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<正>禽流行性感冒(Avian influenza,AI)简称禽流感,又名真鸡瘟(Fowl plague)、真性鸡瘟、鸡疫、欧洲鸡瘟等,是由A型流感病毒(Avian Influenza Virus,AIV)引起的从呼吸系统病变到全身败血症的一种高度接触性、急性传染病。鸡、火鸡、鸭等家禽及野鸟均 相似文献
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禽流感（Avian Influenza，AI）俗称真性鸡瘟或欧洲鸡瘟，是由A型流感病毒引起的禽类全身性或呼吸器官性传染病，OIE把该病定为A类烈性传染病。禽流感病毒（A-vian influenza virus，AIV）隶属正黏病毒科流感病毒属，典型的病毒粒子为球形，直径80～120nm，有时呈丝状体等多形态，至今A型流感病毒的血凝素已发现有16种，神经氯酸酶有10种，其血清型较多，容易变异。病毒主要通过病禽的排泄物，分泌物和尸体等污染饮水和饲料，经消化道或伤口传染，易感动物包括各种家禽或野禽，例如鸡、鸭、鹅、火鸡等家禽及野鸟、水禽，海鸟等均可感染。而对家养的鸡和火鸡引起的危害最为严重，甚至威胁着人类的健康。 相似文献
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禽流感又称真性鸡瘟或欧洲鸡瘟，是家禽由流感病毒引起的一种急性、高度致死性传染病。鸡和火鸡最易感染。病毒存在于病鸡的所有体液、分泌物和排泄物中。病毒对热的抵抗力较低，普通消毒剂就可以快速将其杀死，低温冻干可存活多年。病禽及其尸体是主要传染源。通过消化道、呼吸道、皮肤损伤和眼结膜传染。病禽的蛋可带毒，常使出壳的雏鸡大批死亡。 相似文献
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禽流感过去称之为鸡瘟或真性鸡瘟，以区别于曾称之为亚洲鸡瘟的鸡新城疫病。这是在十九世纪末就已经发现可在鸡群中引起鸡只大批死亡的一种严重传染病。到上世纪七十年代证实它是由一类A型流感病毒引起，才正式改名为禽流感。 相似文献
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鸡高致病性禽流感免疫操作中应注意的事项 总被引：1，自引：0，他引：1
1流行病学
禽流感又称真性鸡瘟或欧洲鸡瘟，是由流感病毒引起的一种急性、高度致死性传染病，鸡和火鸡最易感染。病毒存在于病鸡的所有体液、分泌物和排泄物组织中，对热的抵抗力较低，普通消毒剂就可以快速将杀死，低温冻干可存活多年。病禽及其尸体是主要传染源，通过消化道、呼吸道、皮肤损伤和眼结膜进行传染。病禽的蛋可带毒，常使出壳的雏鸡大批死亡。其他年龄的鸡发病率和死亡率都很高，常常给大、中、小型鸡场带来毁灭性打击。 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