猪的呼吸道疾病综合征

猪呼吸道疾病综合征（PRDC）是一种多因素引起的呼吸道疾病的总称,是由病毒、细菌、寄生虫、环境应激和猪体免疫力低下相互作用造成的。PRDC涉及多种引起呼吸道疾病的病原体,包括原发性感染疾病和继发性感染疾病。由于PRDC的发病原因的复杂性和病原体的多样化,所以集约化猪场要谨防PRDC的发生。     

猪的呼吸道疾病综合征

猪呼吸道疾病综合征(PRDC)是一种多因素引起的呼吸道疾病的总称,是由病毒、细菌、寄生虫、环境应激和猪体免疫力低下相互作用造成的.PRDC涉及多种引起呼吸道疾病的病原体,包括原发性感染疾病和继发性感染疾病.     

猪呼吸道疾病综合症的防治

猪的呼吸道疾病综合征(PRDC)是多因素引起的呼吸道疾病的总称,是由病毒、细菌、寄生虫、环境应激和猪体免疫力低下相互作用造成的。PRDC涉及多种引起呼吸道疾病的病原体,包括原发性感染疾病和继发性感染疾病。[1]猪呼吸道病是原发病原和机会感染病原共同作用的结果。不良的饲养管理条件,在引起猪呼吸道病的诸多因素中起重要作用。由于PRDC的发病原因的复杂性和病原体的多样化,所以,集约化猪场要谨防PRDC的发生。     

猪呼吸道疾病综合征的防治措施

猪呼吸道疾病综合征直接影响养猪业的经济效益,其病因复杂,涉及的病原体种类较多,与猪呼吸障碍综合征的病毒及一些相关环境因素相关联。本文从猪呼吸道疾病综合症的原发性和继发性成因入手,针对性地解决其防治措施。     

猪呼吸道疾病及其防制措施

猪呼吸道疾病多病原继发、诱发、交叉或混合感染的疾病为猪呼吸道疾病综合征(PRDC)。PRDC是1种或多种病毒、细菌、寄生虫辅以环境、营养等应激因素和猪只本身的机体抵抗力、对疾病侵袭的免疫力下降等相互作用平衡紊乱而引起混合感染。临床上常见引起的猪呼吸道疾病的病原体分为原发性病原感染和继发性病原感染2大类。原发性病原感染包括猪霉形体肺炎、猪圆环病毒2型、猪伪狂犬病病     

猪常见呼吸道传染病的诊断与治疗

近两年来,以呼吸困难、咳嗽为主要症状的猪呼吸道疾病成为养猪生产的主要问题,规模化猪场几乎都存在呼吸道疾病问题,发病率通常在30%～60%,死亡率在5%～30%,且难防难控,造成巨大的经济损失。1猪呼吸道疾病的主要病因1.1传染性病因导致猪呼吸系统疾病的病原微生物有:猪繁殖与呼吸综合征病毒、猪流感病毒、猪伪狂犬病病毒、猪呼吸道冠状病毒、多杀性巴氏杆菌、猪胸膜肺炎放线杆菌、副猪嗜血杆菌、支气管败血波氏杆菌、猪肺炎支原体等。原发性病原体首先侵入呼吸道和肺脏,破坏呼吸道的防御屏障,造成猪体呼吸道的抵抗能力下降,而后继发性病原体…     

家禽呼吸道疾病的病因分析及预防对策研究

1 家禽呼吸道疾病的病因分析 呼吸道疾病是家禽养殖中的常见疾病,会产生饲养成本增加、家禽养殖收益减少等不利影响.而根据以往的家禽呼吸道疾病的诊断与分析,病原体感染、禽舍管理不规范是家禽呼吸道疾病的主要病因.一方面,病原体感染是诱发呼吸道疾病的高危因素,养殖场所内分布的病原体会使家禽患有呼吸道疾病、出现气喘、喷嚏等临床症状.     

鸡混合型呼吸道疾病的发病原因及防制措施

<正>春季是多种疾病的高发期,特别是混合型呼吸道疾病是鸡饲养户的最大困扰,鸡混合型呼吸道疾病又称为多因子呼吸道疾病或复合病因呼吸道疾病。参与鸡的MRD形成的治病因素,除了引起呼吸道疾病的病原体(如支原体、细菌、病毒等)外,还有造成免疫抑制的病原体以及饲养管理不良、营养缺乏等因素和不利的环境因素,严重影响呼吸道病的治疗。呼吸道综合症很难用对付单个病原体的方法治疗,发生最普遍、最广泛。该类疾病主要影响鸡只的日增重,使饲料转化率降低,死亡     

鸡多病因呼吸道病及其防制对策

近年来，鸡的呼吸道疾病越来越严重，在很多鸡群占整个疾病造成损失的一半以上，造 成巨大经济损失。在各种类型的商业鸡群中，最常见的是由多种致病因子协同作用，形成很 难用对付单个病原体的方法防制的复合型呼吸道疾病。根据现代流行病学观点，此病称为多 病因呼吸道疾病（multicausal respiratory disease， MRD)或复合病因呼吸道疾病（respiratory disease of com plex etiology）。参与鸡的MRD形成的致病因素，除了引起呼吸道疾病的细 菌、支原体、病毒等病原体外，还有造成免疫抑制的病原体以及不利的环境因素，它们的存 在往往加重呼吸道病原体本身的致病作用(图1)。 1 呼吸道病原体之间的相互作用 两种或两种以上呼吸道病原体同时或先后作用于鸡呼吸道，它们之间可产生致病协同作 用（synergism），比单一病原体所致疾病严重得多。一般说来，病毒性病原体的 感染使呼吸道上皮发生损害，有时甚至是轻微的损害，都会为细菌的继发和并发感染造成良 好的机会。病毒感染、支原体和大肠杆菌3者之间相互作用，可以使呼吸道疾病更严重。仅 支原体感染鸡只能产生轻微的症状，但同时有NDV或IBV感染，则要加重。单独的大肠杆菌感 染也只产生轻微症状或没有症状，但如有支气管炎病毒存在     

猪呼吸道疾病复合症的免疫学

呼吸道病原体的控制机理许多 ,不过本文将集中讨论呼吸道免疫系统对诱发疾病及控制有关病原体最重要的各个方面     

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.