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四川地区鸡传染性支气管炎肾病变型的诊断和防治研究 总被引：1，自引：0，他引：1
鸡传染性支气管炎(Avian Intectious Bronchitis IB)是鸡的一种急性、有高度接触性的传染病、是危害养鸡生产最严重的病毒性传染病之一。Schok和Haun(1931)首次报道了致呼吸道病变为主和成年鸡产蛋下降的鸡传染性支气管炎,Winterfield(1962)报道了鸡传染性支气管炎的肾病变型。我国邝荣禄(1982)在广东首先发现肾病变型IB。林绍义(1983)对本病进行了较为详细的研究。1988年以后我国广西、江苏、上海、新疆、北京等地相继报道了本病并分离出病毒。1992年底,四川地区部份鸡场发生该病流行,经流行病学调查、临床症状、病理变化观察和病毒的分离鉴定,本研究组在四川首次确诊了鸡传染性支气管炎肾病变型的存在。 相似文献
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<正> 鸡传染性支气管炎(IB)是由传染性支气管炎病毒(IBV)引起的一种急性、高度接触性传染病,在世界范围内广泛流行。根据临床与组织嗜性通常可分为呼吸型、肾病变型和腺胃病变型三种类型。自1995年以来,腺胃病变型IB在我国部分省(市)流行,造成巨大的经济损失,为了控制肾型、腺胃病变型IB的发生和流行,中国农业科学院哈尔滨兽医研究所研制出鸡传染性支气管炎活疫苗(D971P株),技术特点主要有以下几个方面。1.该疫苗具有自主知识产权中国农业科学院哈尔滨兽医研究所科研究员荣骏弓等从国内发病鸡群中分离到的腺胃病变型鸡传染性支气管炎病毒(IBV-D971株)并进行了系统鉴定,该成果"腺胃病变型鸡传染性支气管炎病毒的分离鉴定"于2003年1月20日通过了农业部成果鉴定,获中国农业科学院科技进步2等奖。利用该病毒(IBV-D971株)在SPF鸡胚上连续传105代,培育出 相似文献
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荣骏弓 《畜牧兽医科技信息》2003,19(11):50-50
鸡传染性支气管炎(IB)是由传染性支气管炎病毒(IBV)引起的一种急性、高度接触性传染病,在世界范围内广泛流行.根据临床与组织嗜性通常可分为呼吸型、肾病变型和腺胃病变型三种类型.自1995年以来,腺胃病变型IB在我国部分省(市)流行,造成巨大的经济损失,为了控制肾型、腺胃病变型IB的发生和流行,中国农业科学院哈尔滨兽医研究所研制出鸡传染性支气管炎活疫苗(D971P株),技术特点主要有以下几个方面. 相似文献
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荣骏弓 《畜牧兽医科技信息》2003,(11)
鸡传染性支气管炎(IB)是由传染性支气管炎病毒(IBV)引起的一种急性、高度接触性传染病,在世界范围内广泛流行。根据临床与组织嗜性通常可分为呼吸型、肾病变型和腺胃病变型三种类型。自1995年以来,腺胃病变型IB在我国部分省(市)流行,造成巨大的经济损失,为了控制肾型、腺胃病变型IB的发生和流行,中国农业科学院哈尔滨兽医研究所研制出鸡传染性支气管炎活疫苗(D971P株),技术特点主要有以下几个方面。 相似文献
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鸡传染性支气管炎（IB）是由鸡传染性气管炎病毒引起的一种急性高度接触传染性的呼吸道疾病.其特征是病鸡咳嗽、喷嚏和气管发生啰音.在雏鸡还可以出现流涕,产蛋鸡产蛋减少和质量变劣,肾病变型肾肿大,有尿酸盐沉积.该病具有高度传染性,因病原系多血清型,而使免疫接种复杂化.感染鸡生长受阻,耗料增加,产蛋和蛋质下降,死淘率增加,给养鸡业造成巨大经济损失. 相似文献
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鸡传染性支气管炎(IB)是由鸡传染性支气管炎病毒(IBV)引起的鸡的急性、高度接触性传染病，该病是以损伤气管、引起肾脏病变、母鸡产蛋量下降和产畸形蛋为特征。尤其是近年来由于IBV新的血清型不断增加和变异株的不断出现，给养鸡业造成了严重的经济损失。虽然IB疫苗的应用在一定程度上控制了本病的暴发和流行，但由于IBV血清型众多及地域之间的差异、各血清型之间的交叉保护性较 相似文献
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鸡传染性支气管炎病毒分子生物学研究进展(上) 总被引：1，自引：1，他引：0
鸡传染性支气管炎(Infections Bronchitis of chickens缩写为IB)是鸡的一种急性、高度接触性呼吸道和泌尿生殖道传染病.临诊上以气管罗音、咳嗽和打喷嚏为主要特征,幼鸡感染可致死亡,产蛋鸡群感染则导致蛋的产量和质量下降.主要侵害鸡的呼吸系统、泌尿系统、消化系统、生殖系统.传染性支气管炎病毒(IBV)属冠状病毒科,其血清型极为复杂,目前已知IBV有30多个血清型,不同血清型及变异株间抗原性差异很大,且不断变异,这就给IBV的诊断、免疫及IBV血清型分型带来很大的困难.该病对养鸡业危害极大,从而引起了国内外禽病工作者的高度重视.分子生物学研究进展(上). 相似文献
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鸡传染性支气管炎(Infectious Bronchitis,IB)是由鸡传染性支气管炎病毒(Infectious Bronchitis Virus,IBV)引起的一类急性、高度接触传染性的呼吸道疾病.IBV主要侵害鸡的呼吸系统和泌尿生殖系统,能够引起鸡的呼吸道炎症、肾脏损伤、产蛋量和蛋品质下降.IBV是国内养禽业快速... 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