浑善达克沙地公路综合防护技术及其效益分析

浑善达克沙地省际通道综合防护体系包括:公路沙害快速治理和沙源控制技术及耐风沙植被建植技术。阻沙带、固沙带改变了风沙流结构,降低了输沙强度,增加了地表粗糙度,有效的起到了削弱风速,阻截流沙,控制沙丘前移,保持地表稳定的作用;建立稳定的耐风沙植被是持久固沙和生物防护的核心;首次大规模使用“固沙网”专利技术产品用于公路快速固沙保苗,实践证明采用固沙网与柳条立式沙障的组合固沙技术对于快速固沙和植被恢复的作用更加显著;并提出了公路沙害快速治理技术体系与配套的技术措施。项目实施过程中3年投入产出比为1∶2.6,通过公路沙害治理工程的实施,稳定防护10年的经济总收益为4.67亿元;如将挖方路堑段砂质陡坡用植物固沙措施代替传统石砌护面墙技术推广至其它工程,效益更为显著。该项目技术研究与工程建设紧密结合,操作性强,能快速有效治理荒漠化地区公路沙害,总结出了沙区公路、铁路沙害的治理模式,对于我国荒漠化治理有推广应用价值。     

椰心叶甲的天敌——椰心叶甲啮小蜂在田间扩散距离测定

采用软皮尺实地丈量,使用OP3000水准仪测量和使用地球定位仪———Gps72测定椰心叶甲的天敌———椰心叶甲啮小蜂在田间释放后的扩散距离及向上扩散的高度。结果表明:椰心叶甲啮小蜂在田间有一定的向周边扩散能力,在田间释放后20d,啮小蜂可向周边扩散10~50m。7个月后,最远可扩散6 km。扩散距离与风向有关,东北风较多情况下,向西南扩散最远距离可达6060 m,向东北方向扩散仅仅890 m。啮小蜂在田间扩散呈椭圆形状向各方向扩散,顺风面扩散距离远、范围较大。     

Study on Synergistic Effect of VA5 Immunopotentiator on Pigeon NDV Inactivated Vaccine

This study was designed to evaluate the synergistic effect of VA5 immunopotentiator on pigeon ND4416 inactivated vaccine.160 healthy pigeons were randomly divided into four groups,including ND4416 strain inactivated vaccine group (NDV group),ND4416 strain inactivated vaccine and immunopotentiator (VA5) mixed group (NDV+VA5 group),La Sota inactivated vaccine group (La Sota group) and normal saline as the control group (C group),to assess their vaccine efficacy against virulent pigeon NDV by serological analysis and animal testing.Pigeons sera were collected at different time points after immunization and measured the HI antibody titer of each group.The results showed that VA5 immunopotentiator significantly improved the serum antibody level of pigeons immunized with pigeon Newcastle disease inactivated vaccine (P<0.05).In addition,comparative test of spleen lymphocyte transformation was conducted at various time points after immunization.The results indicated that VA5 effectively stimulated the lymphocyte transformation of immune pigeon.Pigeons in each groups were challenged with ND4416 strain at the 30th,90th and 180th d after immunization.The results presented that the NDV+VA5 group had 100% protection rate and higher than La Sota group.The duration of immunization test showed that the antibody titer of NDV+VA5 group reached peak 11.20log₂ at the 21st d,remained 7.50log₂ at 180th d,and the protection rate remained 100% at 180th d.It indicated that VA5 immunopotentiator sustained the immune duration of pigeon NDV vaccine up to 180 d.Moreover,the in vitro detoxification test results suggested that VA5 immunopotentiator reduced the in vitro detoxification cycle of pigeons after challenge.Overall,this study suggested VA5 immunopotentiator could significantly improve the immune efficacy of pigeon Newcastle disease inactivated vaccine,which provided a basis for further enhancing the efficacy of Newcastle disease vaccine,as well increased experimental data for the application of immunopotentiators.     

Research Progress of Canine Coronavirus and Feline Coronavirus

Canine coronavirus (CCoV) and feline coronavirus (FCoV) belong to α-genus coronavirus of coronavirus family,porcine transmissible gastroenteritis virus (TGEV),porcine epidemic diarrhea virus (PEDV) also belong to the same genus.Genetic evolution analysis showed that different genotype of the virus could produce new variant strains through gene recombination,which caused great obstacles to the diagnosis and control of the disease.β-genus coronaviruses include bovine coronavirus (BCoV),canine respiratory coronavirus (CRCoV) and severe acute respiratory syndrome coronavirus (SARS-CoV).Among them,CRCoV has the highest homology with BCoV,but there are great differences in genomic structure,pathogenic mechanism and infection symptoms between this kind of coronavirus and α-coronavirus.CCoV and FCoV are widely spreading around the world,characterized by high morbidity and low mortality.Due to the characteristics of RNA virus and the influence of environmental selection pressure,the viruses continue to mutate and evolve,and new virulent strains appear one after another.The virulence of feline infectious peritonitis virus (FIPV) is greatly enhanced,some specific point mutations in the virus genome change the cellular tropism against the host.The pathogenesis of the virus mainly depends on the antibody-dependent enhancement (ADE) induced by virus infection.The epidemiological investigation and prevention and control of CCoV and FCoV should not only rely on the single factor of vaccine immunity,but also comprehensively consider the virulence of the virus,environmental conditions,pet self-immune resistance, and so on.The identification of CCoV and FCoV should be based on clinical symptoms,combined with routine hematological examination,serum biochemical examination and laboratory diagnosis techniques to prevent false positive and false negative results.     

生长激素基因多态性与生产性能关系的最新研究

生长激素是一种具有广泛生理功能的蛋白肽激素,尤其对动物的生长发育具有重要作用。研究GH基因功能区的突变对其蛋白功能的影响,以及对哺乳动物生长发育的影响,具有重要的理论意义和实践意义。因此在生产中探讨GH基因多态性与生产性能的关系,从而达到提高动物生产水平的目的,成为人们关注的重要课题。     

传染性法氏囊病病毒JS株VP2基因真核表达载体的构建及其应用

应用RT-PCR方法从鸡传染性法氏囊病病毒(IBDV)JS株中扩增出VP2基因,并克隆入T-easy载体。序列测定分析结果表明IBDVJS株的VP2基因与国际标准强毒株的核苷酸序列同源性达98%,氨基酸序列同源性达99%以上。随后将VP2基因克隆入真核表达载体pcDNA3.1/zeo( ),构建成功真核表达质粒pcD-VP2,pcD-VP2体外转染COS-1细胞,能在COS-1细胞中表达。利用pcD-VP2质粒进行动物实验,结果表明雏鸡免疫14d后在体内可检测到特异性抗体,pcD-VP2的真核表达质粒二次免疫诱导鸡产生对IBDV强毒攻击的保护率为67%,这一结果提示VP2基因具有重要开发应用价值。     

徐州地区鸭传染性浆膜炎的病原分离鉴定及药敏试验

从徐州地区临床疑似鸭传染性浆膜炎发病鸭中分离到细菌21株，通过细菌形态、培养特怔、生化试验和动物试验，鉴定为鸭疫里默氏杆菌菌株，对不同地区分离到的21株菌进行了24种常用抗菌药物的药敏试验，结果该24个菌株对头孢类药物、红霉素、链霉素、妥布霉素、新霉素、氯霉素、泰乐菌素、痢特灵等几种药物敏感性较高，对喹诺酮类、强力霉素、丁安卡那霉素、林肯霉素、庆大霉素、氟苯尼考、利福平、复方新诺明等均不同程度地产生了耐药性。不同地区分离到的鸭疫里默氏杆菌对不同抗菌药的敏感程度存在较大差异性，研究结果为该地区鸭传染性浆膜炎的药物防治提供了很好的理论依据.     

禽流感病毒H9亚型血凝素特异性单克隆抗体的制备和鉴定

以常规方法纯化H9亚型禽流感病毒，制备了两株分泌抗禽流感病毒H9亚型血凝素特异性单克隆抗体的杂交瘤细胞11A5和1182，其上清ELISA效价均为1：10^4，腹水效价为1：10^7和1：10^6，HI效价上清分别为8、7log2，腹水效价均为15log2。采用HI方法证明其对禽流感病毒H9亚型的特异性，通过Western blot方法证明两株单抗都针对H9亚型禽流感病毒HA1蛋白。     

J亚群禽白血病病毒(ALV-J)ELISA检测方法的建立

利用抗J亚群禽白血病病毒（ALV—J）囊膜蛋白特异性单克隆抗体JE9，建立了检测ALV—J env抗原抗体免疫复合物的ELISA方法。应用该方法检测SPF鸡血清、鸡抗禽流感H9亚型阳性血清、鸡沙门氏菌阳性血清、鸡腺病毒阳性血清、鸡新城疫阳性血清．结果均为阴性，无交叉反应；抗ALV—J阳性血清与ALV—J特异性单克隆抗体JE9能相互阻断；ALV—J阳性血清经酸处理后，ELISA检测的D490差值明显下降。对部分攻毒鸡血清样本及田间ALV—J阳性血清样本进行电镜观察，可见ALV—J样病毒粒子及ALV—J样免疫复合物。经与间接免疫荧光（IFA）检测ALV—J env抗体结果比较表明，建立的ELISA方法与IFA方法两者具有较好的群体符合率，群体符合率为8／9。这些结果表明，本研究建立的ELISA方法在ALV—J的诊断中具有很好的应用前景。     

鸡胚胎原始生殖细胞的体外培养

旨在对影响鸡胚胎原始生殖细胞（PGCs）体外培养、传代过程的各种影响因素进行探讨。将分离到的19期鸡胚胎生殖腺的PGCs在以鸡胚成纤维细胞（CEF）为饲养层，添加细胞因子的培养体系中进行培养、传代。经冷冻保存的PGCs在添加细胞因子的培养体系中能增殖，并具有分化能力。从细胞形态、集落形态、增殖生长能力、核型检测、碱性磷酸酶测定等方面对培养过程中的鸡胚胎PGCs进行检测。结果表明，采用传至3代的CEF为饲养层，多次离散法进行传代所获得的5代鸡胚胎PGCs不但能有效维持PGCs的未分化状态和正常二倍体核型，也具有其作为多能性胚胎干细胞的一系列特征。