Do swallows (Hirundo daurica) use the visual cue of hatchling down‐feathers to discriminate parasite alien nestlings?

Egg recognition is a variable but common anti‐parasitism defense among different species of birds with brood parasites. In contrast, nestling recognition is rare. Very few studies have found nestling recognition in brood parasite hosts and determined the rejection mechanism behind this behavior. Hosts may use the number of hatchling down‐feathers to reject parasite nestlings. We tested whether hatchling down‐feathers is a visual cue for the red‐rumped swallow, a host that can recognize and reject parasite nestlings. Our results indicated that red‐rumped swallows do not recognize foreign nestlings based on hatchling down‐feathers. The closed nest structure and hatchling morph may explain the absence of such a mechanism. None of the rejection mechanisms found in previous studies could explain the nestling recognition in swallows. Olfactory cues, tactile cues, or other visual cues, except for single nestling or hatchling down‐feathers, may provide nestling recognition in red‐rumped swallows. More study is needed to evaluate these possibilities.     

广东地方品种鸡J亚群禽白血病病毒分离鉴定及遗传进化研究

为了解广东地方品种鸡J亚群禽白血病病毒(ALV-J)净化情况,利用ALV-p27特异性抗原检测、病毒分离、PCR扩增和全基因组测序分析等方法,从广东某地方品种鸡群中分离鉴定出1株ALV-J,命名为GDYH-Y1。全基因组序列分析表明,GDYH-Y1分离株的LTR、gag和pol基因相对保守,而3′UTR和gp85基因变异较大,其中gp85基因与ALV-J参考毒株序列同源性仅为87.5%~92.8%,3′UTR区的rTM出现大量碱基缺失,遗传进化分析表明GDYH-Y1分离株与美国白羽肉鸡源分离株ADOL-7501亲缘关系最近。研究为广东地方品种鸡ALV-J净化效果提供数据参考,为分析广东地方品种鸡ALV-J毒株的分子特征和变异趋势提供了重要的数据资料。     

采用SP法检测商品蛋鸡感染J亚群禽白血病病毒对产蛋性能的影响

本研究属世界上首次报道J亚群禽白血病病毒感染对蛋鸡产蛋性能的影响。尸体剖检观察到产蛋鸡的生殖系统发育不良，表现为卵巢、输卵管幼稚型，输卵管粗细不均。组织病理学观察，发现卵巢组织中有大量的胞浆内充满球形嗜酸性颗粒的骨髓瘤细胞。用特异性抗J亚群禽白血病病毒(ALV—J)囊膜糖蛋白gp85的单克隆抗体检测不产蛋鸡的卵巢、输卵管等待检的组织切片，均检出病毒阳性抗原。结果表明ALV—J的感染造成产蛋鸡卵巢、输卵管发育不良，是蛋鸡不产蛋的直接原因。     

表达H5亚型禽流感病毒HA基因的重组马立克氏病病毒的构建

采用聚合酶链反应或反转录聚合酶链反应扩增出H5亚型禽流感病毒(AIV)的HA基因、网状内皮增生症病毒的长末端重复序列(LTR)、马立克氏病病毒(MDV)Rispens CVI988毒株基因组的sorf 1和sorf 2序列、两端带loxp位点的lac/smGFP标志基因,构建含这些基因的转移载体质粒pMHA;以MDV Rispens CVI988毒株的基因组DNA和PMHA质粒DNA共转染鸡胚成纤维细胞(CEF),采用同源重组方法将LTR、lac/smGFP和HA基因插入到MDV基因组,获得重组病毒rMDV-HA/GFP;以cre介导的同源重组去除lac/smGFP标志基因,再转染CEF,获得仅带LTR启动子和HA基因的重组MDV疫苗毒株rMDV-HA.rMDV-HA仍保留了MDV RispensCVI988疫苗毒株的复制特点,并能稳定表达AIV的HA.     

禽腺联病毒全基因组的克隆及感染性病毒的拯救

为了克隆禽腺联病毒(Avian adeno-associated virus,AAAV)全基因组用于构建基因转移载体研究,以鸡胚致死孤儿病毒(CELO)作为辅助病毒与AAAV共接种SPF鸡胚进行AAAV的增殖,将AAAV约4.7kb双链基因组DNA与pCR2.1载体连接,构建了含AAAV全基因组的重组质粒pAAAV并进行了测序。序列分析表明,AAAV YZ-1株的基因组为4684bp,两端具有141bp的末端倒置重复序列和Rep蛋白结合位点特征序列,与GenBank中收录的AAAV DA-1株和VR-865株的核苷酸序列同源性分别为95.0%和92.2%。将pAAAV质粒转染CELO病毒感染的鸡胚肝细胞系,获得了感染性AAAV病毒粒子,结果证明克隆的AAAV基因组中存在与病毒复制和包装相关的正确关键序列,可用于重组AAAV载体的构建。     

Molecular identification of the vaccine strain from the inactivated oil emulsion H9N2 low pathogenic avian influenza vaccine

In order to control the H9N2 subtype low pathogenic avian influenza (LPAI), an inactivated vaccine has been used in Korea since 2007. The Korean veterinary authority permitted the use of a single H9N2 LPAI vaccine strain to simplify the evolution of the circulating virus due to the immune pressure caused by the vaccine use. It is therefore important to determine the suitability of the vaccine strain in the final inactivated oil emulsion LPAI vaccine. In this study, we applied molecular rather than biological methods to verify the suitability of the vaccine strain used in commercial vaccines and successfully identified the strain by comparing the nucleotide sequences of the hemagglutinin and neuraminidase genes with that of the permitted Korean LPAI vaccine strain. It is thought that the method used in this study might be successfully applied to other viral genes of the LPAI vaccine strain and perhaps to other veterinary oil emulsion vaccines.     

鸡尿酸盐沉积临床病理学实验研究

将２５６只３５日龄迪卡鸡随机分为对照、高蛋白Ⅰ、高蛋白Ⅱ、高钙和肾衰组,通过人工复制尿酸盐沉积病例,对禽痛风进行临床病理学研究。结果：（１）正常鸡血浆中约有０．１０７ｍｍｏｌ／Ｌ的尿酸与大分子（蛋白质）结合,当血浆尿酸浓度升高时,结合尿酸的浓度不变,游离尿酸水平升高;（２）高蛋白饲料使饮水增多,血浆尿酸、ＮＰＮ升高（Ｐ＜０．０１或Ｐ＜０．０５）,而肾脏菊糖清除率与对照组（３．２７２μｇ／ｋｇ．ｍｉｎ－１）差异不显著（Ｐ＞０．０５）,剖检未见痛风病变;（３）日粮高钙使采食量下降,增重降低,血浆钙、尿酸、ＮＰＮ升高（Ｐ＜０．０１或Ｐ＜０．０５）,肾菊糖清除率（２．７０９μｇ／ｋｇ．ｍｉｎ－１）与对照组差异不显著（Ｐ＞０．０５）,但死亡鸡中３／１１见肾和输尿管内有较多尿酸盐沉积;（４）肾脏损害使血浆尿酸、ＮＰＮ升高（Ｐ＜０．０１或Ｐ＜０．０５）,Ｎａ＋、总蛋白降低（Ｐ＜０．０５）,肾菊糖清除率显著低于对照组（Ｐ＜０．０５）,死亡鸡中１９／２７有明显肾脏肿大、肾和输尿管内沉积大量尿酸盐。     

鸡大肠杆菌iss基因的克隆测序及原核表达

本实验对鸡大肠杆菌O2血清型菌株进行iss基因克隆测序，并在此基础上设计出两对套式引物，分别对含信号肽Miss基因序列和不含信号肽Miss基因序列进行扩增，并与原核表达载体pGEX-6p-1连接进行原核表达。iss基因克隆测序的结果与两组国外发表Miss基因序列进行比对，其同源性达100％。SDS—PAGE鉴定显示融合蛋白获得了较理想的表达，融合蛋白分子量分别约为36kD和33kD。     

Emerging viral zoonoses: frameworks for spatial and spatiotemporal risk assessment and resource planning

Spatial epidemiological tools are increasingly being applied to emerging viral zoonoses (EVZ), partly because of improving analytical methods and technologies for data capture and management, and partly because the demand is growing for more objective ways of allocating limited resources in the face of the emerging threat posed by these diseases. This review documents applications of geographical information systems (GIS), remote sensing (RS) and spatially-explicit statistical and mathematical models to epidemiological studies of EVZ.Landscape epidemiology uses statistical associations between environmental variables and diseases to study and predict their spatial distributions. Phylogeography augments epidemiological knowledge by studying the evolution of viral genetics through space and time. Cluster detection and early warning systems assist surveillance and can permit timely interventions. Advanced statistical models can accommodate spatial dependence present in epidemiological datasets and can permit assessment of uncertainties in disease data and predictions. Mathematical models are particularly useful for testing and comparing alternative control strategies, whereas spatial decision-support systems integrate a variety of spatial epidemiological tools to facilitate widespread dissemination and interpretation of disease data. Improved spatial data collection systems and greater practical application of spatial epidemiological tools should be applied in real-world scenarios.