鸡病流行特点及防治措施

<正>当前我国的养鸡业发展迅速,农户进行集约化、规模化养殖已成为养鸡业发展的主旋律。然而各类鸡病的频繁发生和反复发作严重制约了我国养鸡业的健康发展,因此了解鸡病的流行规律和特点,并基于此开展有效的综合预防和防治措施,对保障我国养鸡业的健康发展,增加农民的经济收入意义重大。1鸡病的流行特点1.1鸡病种类不断增加随着养鸡业规模化、集约化水平的不断提     

日粮营养调控鸡球虫病研究进展

鸡球虫病是养鸡业中危害十分严重的疾病之一。其发病率达30％－100％，死亡率达20％－80％，且发过病的鸡生长发育迟缓（索勋和李国清，1998）。因此．控制球虫病成为影响养鸡业发展的关键因素之一。目前，主要采用化学药物和生物免疫法控制该病的发生。由于免疫控制法受各种条件限制，因此，防治鸡球虫仍以化学药物为主。     

论鸡传染病的治疗

养鸡业的迅速发展，特别是近些年来，集约化养鸡业的发展，带动和促进了我国鸡病研究的进步和发展。鸡病防治和研究的成果明显增多，水平提高，不少研究成果已达到国际先进水平。但在生产实践中，我国鸡病的问题仍十分突出。鸡病防治的总体水平与先进国家相比还有相当大的差距。     

蛋鸡猝死综合症的诊治

鸡的猝死综合症又称急性死亡综合症，多发于肉鸡。本病在英国、澳大利亚、东欧、加拿大、日本、美国等国家和地区广泛存在。近几年，随着我国养鸡业的发展，鸡只存栏量的不断增加，养鸡规模的不断扩大，一些营养代谢病也随之而来，特别是鸡的猝死综合症的发生率逐年提高，目前已成为严最危害我国养鸡业发展的最重要新病之一，给养鸡业造成了较大的经济损失。令年春季锦州市一养坞等业户所饲养的蛋鸡发生了本病，现将有关情况介绍如下：     

鸡球虫病流行情况调查与综合防治

鸡球虫病是现代集约化养鸡业中最为常见、多发和危害极大的肠道寄生性原虫病，其防治困难，发病率为50％～70％，死亡率严重时高达80％，给养鸡业造成了极大的经济损失。     

鸡球虫病药物防治时存在的问题与对策

鸡球虫病是一种对养鸡业危害很大的原虫病，集约化养鸡场是球虫病暴发的最适宜场所，其病死率达40％～80％。集约化养鸡业尽管受到鸡球虫病的严重威胁，几十年来仍能健康发展．这完全得益于抗球虫药的保护。     

鸡球虫病的综合防治措施

鸡球虫病是由一种或多种球虫寄生于鸡肠道黏膜上皮细胞内引起的一种急性流行性原虫病。它是现代集约化养鸡业中最为常见，多发和危险极大的肠道寄生性原虫病，其防治困难，发病率50％～70％，死亡率严重时可高达80％，给养鸡业造成极大的经济损失。     

鸡舍通风 不容忽视

在我国养鸡业由原来的粗放散养正逐步转向规模化集约化，而伴随集约化而来的饲养密度大，氧气不足，有害气体增多，导致机体体质下降，呼吸道病毒病、细菌病频发等现象，也正在制约着养鸡业发展。     

当前禽病主要流行特点与防制对策的体会

近年来，随着养鸡业的规模发展，危害养鸡业的畜禽疾病也变得越来越复杂，正确了解和认识当前鸡病动态，对于及时、有效地防制禽病的发生和发展，最大限度地减少由于鸡病所带来的损失，提高养鸡业经济效益具有重大意义。现就当前禽病主要流行特点与防制对策探讨如下：     

浅谈规模化养鸡场环境控制策略

<正>近几年来,随着集约化养鸡业的迅速发展,特别是规模化养鸡场的大量兴起。我国各地鸡病尤其是一些新兴鸡病的发生和流行,给养鸡业造成了严重的经济损失。为了保证养鸡业的稳定和发展,加     

中西结合防治仔猪黄痢

仔猪黄痢又称为大肠杆菌病，主要由致病性大肠杆菌的某些血清型，如08、060、015、0141等感染而引起产后仔猪的一种急性传染病，临床上主要以腹泻、脱水和死亡率高为特征，临床对策主要以中西医结合，母仔同时治疗，收到了一定效果。     

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。     

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.     

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.