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高致病性禽流感防治技术问答 总被引：1，自引：0，他引：1
王秀荣 《畜牧兽医科技信息》2010,(3):107-108
<正>禽流感是禽流行性感冒的简称,是由A型禽流行性感冒病毒引起的一种禽类(家禽和野禽)传染病。根据禽流感病毒致病性的不同,分为高致病性禽流感(HPAI)和低致病性禽流感(LPAI)。HPAI表现为较严重 相似文献
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禽流感(AI)是由A型流感病毒(AIV)引起的禽类感染综合征。不同抗原亚型病毒感染不同易感鸟类,表现出从亚临床感染到轻度上呼吸道疾病、到产蛋量下降、到急性全身致死性疾病等多种不同程度疾病综合征。为此,禽流感常被分为高致病性禽流感(HPAI)和低致病性禽流感(LPAI)。目前公认高致病性禽流感是由A型流感病毒中的H5和H7两种亚型中的病毒引起的。患病禽常呈现急性败血性呼吸道或全身症状,产蛋率急速下降,以呼吸道症状和神经症状为特征的死亡率急剧上升,或没有任何症状猝死。高达85%以上的死亡率常常给予养禽业以毁灭性的打击,造成较大… 相似文献
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禽流感是禽的流行性感冒的简称．是由A型流感病毒引起的一种禽类传染病．根据其致病性和毒力的不同分为高致病性禽流感（HPAI）；低致病性禽流感（LPAI）以及无致病性禽流感。 相似文献
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禽流感(Avian Influence,AI)是禽流行性感冒的简称,是由正粘病毒科、流感病毒属A型流感病毒引起的禽类(家禽或野禽,亦有部分哺乳动物)的一种传染病。根据禽流感致病力的不同可分为非致病性禽流感(NPAI)、低致病性禽流感(LPAI)和高致病性禽流感(HPAI)3种。在我国,高致病性禽流感以H5N1亚型为代表,低致病性禽流感以H9N2亚型为主型。 相似文献
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<正>禽流感(Avian Influenza,AI)又称真性鸡瘟,是由正粘病毒科、流感病毒属A型流感病毒引起的一种急性、败血性传染病,几乎所有野生及家养禽类均可感染。可分为高致病性禽流感(HPAI)和低致病性禽流感(LPAI)两大类。H9N2亚型禽流感属于低致病性禽流感,但对养禽业的危害却很大,是仅次于H5和H7亚型禽流感的又一重要传染病。 相似文献
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禽流行性感冒(Avian Influenza,AI)简称禽流感,是由正黏病毒科A型流感病毒(AIV)引起的一种禽类疾病综合征.慢性或亚临床感染可使家禽的生产力严重下降,如增重减缓、产蛋量下降等;高致病性禽流感(HPAI)可造成家禽100%死亡. 相似文献
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禽流感及其防制 总被引：2，自引：0，他引：2
禽流感（Avian Influema，AI）是禽流行性感冒的简称，又名鸡瘟（Fowl plague）、真性鸡瘟、欧洲鸡瘟，是由正黏病毒科、流感病毒属的A型流感病毒引起的禽类的一种传染性疾病，以急性败血性死亡到无症状带毒等多种病症为特点。根据禽流感病毒的致病性强弱，将禽流感分为高致病性禽流感（Highly Pathogenic Avian Influenza，HPAI）、低致病性禽流感（Low Pathenic Avian Influema，LPAI）和无致病性禽流感（Naught Pathwgenic Avian Influema，NPAI）3种。高致病性禽流感已被世界动物卫生组织（OIE）和我国政府列为A类传染病。 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