断奶应激对仔猪的影响及补救措施

仔猪的断奶应激对仔猪的影响甚至对整个养猪生产过程影响都很大．只有处理好仔猪断奶后易出现的一系列问题,并且及时有效地解决,才能保证养猪的效益。笔者就困扰当前养猪生产中最大的难题——断奶应激对仔猪的有害影响以及有效的补救措施进行了阐述．旨在为养猪生产者提供参考。     

仔猪断奶应激的研究进展

在现代化的养猪生产中．仔猪早期断奶由于具有提高母猪的生产效力、满足仔猪生长的营养需要、降低饲养成本等优点,而得到广泛的推广和应用,但是由此引发的仔猪断奶应激性综合征,同时也给仔猪生长和养猪生产都带来了巨大的负面影响。本文通过对断奶应激的影响因素和断奶应激的调控措施等方面的概述,总结了仔猪断奶应激的研究进展,     

断奶仔猪腹泻的发生与防治

仔猪断奶后的腹泻是养猪生产中最普遍的一种疾病,尤其是21—35日龄早期断奶的仔猪更多见,是集约化养猪生产中比较棘手的问题,也给养猪生产带来很大的经济损失。现将断奶仔猪腹泻发生的原因和防治措施综合介绍如下,以供参考。1.发病原因1.1 断奶应激 断奶应激主要来源于心理应激(由母猪与仔猪分离引起)、营养应激(由仔猪从哺母乳转向干饲料所引起)和环境应激(由仔猪从分娩栏转到保育栏引起)三个方面,特别是营     

断奶仔猪应激期肠道健康及营养调控的研究进展

仔猪断奶后需经历环境变化、饲粮转变以及自身肠道结构与功能改变,易发生断奶应激,直接影响养猪生产的效率.因此,研究缓解断奶仔猪应激的调控措施对养猪生产具有重要意义.本文分别从肠道健康和营养调控两方面出发,对近年来关于仔猪断奶应激的调控措施进行综述,以期为进一步研究仔猪断奶应激和健康养殖提供理论依据和调控思路.     

早期断奶仔猪配合饲料配制技术的探讨

现代养猪生产中 ,已基本普及仔猪早期断奶技术 ,而早期断奶仔猪由于受心理、环境、营养应激等因素影响 ,易导致仔猪断奶后的腹泻。Ｆｕｎｄｅｒｂｕｒｋｅ等[1] 曾研究了这三种应激对 2 8日龄断奶仔猪生理和生长的影响 ,结果发现断奶应激以营养应激影响最大 ,而心理和环境应激的影响则较小。故早期断奶仔猪料的配制 ,直接关系到断奶仔猪生长及今后生产性能的发挥。1　早期断奶仔猪腹泻原因分析1 1　仔猪饲料消化吸收不良　仔猪消化吸收不良与仔猪营养消化生理特点有很大的关系。仔猪乳糖酶的活性在出生后 2～ 3周时达到顶峰 ,然后很快下降…     

应激反应对断奶仔猪腹泻的影响

断奶仔猪腹泻是养猪生产中常见疾病之一,是一种复杂的疾病群。仔猪断奶后腹泻的原因比较复杂,由于诸多应激因素的影响,导致仔猪断奶后2周腹泻的发病率高达30%。为了降低断奶仔猪腹泻发病率,提高仔猪成活率,特将断奶后诸多应激因素对仔猪腹泻的影响与防治措施总结如下,以供参考。1应激反应1.1仔猪断奶后离开母猪的精神应激。1.2仔猪由舒适的产房,特别是由保育箱迁到保育舍;由依     

断奶应激对仔猪生长和母猪繁殖性能影响的研究进展

主要阐述了伴随断奶日龄出现的断奶应激对仔猪生长过程的影响,以及早期断奶对母猪繁殖性能等方面的影响。并就早期断奶技术在降低仔猪断奶应激、改善母猪生产能力、提高养猪生产效益方面所起的作用进行了分析。     

黄芩苷对缓解仔猪免疫应激的研究

在当前的养猪生产中,早期断奶是提高养猪生产效率的重要手段。但早期断奶对仔猪的应激非常大,容易引起仔猪免疫应激而影响仔猪的健康生长。如何缓解仔猪免疫应激成为了养猪业的一大热点。黄芩苷是一种疗效确切的常用中草药,具有清热解毒、抗炎、利胆、降压、利尿等多方面的作用,能够减少炎症的发生,间接缓解免疫应激带给仔猪的危害。     

改善仔猪营养性应激的调控措施

应激是指机体对外界或内部的各种非常刺激所产生的非特异性应答反应的总和。现代养猪生产通过早期隔离断奶技术来提高母猪的年生产力，但仔猪早期断奶时，因心理、环境及营养性应激的影响，常表现为食欲差、消化功能紊乱、腹泻、生长迟滞、饲料利用率低等所谓的仔猪早期断奶综合征。在这些应激因素中，营养性的应激占很重要的原因，为保证仔猪顺利地早期断奶，解决好营养性应激是当代养猪科学与动物营养学所关注的热点问题，成为养猪成功的关键环节之一。它不仅影响仔猪的健康与发育，还严重影响以后的生长速度与健康性能。     

山楂粉对早期断奶仔猪的增重效果

仔猪断奶是养猪生产上的一个重要环节。仔猪断奶后,由于受饲料和外界环境的影响,容易造成仔猪消化不良,厌食、腹泻及其它应激症状,致使早期断奶仔猪增重缓慢。为增强和促进早期断奶仔猪的消化能力,提高增重速度,减轻应激影响,我们充分利用当地山楂果品丰富的资源,...     

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.