大骨鸡MSTN基因的表达检测

以大骨鸡为试材,采用RT-PCR法检测了MSTN基因在大骨鸡不同器官中的表达情况。结果表明,MSTN基因在大骨鸡骨骼肌中表达水平较高,在心肌、肾脏、脑、肠、舌中也有微量表达,但在肺、肝脏中未检测出MSTN mRNA,而且在14日龄时表达水平高于35和56日龄。     

基因型鹅副粘病毒NA-1株全基因组的克隆及特性分析

将本实验室分离保存的NA-1株鹅副粘病毒(GPMV)经SPF鸡胚增殖,收集鸡胚尿囊液进行病毒纯化,提取病毒基因组RNA。参考GenBank已收录的GPMVZJ1株基因组序列,设计了8对特异性引物,RT-PCR法分别特异性的扩增出病毒各基因片段,并将各目的基因片段回收纯化,克隆PGEM-T载体,转化大肠杆菌DH5α,小提质粒选取阳性克隆酶切鉴定并进行序列测定,对测定结果进行拼接得到全长cDNA序列(GenBank登录号:DQ659677)。NA-1株核苷酸比新城疫病毒(NDV)核苷酸多6个碱基,位于1644~1645nt之间,符合NDV核苷酸“六碱基原则”。序列分析结果表明,GPMVNA-1株与各地代表株核苷酸同源性81.2%~91.3%。同时根据各毒株F基因开放阅读框前389个核苷酸序列绘制出系统发育进化树,结果表明GPMNNA-1株与SF02和QY97病毒株同属于基因型,不同于基因IX型NDV的国家标准株F48E9和基因型的LaSota传统弱毒株。     

国内动物卫生风险分析研究评述

近年来由动物疫病、药残等引起的食源性疾病数量不断上升,已成为影响各国公共健康和经济发展的重要因素。为此,切实加强动物卫生风险分析工作,研究重大动物疫病风险分析概念框架,构建适合我国国情的动物疫病风险分析模型,已成为进一步提高我国重大动物疫病防控能力和动物产品安全监管水平,不断提升我国养殖业国际竞争力的一项十分重要而紧迫的任务。同时,动物卫生风险分析也是世界动物卫生领域一种新的工作理念和管理模式,是制定动物卫生政策和开展畜产品国际贸易的一项基础性工作。近年来,国内专家学者不断将国际动物卫生风险分析的最新研究成果和国内动物卫生现状相结合,逐步探讨具有本土化特色的动物卫生风险分析的理论和相应的技术方法,其研究结果对国际动物卫生领域的不断完善和发展起到了促进作用。本研究对近年来不断涌现的动物卫生风险分析的相关研究文献进行汇总分析,以明晰该方向研究工作的进展和动态,并探析动物卫生风险分析领域存在的问题,以期为补充和完善该领域的研究工作提供一定的基础。     

Clinical and immunological heterogeneity of canine subepidermal blistering dermatoses with anti‐laminin‐332 (laminin‐5) auto‐antibodies

Laminin‐332 (laminin‐5) is a basement membrane heterotrimeric protein composed of alpha‐3, beta‐3 and gamma‐2 laminin chains. Laminin‐332 polypeptides are targeted by auto‐antibodies in human patients with mucous membrane (cicatricial) pemphigoid or, more rarely, subepidermal vesicular diseases that resemble epidermolysis bullosa acquisita (EBA) or bullous pemphigoid (BP). The objectives of this report were to characterize the clinical, histopathological and immunological characteristics of nine dogs with auto‐antibodies targeting laminin‐332. Immunological investigations consisted of direct immunofluorescence (IF), indirect IF with intact and salt‐split canine gingival, and salt‐split normal or laminin‐332‐deficient human skin, immunoblotting with purified human laminin‐332 and immunoblotting with recombinant NC1 domain of human collagen VII. All dogs exhibited varying degrees of skin blistering and ulceration associated with microscopic subepidermal vesiculation with or without inflammatory cells. Indirect IF established that circulating IgG auto‐antibodies bound the dermal side of salt‐split canine lip and human skin. In five dogs, IgG variably recognized the basement membrane of laminin‐332‐deficient human skin (three dogs negative, two dogs positive). In all nine dogs, IgG auto‐antibodies detected purified human laminin‐332 by immunoblotting. In two dogs, additional targeting of collagen VII‐NC1 was present. These observations establish laminin‐332 as a novel basement membrane antigen in dogs with autoimmune blistering diseases with variable clinical phenotypes. The names ‘acquired junctional epidermolysis bullosa’, ‘anti‐laminin‐332 mucous membrane pemphigoid (MMP)’ and ‘mixed auto‐immune subepidermal blistering dermatosis’ are proposed for dogs with clinical signs reminiscent of EBA, MMP or BP respectively.     

阳光玫瑰与浪漫红颜葡萄特性比较

近几年,阳光玫瑰葡萄种植效益明显突出于其它品种,发展势头迅猛,但由于品种特性,需要精品栽培,管理不好容易造成品质不佳,售价不高,去年,浪漫红颜葡萄又走进种植户视野,很多农户就种植阳光玫瑰还是浪漫红颜犹豫不决,本文就浪漫红颜葡萄与阳光玫瑰葡萄的相同、相似特性,浪漫红颜葡萄优于阳光玫瑰葡萄的特性,阳光玫瑰葡萄优于浪漫红颜葡萄的特性3方面进行了详细比较,并针对性提出建议,对指导农户品种选择有着较好的影响。     

Targeted Knock-in of a Fluorescent Protein Gene into the Chicken Vasa Homolog Locus of Chicken Primordial Germ Cells using CRIS-PITCh Method

In chickens, primordial germ cells (PGCs) are effective targets for advanced genome editing, including gene knock-in. Although a long-term culture system has been established for chicken PGCs, it is necessary to select a gene-editing tool that is efficient and precise for editing the PGC genome while maintaining its ability to contribute to the reproductive system. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) and CRISPR-mediated precise integration into the target chromosome (CRIS-PITCh) methods are superior as the donor vector is easier to construct, has high genome editing efficiency, and does not select target cells, compared to the homologous recombination method, which has been conventionally used to generate knock-in chickens. In this study, we engineered knock-in chicken PGCs by integrating a fluorescent protein gene cassette as a fusion protein into the chicken vasa homolog (CVH) locus of chicken PGCs using the CRIS-PITCh method. The knock-in PGCs expressed the fluorescent protein in vitro and in vivo, facilitating the tracking of PGCs. Furthermore, we characterized the efficiency of engineering double knock-in cell lines. Knock-in cell clones were obtained by limiting dilution, and the efficiency of engineering double knock-in cell lines was confirmed by genotyping. We found that 82% of the analyzed clones were successfully knocked-in into both alleles. We suggest that the production of model chicken from the knock-in PGCs can contribute to various studies, such as the elucidation of the fate of germ cells and sex determination in chicken.     

ST贴壁细胞悬浮驯化及应用

为将ST贴壁细胞通过自主驯化,使其能在ST-S细胞无血清培养基中悬浮生长且能稳定传代,在摇瓶中实现高密度生长,并应用于猪伪狂犬病毒(PRV)悬浮培养,经ST-A低血清培养基适应培养,对一株贴壁的ST细胞进行了无血清的全悬浮驯化,并将PRV在悬浮细胞中连续盲传培养。结果显示:ST悬浮细胞能在无血清培养基中传代,培养48 h至第3代后,所能达到的最终细胞密度为3.00×10^(6 )cells/mL以上;PRV连续培养至第5代,毒价可达到109.0 TCID50/mL。结果表明,用专用培养基可使ST贴壁细胞实现悬浮驯化,并可应用于PRV悬浮培养。本研究为获得高密度ST悬浮细胞和提高PRV增殖效率奠定了技术基础。     

全株玉米青贮饲养肉牛最佳日粮组合模式研究

对肉牛常用饲料进行营养价值评定,并选择36头6～24月龄西杂肉牛分4组分别采食不同组合日粮,试验期63～68 d.结果表明,不同饲料之间蛋白含量、有效降解率和有效能含量存在较大的差异.肉牛代谢体重干物质采食量与日粮粗蛋白含量之间存在极显著正相关关系,日增重随代谢体重采食量的增加呈直线增加,经济效益随肉牛日增重的增加而增加.以青贮 秸秆 0.5 kg肉牛浓缩料、青贮 秸秆 2 kg肉牛精料补充料、青贮 牧草 0.5 kg肉牛浓缩料、青贮 牧草 2 kg肉牛精料补充料日粮组合分别饲养西杂肉牛,日增重(ADG)分别为0.66 kg、0.90 kg、0.92 kg、1.08 kg;体况评分(BCS)分别增加0.33分、0.42分、0.56分、0.69分;日盈利分别为3.44元、4.22元、4.70元、4.41元.说明,以全株玉米青贮 优质牧草粗饲料组合饲养肉牛,再补饲含高蛋白和能促进肉牛生长及提高纤维饲料消化率的瘤胃微生物所必须矿物质的肉牛浓缩料或肉牛精料补充料,可使肉牛达到较好的增重,并获得较高的收益.     

加强兽药监管,生产安全畜产品

兽药是一种特殊商品,在畜业生产中被广泛使用,如使用不当不仅影响动物疫(疾)病防治效果,而且通过食物链间接影响人类的健康和生命。