肉鸡腹水综合征发病机理研究进展

肉鸡腹水综合征(ascites syndrome, As),因其给肉鸡饲养业所造成的巨大经济损失,而倍受国内外学者和肉鸡饲养者的关注。20世纪90年代有人把AS与肉鸡猝死综合征、髋部结痂综合征并列为未来肉鸡饲养业需要研究解决的3种新病,过去人们对AS的病因和发病机理都有不十分清楚,影响了对该病的防治。近年来,在调查清楚病因的基础上,国内外研究人员对AS的发病机理进行了广泛深入地研究。笔者认为,AS的发病机理已经越来越清楚和明确。本文根据笔者掌握的资料,对AS的发病机理研究进展情况作一简要阐述。     

浅谈鸡腹水综合征的防治

1概述及主要症状 肉鸡腹水综合征（ascites syndrome,AS）是世界肉鸡业面临的三大危害最严重的营养代谢病之一．占肉鸡损失的25％。AS是以明显的腹水、右心扩张、肺充血、肺水肿以及肝脏的病变为特征。这种特征性症状腹水是在肺、心、肝和肾等内脏的病理损伤基础上发生的,因而称之为腹水综合征。     

肉用仔鸡腹水综合征研究进展

肉鸡腹水综合征(AS),又称腹水症、雏鸡水肿病、高海拔病、心衰综合征和肺高压综合征,是主要发生于快速生长期肉仔鸡的一种常见代谢性疾病,以明显腹腔积水、肺瘀血水肿和心脏扩张肥大、衰竭为特征.本病广泛分布于世界各地,被认为是影响肉鸡养殖业的主要疾病之一,与肉鸡猝死综合征和腿病一起称为危害肉鸡的三大疾病[8].……     

肉用仔鸡腹水综合征的发病原因及控制方法

肉用仔鸡腹水综合征（AS），又称肉鸡肺动脉高压综合征（PHS），是影响世界肉鸡养殖业的主要疾病之一。本病主要发生在冬春季节快速生长的４～７周龄肉鸡，以血液粘度升高、肺动脉高压、右心衰竭、肝脏淤血和腹腔积液为主症。目前认为，本病的发生与肉鸡生理机能本身、鸡舍环境低温、氨气、生长过快、饲料营养浓度太高、疫苗反应、呼吸系统疾病、曲霉菌病、遗传性过敏等因素有关。１肉仔鸡腹水综合征的发病原因肺动脉高压是AS发病机理的核心，引发的原因主要有：１．１缺氧１．１．１鸡舍通风不良，导致缺氧在冬季，鸡舍的通风换气受影响…     

肉鸡腹水综合征（AS）及其防治

肉鸡腹水综合征（BroilerAscitesSyndrome，AS）又称腹水症、毒脂综合症、高山病、高空病、禽水肿、鸡水肿病、充血性心脏病、腹腔积水、水肛等，是一种代谢性疾病，以肉鸡腹部发生严重的腹水为特征，多发生于生长迅速发育良好的肉用仔鸡群中。AS已成为目前常见的多发病之一，造成较大的经济损失。据估计，全世界每年因本病造成的损失大约为10亿美元，已引起世界养禽业的关注。1发病情况1946年美国最早报道衣阿华州雏火鸡腹水症，最初仅发生于高海拔的国家，如南美、墨西哥和南非等。进入70年代伴随品种改良和饲养管理水平的提高，肉鸡生…     

腹水征肉鸡红细胞变化的研究

肉鸡腹水综合征(AS ascitess yndrome in broilers)又称肉鸡缺氧性肺动脉高压综合征，是以腹部膨大，腹腔内积聚大量浆液性液体和右心室扩张为特征的疾病，是造成肉仔鸡淘汰、死亡的重要原因之一。给当今世界肉鸡养殖业带来一大难题，成为影响养殖业发展的重要因素之一。该病1946在美国首次报道，其它国家也相继报道，统计表明，英国1965年该病的死亡率约为0.03％-0.04％，     

肉鸡腹水综合征研究进展

肉鸡腹水综合征 ,又称肺动脉高压综合征 ,是影响世界肉鸡饲养业的主要疾病之一。文章着重论述了肉鸡腹水综合征的病史、诱发因素、临床病理学特征以及诊断和治疗的最新研究进展 ,同时对其发病机理提出了三种假说。为进一步揭示其发病机理 ,更好地预防和治疗肉鸡腹水综合征提供了理论参考     

肉鸡腹水综合征的形态学观察

肉鸡腹水综合征(AS)严重制约肉鸡养殖业的发展。试验研究采用形态学的方法比较健康肉鸡和腹水肉鸡的差异。结果表明:与健康肉鸡相比,腹水肉鸡腹部膨大下垂、触摸有波动感、皮肤变薄发亮或呈青紫色;剖解可见腹腔内积有大量腹水、腹水呈淡黄色、伴有胶冻样渗出物;心脏体积增大、淡黄色心包液异常增多、右心室明显肥大扩张、心内膜结节状增厚、心肌松弛;肝脏肿大变硬、表面有黄色纤维样渗出物;肺严重瘀血、水肿。显微结构显示,与健康肉鸡相比,腹水肉鸡增厚的肺脏动脉管壁源于中膜平滑肌增生和外膜炎性细胞浸润。研究结果提示,在防治或深入研究肉鸡AS时,应注意从其肺血管重构所致的肺动脉高压着手,采取相应的防治措施。     

肉鸡腹水综合征对营养物质代谢规律影响的研究进展

肉鸡腹水综合征(ascites syndrome,AS)是以明显的腹水、右心扩张、肺脏充血水肿及肝脏病变为主要特征的疾病.肉鸡AS危害性巨大,由于该病受遗传、营养、环境等诸多因素的影响,其发病机制仍有许多不清楚的环节,尚无完善的防治措施.     

维拉帕米对环境低温诱发肉鸡肺动脉平滑肌细胞增殖的作用

环境低温诱发肉鸡腹水综合征(AS)发生过程中,肺血管发生明显重塑,并以肺动脉中膜增厚为主要特征。血管平滑肌细胞的数量将影响血管中膜的厚度[1]。故推测认为肉鸡肺动脉平滑肌细胞增殖在肺血管重塑过程中起着重要作用。研究认为细胞内的Ca2 是重要的细胞内第二信使,在细胞增殖过程中起着重要的作用。维拉帕米作为一种钙通道阻滞剂,可抑制Ca2 内流,使细胞内Ca2 水平降低,对肉鸡AS的发生有明显的预防作用[2]。但有关维拉帕米对环境低温诱发肉鸡AS过程中肺动脉血管平滑肌细胞增殖的作用,未见报道。增殖细胞核抗原(proliferating cell nucle…     

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。     

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。     

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。     

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。     

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.