高致病性猪蓝耳病的实验室诊断

采用猪繁殖与呼吸综合征病毒NSP2基因RT-PCR检测方法和猪繁殖与呼吸综合征病毒变异毒株试剂盒检测方法,对六盘水市钟山区某猪场发生的一起疑似高致病性猪蓝耳病进行实验室诊断,确诊为由猪繁殖与呼吸综合征病毒变异毒株引起的高致病性猪蓝耳病。     

北京地区不同秋眠级苜蓿品种适应性评价

对14个紫花苜蓿Medicago sativa品种在北京地区的表现进行观测,并对主要性状指标进行分析.结果表明:参试各品种秋眠级不同其春季生长速度、秋季生长速度、产草量及越冬率都有明显的差异,秋眠级高的品种生长速度快、产草量高,但越冬率低、秋眠级低的品种与之相反;地温也影响苜蓿生长速度;茎叶比与鲜干比各品种之间无明显变化,但与茬次有显著变化.     

巴马小型猪在达芬奇机器人手术系统中的麻醉管理

为探讨巴马小型猪在达芬奇机器人微创手术中的麻醉管理策略,以丙泊酚麻醉作诱导,异氟醚维持麻醉的复合麻醉方法对巴马小型猪进行全身麻醉,同时用达芬奇机器人对其分别进行心脏、肺脏、肝脏和胃的微创手术,于术前、术中及术后监测巴马小型猪动脉血气和血流动力学变化。结果各组试验猪均顺利完成手术,手术平均时间(166±34)min,麻醉时间(181±38)min,气胸(气腹)时间(122±33)min,在整个麻醉过程及苏醒过程中,各组试验猪安全平稳,未出现体动表现。由此可见,该麻醉方法可用于达芬奇机器人手术系统,且为人医临床应用中的麻醉管理奠定基础。     

2014-2018年广西6种猪主要病毒性繁殖障碍疫病流行病学调查

试验旨在了解广西猪主要病毒性繁殖障碍疫病的发生态势,为预防和控制此类疫病提供科学依据。采用RT-PCR/PCR方法对2014年3月至2018年2月采自广西的349份流产胎儿样品进行猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、猪圆环病毒2型(PCV2)、猪伪狂犬病病毒(PRV)、猪细小病毒(PPV)及猪乙型脑炎病毒(JEV)6种主要病毒性繁殖障碍疫病病原的检测并分析其阳性检出率在不同年份、季节之间的差异及病原混合感染情况。结果显示,2014-2017年,6种病原的猪场阳性率从高到低依次为JEV(36.00%)、PRRSV(16.00%)、PCV2(9.00%)、PRV(7.00%)、PPV(6.00%)和CFSV(5.00%),样品阳性检出率从高到低依次为JEV(27.06%)、PRRSV(6.18%)、PRV(5.88%)、PCV2(3.82%)、CSFV(2.35%)和PPV(2.35%)。季节因素对6种病毒性繁殖障碍疫病的发生有一定影响:JEV在夏季、秋季检出率较高,春季、冬季检出率较低;PRRSV一年四季检出率均较高,且无明显差异;PCV2在春季检出率较高,其次是夏季和冬季,秋季检出率较低;PRV在春季、冬季检出率较高,夏季、秋季检出率均为0;PPV在夏季检出率较高,其次是春季和秋季,冬季检出率为0;CSFV在冬季检出率最高,其次是夏季,春季和秋季检出率均为0。流产胎儿以单一感染为主,6种病毒均存在不同程度单一感染情况,单一感染率JEV最高(23.82%)、PCV2最低(0.59%);混合感染以双重感染为主,其中以2016年双重感染情况较多,且感染组合多样;三重感染情况较少、仅在2016年送检样品中发现1例,未发现四重及四重以上感染情况。调查结果表明,2014-2017年,JEV均有较高的阳性检出率,已成为广西部分猪场母猪流产最主要病毒性病原。PRRSV和PRV仍是目前引起广西猪场母猪流产的主要病毒性病原。     

Cloning and Sequence Analysis of N and M Genes of Avian Infectious Bronchitis Virus Guangxi Strain

To investigate genetic variation of avian infectious bronchitis virus (IBV) in Guangxi province,one strain of IBV was isolated from chicken.Two pairs of primers for amplifying the N and M genes of IBV were designed according to the sequences in GenBank.The N and M genes of the strain were amplified by RT-PCR,and they were proved to be the N and M genes of IBV by cloning,sequencing and compared with reference IBV strains published in GenBank.The results showed that the N gene from the IBV isolate consisted of 1 230 bp,coding 409 amino acids.The M gene from the IBV isolate consisted of 678 bp,coding 225 amino acids.The sequence analysis of N gene showed that it shared 87.2% to 93.3% nucleotide homologies and 90.0% to 94.4% deduced amino acid sequence homologies with IBV strains from GenBank.The M gene sequence analysis showed that it shared 83.6% to 91.0% nucleotide homologies and 82.7% to 92.9% deduced amino acid sequence homologies.The phylogenetic tree analysis showed that it was closely related to BJ and LX4 strains,and were clustered into one group;But with the distant relatives from other strains of IBV.These results suggested that the isolate was a new variant of IBV.     

HSV-2gD融合gB CTL表位重组蛋白的原核表达及免疫原性评价

为研制具有较强细胞免疫作用的单纯疱疹病毒Ⅱ型(HSV-2)疫苗,将HSV-2糖蛋白D(gD)序列与糖蛋白B(gB)上两种CTL表位序列连接,人工合成重组基因gD-gBCTL,通过PCR扩增,将其克隆后连接至原核表达栽体pET-22b(+),构建重组基因表达质粒pET-22b(+)-gD-gBCTL,转化E.coli B...     

中国家驴生长激素基因内含子2的遗传多样性分析

为了从分子水平揭示家驴的遗传多样性,本研究以中国7个家驴品种(临县驴、关中驴、新疆驴、广灵驴、淮北驴、德州驴、晋南驴)174个个体为试验动物,利用PCR-SSCP技术研究生长激素(GH)基因第2内含子的遗传多样性并进行序列分析.结果显示:第2内含子表现多态性,174个个体检测到3个单倍型,单倍型比例为1.7%.单倍型多样度以临县驴、淮北驴较高,分别为0.678和0.542.广灵驴与关中驴的单倍型多样度(Haplotype diversity,H)比较接近,分别为0.409和0.462.其次为德州驴和晋南驴,分别为0.355和0.304,新疆驴最低为0.077.对该片段的纯合型分别测序发现,B单倍型在第735位碱基G→C.A单倍型在869位碱基G→T.上述结果首次证实驴GH基因内含子2存在多态性.     

副猪嗜血杆菌广东流行株的分离鉴定与基因分析

本研究从广东省各个地区送检病料中成功分离鉴定了4株副猪嗜血杆菌,并且针对副猪嗜血杆菌16S rRNA基因特异性进行PCR检测和基因测序同源性分析,通过GenBank联机比对分析,所分离的菌株与国内外菌株16S rRNA序列同源性在98.2%以上,分离菌株之间同源性在99.6%~100%之间,证明了所暴发的菌株是副猪嗜血杆菌。     

不同植物蛋白源日粮对山羊血液氮素代谢的影响

本试验旨在研究不同植物蛋白源日粮对山羊血液氮素代谢的影响。选择3头体况良好安装有颈动脉、门静脉和肠系膜静脉插管的徐淮白山羊,采用3×3拉丁方试验设计,以3种植物蛋白饲料-豆粕(A)、棉粕(B)和玉米干酒糟及其可溶物(C)作为蛋白源。结果表明:不同蛋白源日粮显著影响动脉和门静脉中尿素氮浓度(P<0.05);显著影响肠系膜静脉中总15N、蛋白态15N和氨基酸态15N丰度(P<0.05),且血液中15N丰度均为C组>A组>B组;各处理组间门静脉排流组织(PDV)和肠系膜排流组织(MDV)中总15N和蛋白态15N净流量差异均不显著(P>0.05),但不同蛋白源日粮显著影响PDV和MDV组织中游离氨基酸态15N净流量,且均以C组最高;各处理组中总游离氨基酸(TFAA)和总肽结合氨基酸(TPAA)浓度均存在显著差异(P<0.05)。综合上述,徐淮白山羊以玉米干酒糟及其可溶物作为植物蛋白源比豆粕和棉粕效果更好。     

Expression kinetics of chicken β2-microglobulin and Class I MHC in vitro and in vivo during Marek’s disease viral infections

Marek’s disease virus (MDV) is a highly cell-associated herpesvirus that causes a disease in chickens characterized by tumor formation and immunosuppression. The changes of major histocompatibility complex (MHC) expression in different MDV-infected cells are not completely understood. In this study, we investigated the expression of the Class I MHC and β2-microglobulin (β2m) genes in response to MDV infection at different time points by real-time PCR. In both in vitro and in vivo, the expression levels of Class I MHC and β2m genes were upregulated during early MDV infections in comparison to control cells; We also found that the expression of Class I MHC gene was downregulated in BudR (5-bromo-2′-deoxyuridine)-treated MSB1 cells at 48 h and MDV-infected chicken embryo fibroblast cells (CEF) at 120 and 168 h post infection (hpi); Furthermore, compared to control groups, Class I MHC and β2m expression levels were downregulated in peripheral blood lymphocytes (PBLC) from MDV-infected chickens at 14 and 28 days post infection (dpi); Interestingly, both Class I MHC and β2m gene expression levels increased again in PBLC from MDV RB1B-infected chickens at 35 dpi, in which MDV was in the latent or transformed infection stages. In addition, Class I MHC expression was clearly decreased in MDV-infected CEF at 120 hpi although β2m expression was significantly increased. These changes in Class I MHC and β2m gene expression might provide more insights into host-virus interaction.