清尿素氮含量(P0.05),显著提高血清IgG含量(P0.05)和血清总抗营养化能力(P0.05);能显著降低盲肠中大肠杆菌含量(P0.05)、提高乳酸菌含量(P0.05)。结果表明,日粮中添加复方中药能在一定程度上提高肉兔的生长性能,提高机体氮沉积,增强机体免疫力和抗氧化能力,并改善肠道微生物区系,有利于动物肠道健康。     

中药复方应激康对热应激肉鸡HSP70m RNA表达影响的研究

为了研究复方中药对热应激肉鸡肝脏HSP70mRNA表达的调控效果;试验选取120只18日龄AA+肉仔鸡,随机分为4组,即复方中药组、维生素组、纯中药组和高温对照组进行试验,试验后每组迅速宰杀3只试验鸡,取肝脏组织进行HSP70mRNA表达的检测。结果表明:高温应激后,复方中药冲剂组和纯中药冲剂组鸡肝脏中HSP70 mRNA表达显著增加,分别比高温对照组、维生素组高2.98倍、3.28倍和4.66倍、5.13倍,说明本试验复方中药可通过上调HSP70 mRNA表达,提高机体热耐受水平,达到保护细胞作用。     

急性热应激对肉仔鸡抗氧化能力的影响

旨在探索急性热应激对肉仔鸡抗氧化能力的影响。通过对试验组鸡急性热应激处理(38℃±1℃),湿度60%~70%。试验组鸡分别在热应激1h、2h、5h、10h进行心脏采血、剖杀及采样,分别测定其抗氧化指标。结果表明,高温急性处理可使肉仔鸡肝脏和血清中抗氧化指标发生改变,诱发氧化胁迫,导致机体内自由基增多,对机体造成损伤。     

紫锥菊及其复方对热应激蛋鸡抗氧化功能、蛋白酶及HSP70的影响

本试验通过观察紫锥菊及其复方对热应激蛋鸡抗氧化功能、蛋白酶及HSP70的影响,初步探讨紫锥菊及其复方抗热应激的作用机制。试验选用250只60周龄健康的海兰白蛋鸡,随机分成5个组,紫锥菊复方组、紫锥菊组、电解多维组在基础日粮中分别添加1.0%紫锥菊复方、1.0%紫锥菊、0.1%电解多维,高温组和常温组仅饲喂基础日粮。紫锥菊复方组、紫锥菊组、电解多维组和高温组的蛋鸡饲养在33℃～35℃的环境中,常温组蛋鸡环境温度为24℃～26℃。在试验14 d、28 d、42 d、56 d,采集各组鸡胃、胰腺和脾脏组织,检测胃蛋白酶及胰蛋白酶活性、抗氧化活性及HSP70含量变化。结果表明,紫锥菊复方、紫锥菊及电解多维均可恢复热应激导致的蛋鸡胃蛋白酶活性降低,同时紫锥菊复方的效果显著优于紫锥菊及电解多维（P<0.05）;紫锥菊复方和紫锥菊可显著提高热应激蛋鸡的胰蛋白酶活性（P<0.05）;紫锥菊复方能显著提高热应激蛋鸡脾脏中SOD、GSH-Px的活性（P<0.05）;紫锥菊复方、电解多维能恢复热应激蛋鸡脾脏组织T-AOC的水平;同时,紫锥菊复方及紫锥菊能改善热应激蛋鸡脾脏中HSP70的表达...     

中药复方中挥发油的检测及其对热应激小鼠肝脏中HSP70含量的研究

为探讨抗热应激中药复方主要挥发油成分和抗热应激的药效,采用气相色谱法检测了中药复方中香薷的麝香草酚含量。将60只SPF级6周龄昆明小鼠随机分为6组,分别灌胃中药复方和生理盐水,并且在灌胃后分别将小鼠在40℃恒温箱中放置0 h、1 h和3 h,建立急性热应激模型。试验结束后采集各组的肝脏组织,用酶联免疫分析测定小鼠热休克蛋白70(HSP70)和小鼠热休克转录因子(HSF)的含量。结果显示,中药复方中的挥发油提取液在8 h内均能保持稳定;同时中药复方能提高热应激小鼠肝脏中HSP70含量,并降低肝脏中HSF的水平。结果表明,中药复方可能通过HSP70和HSF的表达缓解热应激给机体带来的损伤。     

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。     

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。     

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。     

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.     

Mechanism of Action of Probiotic Function of Lactobacilli

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.     

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.