In order to investigate histo-pathological changes of chickens induced by glandular stomach(GS)type avian infectious bronchitis virus and the ultra-structure of the virus,clinical dissection,histo-pathology and electron microscopic examination were conducted over the 3 Shandong isolates(QX,DY and FC) of stomach type avian infectious bronchitis virus and the ultrastructure of the virus.The results showed that the isolates induced significant glandular stomach tissue inflammation manifested mainly in inflammatory cell infiltration in proventriculus mucosa,glandular epithelial hyperplasia,mucus and abundant necrotic,exfoliated and disintegrated glandular cells in gland lumen,monocyte infiltration and abundant vacuolation in epithelial cells.Viral particles with 80~120 nm were observed in the pathological tissues.Virus isolated via chicken embryo was too 80~150 nm in size with spherical or pear-shaped form.The virus was enveloped with 12~25 typical coronoid projections(the clustered virus has few coronoid projections),thus named as coronavirus.The study provided scientific reference for further studies and effective prevention and control of glandular stomach type avian infectious bronchitis.

In order to understand the pathogenicity of proventriculus type infectious bronchitis virus(IBV),3IBV strains(QXIBV,DYIBV and FCIBV)were used to challenge the unimmunized chickens and SPF chickens via nose,eye and mouth dripping in regression tests.In result,the post-mortem changes of chickens died from virus challenge in 10-day-old unimmunized were similar to those in 20-day-old unimmunized chickens.Both showed glandular stomach swelling,proventriculus mucosa hemorrhage and ulcer,kidney swelling and uratosis.The mortality of 20-day-old challenged chickens was somewhat higher than that of the 10-day-old challenged chickens.All the challenged SPF chickens showed clinical signs of depression,puffed feather and diarrhea,pathological changes of glandular stomach swelling,proventriculus mucosa hemorrhage and ulcer,and kidney swelling and uratosis which were similar to those in the naturally-infected birds.The result showed that clinical signs and pathological changes similar to those in the naturallyinfected birds could be reproduced using the Shandong IBV isolates.

In order to characterize the nucleotides of spike protein S genes of three Shandong isolates(Qingdao Strain QX,Dongying Strain DY and Feicheng Strain FC)of proventriculus type avian infectious bronchitis virus(IBV),and to compare the homology of their S gene nucleotides with respiratory type IBV M41 and nephric type IBV,RT-PCR was used to clone and sequence the S genes of the IBV isolates(QX,DY and FC)and the reference strain M41.The S genes of QX and DY strains were sequenced by Clustal V method,Jotun Hein method and Clustal W method respectively.The results showed that the highest homology of the S gene nucleotides of Strains QX and DY with the reference strain M41 was up to 79.3%and79.2%respectively with the least variation of 24.5%and 22.3%;the highest homology of the S gene nucleotides of Strains QX and DY with nephric type IBV Strain HD was up to 78.4%and 78.9%,both with the least variation of 22.7%.The highest homology between Strain HD of nephric type IBV and M41 was up to 80.8%.Analysis of the S gene evolution relationship indicated that the proventrivulus type IBV Shandong isolates(QX and DY)were variant strains with different tissue tropism and with significant difference from the respiratory type and nephric type IBV,and possessed an important evolution stage.

从2005年夏季以来,因为传染性法氏囊病毒野毒毒力增强,鸡舍消毒不严,环境卫生控制差,疫苗选取和使用不当,种鸡免疫程序不合理使雏鸡母源抗体低下等诸多因素导致育雏鸡发病,而且在全国较大范围内雏鸡和肉仔鸡发病呈蔓延和上升趋势.在治疗时滥用高免卵黄抗体或使用劣质高免卵黄抗体无治疗效果,更有多次因卵黄抗体污染导致鸡只死亡的病例出现.笔者将多年来对本病的预防和控制经验做一总结,并介绍一下高免卵黄抗体的制作方法,供大家参考.

分别用绿猴肾细胞和鸡胚成纤维细胞增殖鸡传染性鼻气管炎病毒NL 7784株,提纯抗原建立了检测鸡传染性鼻气管炎病毒抗体的间接酶联免疫吸附试验(ELISA).试验的最佳反应条件为:抗原最佳稀释度为1:160,酶标抗体为1:1000稀释,待检血清为1:160稀释,包被液为pH9.6的碳酸盐缓冲液,6%犊牛血清(CS)作封闭液,稀释液用含10%CS的Tween-20磷酸盐缓冲液,洗涤液用含0.5%Tween-20的磷酸盐缓冲液,抗原与抗体的最佳反应时间为30分钟,底物的反应时间为15分钟.与中和试验进行了比较,证明所建立的方法具有良好的特异性、稳定性、可重复性和较高的敏感性.

鸡白痢杆菌病是由沙门氏杆菌引起的一种多发和常发传染病,该病在近年来除了雏鸡由于经种蛋传染,引起刚出壳雏鸡大量发病死亡外,在育成期(中雏)和产蛋期也有典型的发病,与原有的在成鸡只表现隐性感染的观点不同,而出现新的发病规律.育成鸡发病死亡,蛋鸡发病后产蛋率下降,种蛋受精率和孵化率降低,健雏率降低,死胚率和弱胚率升高,污染严重时有的蛋鸡群出现零星死亡.

鸡白痢是由沙门氏菌引起的一种多发和常发传染病,该病在最近出现一些新特点:除了因经蛋传染引起刚出壳雏鸡大量发病死亡外,在育成鸡和产蛋鸡也有典型的发病,与原有的在成鸡只表现隐性感染不同,出现新的发病规律.育成鸡发病死亡;商品蛋鸡和蛋种鸡发病后产蛋率下降,种蛋受精率和孵化率降低,健雏率降低,死胚率和弱胚率高,污染严重时有的蛋鸡群出现零星死亡.

气管环组织培养(TOC)是用于传染性支气管炎病毒(IBV)分离、鉴定和血清学检查的有效方法[1].Johnson(1975)应用TOC中和试验将分离的IBV分为10个血清型[2];吕化广(1989)采用TOC、鸡胚接种增殖和血清学鉴定的联合方法诊断IBV感染的临床病例[3];李康然[4]应用TOC对广西分离的4株IBV定型,发现分别属于Holte型和Massachusetts型[4];我们曾应用TOC和鸡胚肾细胞(CEK)研究江苏分离的IBV,证明TOC比CEK更适于IBV的分离和鉴定.1994年以来我们先后从山东省的青岛等地区分离到7株IBV(H、J、SH、XJ、S5、SA和M株),经鸡胚传代、电镜观察、回归试验和干扰试验等初步鉴定为肾型传染性支气管炎病毒[5],并应用TOC对这7株IBV作了进一步鉴定,并与H120株,T株和已鉴定的南京NIBV株作了理化特性方面的比较.