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本试验旨在研究VE水平和免疫应激对雏鸡血浆中皮质酮浓度的影响。采用3×3因子设计,3个日粮处理组,3个免疫应激处理组,每个处理5个重复,每个重复12只鸡,共计540只鸡。3个日粮处理组分别为对照组（VE=0 IU/kg）、添加40 IU/kg VE组和添加100 IU/kg VE组。常规免疫3种处理方式分别为5日龄首免、8日龄首免和11日龄首免,疫苗种类和后续时间间隔均相同。试验中期,每只鸡腹腔注射大肠杆菌脂多糖（LPS）0.05 mg。结果表明,VE水平显著影响血浆皮质酮的浓度。 相似文献
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研究维生素E水平和免疫应激处理对蛋鸡血清皮质酮浓度的影响.采用3×3双因子设计,选用270只19周龄的健康白来航蛋鸡,随机分为9组,每组5个重复,每重复6只鸡.其中,3个日粮维生素E添加水平分别为0、40和100 IU/kg,3种免疫应激方式分别为不注射、肌肉注射氯化钠注射液和肌肉注射减蛋综合征(EDS)疫苗.第2次免疫应激前12 h,后24 h、72 h和120 h测定其血清中皮质酮含量.结果表明:维生素E水平和免疫应激对血清中皮质酮浓度没有显著影响.注射和疫苗应激可增加血清中皮质酮的浓度.随着维生素E水平的提高,血清皮质酮浓度达到峰值的时间推迟,并有缓和免疫应激的趋势. 相似文献
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试验旨在研究酵母硒与维生素E (VE)对蛋鸡产蛋性能、蛋品质及抗氧化性能的影响。试验使用3×3双因素设计，分别设3个硒添加水平（0、0.15、0.30 mg/kg）和3个VE水平（0、15、30 IU/kg）。选取2 700只蛋鸡随机分为9组，每组3个重复，每个重复100只蛋鸡。预试期3 d，正式试验期49 d。结果显示，酵母硒、VE及两者的交互作用对蛋鸡的平均产蛋率具有显著影响（P<0.05），并且蛋鸡的平均产蛋率和平均产蛋重均随VE和酵母硒水平上升而显著上升（P<0.05）。酵母硒和VE水平可以显著降低蛋鸡料蛋比和死亡率（P<0.05）。VE、酵母硒及两者的交互作用显著影响鸡蛋蛋白高度（P<0.05），且蛋白高度随着酵母硒和VE添加量增加而显著上升（P<0.05）。VE和酵母硒可显著改善蛋黄颜色和哈夫单位（P<0.05），但无交互作用。蛋鸡血清总抗氧化能力（T-AOC）及谷胱甘肽过氧化物酶（GSH-Px）、超氧化物歧化酶（SOD）活性随着VE和酵母硒水平的增加而显著提升（P<0.05），血清丙二醛（MDA）含量随着VE和酵母硒水平的增加而显... 相似文献
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万寿菊提取物和VE对蛋鸡抗氧化和免疫应答的影响 总被引：1，自引：1，他引：0
150日龄海兰灰蛋鸡576R,随机分为16个处理,每个处理3个重复,每个重复12只鸡.采用4×4完全随机设计,日粮中添加万寿菊提取物(MAR)(0、60、120和240 mg/kg)和VE(0、50、100和200IU/kg),研究其对蛋鸡抗氧化和免疫应答能力的影响.结果表明:120mg/kgMAR组血清SOD活性较未添加组提高了20.92%(P<0.05),240 mg/kg MAR组MDA含量降低了20.61%(P<0.05).100 IU/kg VE组GSH-PX活性较未添加组提高了25.87%(P<0.05);200 IU/kg VE组SOD活性提高了43.18%(P<0.05),MDA含量降低了24.96%(P<0.05).120 mg/kg MAR组免疫后7和14 d新城疫抗体滴度较未添加组分别提高了0.95(P<0.05)和1.03个水平(P<0.05).200 IU/kg VE组免疫后14和28 d新城疫抗体滴度提高了1.02(P<0.05)和0.70个水平(P<0.05).表明日粮中另外添加120mg/kg MAR,100和200IU/kg VE,有利于提高机体的抗氧化和免疫应答能力. 相似文献
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本试验以4种不同品系的商品蛋鸡为研究对象,探讨了长期气候应激(热暴露)和急性免疫应激(脂多糖,LPS)对其生产性能的单一或联合效应。在体液免疫活性和新生期成活率方面,这4种蛋鸡两两不同,各具特色。22周龄时,每个品系选取80只蛋鸡,随机分配到两个完全相同的人工气候室内,其中一个恒温为32℃,另一个为21℃。热应激开始后1 d,每个气候室每种品系内,一半蛋鸡静脉注射脂多糖。试验期共23 d,在此期间统计采食量、体重、日产蛋数、蛋重和蛋壳厚度等指标。结果发现,温热应激可以显著降低蛋鸡的采食量、体重、日产蛋数、蛋重和蛋壳厚度,而免疫应激只能显著降低前四者,且体重和蛋重尚属LPS处理与时间的互作效应。随着时间的逐步推移,尽管试验鸡群在经历免疫应激后能够恢复如初,但对于温热应激却不能完全耐受。连续热暴露23 d后,蛋鸡的体重、采食量和日产蛋数出现下滑。由此说明,急性LPS处理与长期高温应激对于产蛋鸡群的影响力度不同,同时,试验蛋鸡对于这些应激因素的适应机制存在差异。体液免疫活性和新生期成活率的单边或联合优势,与试验鸡群对不同应激源的颉颃反应没有必然联系,不过蛋鸡采食量的品系与高温处理互作,体重的品系、高温处理与时间互作,品系、LPS处理与时间互作,日产蛋数的品系与高温处理互作,品系与LPS处理互作等效应均显著。虽然各个品系蛋鸡的反应模式类似,但反应水平不同,由此提示,某些品系蛋鸡的应激抵抗能力异于常类。 相似文献
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文章旨在通过正交试验设计研究饲料中添加不同水平的维生素E(VE)、维生素C(VC)和大豆油对高温期蛋鸡主要生产性能的影响,从而筛选出高温下提高蛋鸡生产性能的VE、VC和大豆油的最佳水平。试验选用41周龄京粉蛋鸡810只,试验设计选用L9(34)正交表,VE(100,200,300 mg/kg)、VC(100,200,300 mg/kg)和大豆油(1%、2%,3%)均为3个水平,分为9组,每组6个重复,每个重复5个单笼,每个单笼3个蛋鸡。预试期1周,试验期为60 d,统计各组产蛋率、料蛋比和平均每日总蛋重。结果表明:高温下,对料蛋比影响最大的因素是大豆油,对产蛋率、平均每日总蛋重影响最大的因素是VE;VE 200 mg/kg或300 mg/kg、VC 100 mg/kg与大豆油2%组合的料蛋比最低;VE300 mg/kg、VC 200 mg/kg和大豆油1%或2%组合的产蛋率最高;VE 300 mg/kg、VC 200 mg/kg、大豆油2%组合的平均每日总蛋重最高,最佳组合为:VE 300 mg/kg、VC 200 mg/kg、大豆油2%。 相似文献
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由于新城疫疫苗的普遍使用和推广,典型新城疫在蛋鸡群中已无大的流行.但是,蛋鸡非典型新城疫在国内许多蛋鸡场仍不断发生,给我国蛋鸡业造成巨大损失.蛋鸡非典型新城疫的发病原因有以下几种:①鸡场野毒污染严重.鸡场环境被病原微生物严重污染,导致鸡群感染非典型新城疫.②饲养管理不当.如在用新城疫疫苗滴鼻、点眼、饮水或气雾免疫后,马上进行带鸡消毒.③疫苗本身的原因.养殖户平时使用的活疫苗,一般要经过2～3个中间商,运输途径和保存方法不正确,导致疫苗反复冻融,造成免疫效果下降.④疾病原因.大部分养殖户会根据传统的经验定期对鸡群进行免疫接种,往往不考虑鸡群的健康状况,有时会在鸡群处于非健康的状态下进行免疫接种,造成更大的应激,导致免疫效果差,甚至免疫失败. 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
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。 相似文献
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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。 相似文献
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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。 相似文献
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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. 相似文献
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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. 相似文献