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<正>鸡肾型传染性支气管炎(肾型IB)是由肾型鸡传染性支气管炎病毒(肾型IBV)所引起的鸡的一种以肾脏病变为主的高度接触性病毒性传染病,它可引起雏鸡死亡。产蛋鸡产蛋量和蛋的质量下降。 相似文献
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鸡传染性支气管炎(IB)是由传染性支气管炎病毒(IBV)引起鸡的一种急性、高度接触传染病毒性传染病。临床上依据发病特点和病理特征,分为呼吸道型、肾型和腺胃型三种病型,其中肾型传支是鸡传染性支气管炎中死亡率最高的一种病型。 相似文献
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鸡传染性支气管炎是由冠状病毒科冠状病毒属的鸡传染性支气管炎病毒引起急性、高度接触性传染病。鸡传染性支气管炎病毒具有多血清型和多组织嗜性,主要有嗜呼吸道型、嗜肾型、嗜生殖器官型、嗜消化道型等。 相似文献
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鸡肾型传染性支气管炎是一种对鸡危害严重的急性、高度接触性传染病,它是由鸡传染性支气管炎病毒(Infectiousbronchitis virus,IBV)中嗜肾组织的病毒株引起的〔2〕,是鸡传染性支气管炎(Avian Infectious Bronchitis,IB)的一种。它能对各种年龄的鸡造成危害,特别是肉鸡,导致肉鸡 相似文献
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许兰菊 《河南畜牧兽医(综合版)》1995,(1)
鸡肾型传染性支气管炎病毒的分离与鉴定许兰菊(河南农业大学450002)鸡传染性支气管炎(IB)是由传染性支气管炎病毒(IBV)所引起的一种急性、高度接触性呼吸道传染病。肾型IB是由致肾病变毒株百肾型毒株)引起的,患鸡剖检病变以肾志白肿大、肾小管和输尿... 相似文献
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(一)鸡传支的几种表现型鸡传支全称鸡传染性支气管炎,致病原为传染性支气管炎病毒,属于冠状病毒科、冠状病毒属的病毒。鸡传染性支气管炎在临床上表现型有肾型传支和腺胃型传支、呼吸型传支,还有鸡传染性支气管炎病毒变异毒株表现型,其临床症状有一定差异。鸡传染性支气管炎对蛋鸡的生长性能造成严重影响,在 相似文献
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鸡传染性支气管炎是由冠状病毒科传染性支气管炎病毒(IBV)引起鸡的一种急性高度接触性呼吸道传染病。根据不同病毒株感染后侵害主要脏器的差异,常分为呼吸型、肾型、腺胃型、生殖型传染性支气管炎。鸡是传染性支气管炎病毒的唯一宿主,各种日龄的鸡均易感[1-2]。 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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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
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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