神经型犬瘟热的诊治

20 0 0年 2月 2 1日 ,凭祥出入境检验检疫局第二生活区所饲养的 2只杂狼犬先后出现下痢、口吐白沫、双相热型 ,后出现以神经症状为主要特征的疾病 ,经临床检查、病理解剖、细菌学检查、药物治疗分析 ,确诊为神经型犬瘟热。1　发病情况2月 2 1日 ,凭祥出入境检验检疫局第二生活区所饲养的 2条 3月龄左右、黑色、一公一母、体重约 8千克、长势良好的杂狼犬中的母犬下痢 ,口吐少量白沫 ,体温为 39 5℃ ,食欲不振。 2月 2 3日 ,体温降为 37 8℃ ,吃少量食物 ,多饮水 ,2月 2 5日 ,体温又升高到 39 5℃ ,精神沉郁 ,食欲废绝 ,站立不稳 ,步态踉跄 ,…     

神经型犬瘟热的治疗

1病毒与发病机理 1．1病毒犬瘟热病毒是副粘病毒科麻疹病毒属成员。犬瘟热病毒呈多形性,单股RNA病毒,核衣壳呈螺旋对称,有囊膜。其抵抗力差,对热、干燥、紫外线和有机溶剂敏感．易被日光、酒精、甲醛、煤酚皂等杀灭。pH4．5以下和9．0以上的强酸、强碱环境也可使其迅速灭活．其在低温冻结条件下可保存几个月,冷冻干燥条件下可保存数天。     

神经型犬瘟热的治疗与剖检变化

对一例神经型犬瘟热病的中药治疗试验,并对病死犬进行了剖检,对肺病变部位进行了细菌分离培养,分别对脑组织和腰部脊髓进行石蜡切片。结果表明,在犬的肺组织中分离出葡萄球菌,小脑颗粒细胞层出现坏死灶,大脑皮层血管充血,但在脑组织和腰部脊髓中未发现细胞内包涵体。     

一例神经型犬瘟热的诊治报告

犬瘟热是由犬瘟热病毒引起的一种高度接触性传染病,传染性强,死亡率高,尤其是2周岁以下的狗容易被传染。1病例介绍2007年3月28日,广州市黄小姐带来一条近6月龄、体重20kg左右的金毛犬。主诉该犬从前些日参加完犬展,回来后便食欲不振、不愿活动并有大量脓性鼻涕,眼周分泌物较多,     

肺型犬瘟热的诊治

1发病情况2008年1月,承德县上板城镇养犬户王某的犬群发病3天后,到我处就诊。经询问了解到该养犬户共饲养犬153只,发病23只,其中3月龄以下仔犬16只,死亡9只,发病比较急,仔犬死亡率高。发病率为15%,死亡占发病数的39.1%。     

全身型及神经型犬瘟热的发病机理和免疫病理特性

犬瘟热是由麻疹病毒引起的犬易感的一种全球性传染性疾病,与麻疹和牛瘟病毒关系密切。该病毒的自然宿主主要是食肉动物。犬瘟热病毒（CDV）是有囊膜的负链RNA病毒,可以感染不同类型的细胞,包括上皮细胞、骨髓细胞、神经内分泌细胞和各种器官与组织中的造血干细胞。感染犬瘟热病毒的犬出现特征性的系统型和/或神经型的临床表现,病毒持续存在于特定的器官,包括中枢神经系统（CNS）和淋巴组织。主要临床表现包括：呼吸道和胃肠道症状、免疫抑制和脱髓鞘脑膜脑炎。免疫功能受损与淋巴器官耗竭有关,包括一种与败血症相关的淋巴细胞的减少,尤其是早期感染阶段淋巴组织细胞凋亡引起的CD4^＋T细胞的减少。病毒在外周血中被清除后,尽管淋巴器官种群恢复,但可能由于抗原递呈减少及淋巴细胞成熟过程的改变导致持续的免疫抑制。早期阶段的脱髓鞘脑膜脑炎是直接由病毒介导的病变及CD8^＋细胞毒性T细胞渗透所形成的后遗症,伴随相关前炎症细胞因子（如IL-6、IL-8、TNF-α、IL-12）的上调和免疫调节细胞因子（如IL-10和TGF-β）的缺乏。慢性阶段髓磷脂的减少是由CD4^＋介导的迟发型超敏反应和细胞毒性CD8^＋T细胞引起的。另外,在更进一步的病变中,干扰素-γ和IL-1可能上调。此外,基质金属蛋白酶及其抑制剂平衡的改变,似乎在脱髓鞘脑膜脑炎的发生过程中发挥关键作用。总之,脱髓鞘脑膜脑炎代表了由最初的直接病毒介导的过程和免疫介导的蚀斑进展组成的双相疾病过程。免疫抑制是由于感染早期病毒介导的淋巴细胞裂解,以及一些还不清楚的影响抗原递呈和淋巴细胞成熟的机制所造成的。     

表达犬瘟热病毒H基因的重组犬2型腺病毒的构建与鉴定

将犬瘟热病毒 ( canine distemper virus,CDV ) H基因表达盒克隆入转移质粒 p VAXΔE3,构建含 CDV H基因表达盒的转移质粒 p VAXΔ E3L PH,用 Nru 和 Sal 分别酶切转移质粒 p VAXΔ E3L PH和犬 2型腺病毒全基因组质粒p Poly2 - CAV- 2 ,将 CDV H基因表达盒定向克隆入 p Poly2 - CAV- 2质粒中 ,构建 E3区部分缺失的包含 CDV H基因表达盒的犬 2型腺病毒重组质粒 p CAV- 2 / CDVL PH。 Asc 和 Cla 对 p CAV- 2 / CDVL PH进行双酶切 ,释放 CAV- 2 /CDVL PH重组基因组 ,利用脂质体将 CAV- 2 / CDVL PH重组基因组与去除 Sal 和 Nru 片段的 CAV- 2基因组两端片段共转染 DK细胞 ,盲传和重复转染 3次 ,4 d后出现典型 CAV- 2病变 ,获得重组病毒 CAV- 2 / CDVL PH。用 CDV H基因特异性引物经 RT- PCR扩增重组病毒 DK细胞培养物 ,能够扩增出相应的核酸片段 ,表明 CAV- 2 / CDVL PH在DK细胞繁殖的过程中能够转录 CDVL P H的 m RNA,重组病毒免疫犬 ,可以诱导犬产生特异的抗 CAV- 2 HI抗体和抗 CDV中和抗体     

犬瘟热病毒和犬腺病毒2型双重PCR方法的建立及应用

根据犬瘟热病毒(canine distemper virus,CDV)和犬腺病毒2型(Canineadenovirus type2,CAV-2)GeneBank登陆的基因序列各设计一对引物,经试验条件优化,建立了检测CAV-2的PCR方法和CDV的RT-PCR方法,CAV-2可扩增1108bp片段、CDV可扩增560bp的目的片段,特异性试验表明建立的方法只能特异扩增CAV-2和CDV,不能扩增犬细小病毒、犬冠状病毒、犬副流感病毒、犬钩端螺旋体和犬黄胆出血群、狂犬病病毒。敏感性试验表明,所建立的双重PCR方法可以扩增4.63ng总核酸量。在上述试验基础上继续优化条件建立了能同时检测CAV-2和CDV两种病毒的双重PCR检测方法,并用该方法检测来自辽宁、吉林等15家动物医院134份鼻液和眼眵样品,与商品化试纸条检测结果相比,本方法更加敏感和方便。研究结果表明,本实验建立的方法敏感、特异,适用于动物犬瘟热病毒和犬腺病毒2型的快速检测和鉴别诊断。     

一例肺型犬瘟热的诊治

犬瘟热是由犬瘟热病毒引起的犬科（犬、狐、貂）动物的一种急性、烈性、高度接触性的传染病。早期呈双相热型,症状类似感冒,随后以支气管炎、卡他性肺炎为特征,严重的有胃肠炎和神经症状。     

乳酸和柠檬酸在酸型含乳饮料中的应用

本文通过测量柠檬酸和乳酸低浓度范围下的水溶液的滴定酸度°T和pH,以及在酸牛乳饮品中的应用,绘制出柠檬酸和乳酸在水溶液和酸牛奶饮品中的标准曲线,为生产时计算柠檬酸或乳酸的添加量提供了数据基础。     

Canine distemper virus infection of canine footpad epidermis

Infection of the footpad epidermis can occur in natural canine distemper virus (CDV) infection of dogs. Footpads from 19 dogs experimentally inoculated with virulent distemper strain A75/17 and from two nonexposed dogs were examined histopathologically and assessed for the presence of viral antigen and nucleoprotein mRNA, as well as number of inflammatory and apoptotic cells. Dogs were divided into four groups based on inoculation status and postmortem examination: inoculated dogs with severe distemper (group 1, n = 7); inoculated dogs with mild distemper (group 2, n = 4); inoculated dogs without distemper (group 3, n = 8); and noninoculated dogs (group 4, n = 2). Footpads from dogs of all groups had a comparably thick epidermis. Eosinophilic viral inclusions and syncytial cells were present in footpad epidermis of one dog of group 1. Footpads of group 1 dogs contained viral antigen and mRNA in the epidermis with strongest staining in a subcorneal location. Additionally, in these dogs footpad dermal structures including eccrine glands and vascular walls were positive for virus particles. No CDV antigen or mRNA was present in the footpad epidermis and dermis of any other dog. Group 1 dogs had more CD3-positive cells and apoptotic cells within the basal layer of the epidermis when compared to the other groups. These findings demonstrate that in experimental infection CDV antigen and mRNA were colocalized in all layers of the infected canine footpad epidermis. The scarcity of overt pathological reactions with absence of keratinocyte degeneration indicates a noncytocidal persisting infection of footpad keratinocytes by CDV.     

Up-regulation of cytokeratin expression in canine distemper virus-infected canine footpad epidermis

Cytokeratin expression was assessed in footpad epidermis from dogs using immunohistochemistry. Four groups of dogs were studied: dogs with experimentally induced distemper and with canine distemper virus (CDV) in footpad epidermis (group 1, n = 7); dogs with experimentally induced distemper and without CDV in footpad epidermis (group 2, n = 4); inoculated dogs without distemper and without CDV in the footpad epidermis (group 3, n = 8), and noninoculated dogs without distemper (group 4, n = 2). No increase in thickness of the footpad epidermis was present in any of these groups. Sections of metacarpal or metatarsal pads were stained for cytokeratin (CK)14 (proliferation-associated), CK10 (correlated with early differentiation), and for involucrin (associated with terminal differentiation). CK14 was present in basal keratinocytes of all groups, but staining intensity decreased towards the corneal layer in groups 2-4, but not in group 1. CK10 was present in the spinous and granular layer of all groups, but staining of the granular layer was much stronger in group 1. Involucrin was present in the granular layer of footpads of group 1 and only in the upper part of this layer in groups 2-4. The results demonstrate increased staining intensity and/or wider distribution within the footpad epidermis in group 1 dogs when compared to the other groups. This was interpreted as up-regulation in expression of these proteins. These findings suggest that presence of CDV antigen and mRNA in footpad epidermis was associated with an increase in expression of CK14, CK10 and involucrin. The potential role of this up-regulation in cytokeratin expression in the development of CDV-induced digital hyperkeratosis remains speculative at the moment and requires further studies.     

同时检测犬瘟热病毒和犬细小病毒双重PCR方法的建立

为建立可以同时检测犬瘟热病毒(CDV)和犬细小病毒(CPV)的双重PCR方法,本研究根据GenBank登录的CDV N蛋白序列和CPV NS基因保守序列,设计合成2对特异性引物。通过优化反应条件,对CDV阳性病毒株反转录后的cDNA模板和CPV的DNA模板进行双重PCR扩增,同时得到2条与试验设计相符的669 bp(CDV)和392 bp(CPV)特异性条带,建立了同时检测CDV和CPV的双重PCR方法。实验结果表明:在同一PCR反应体系中可以同时检测这2种病毒,而对犬腺病毒Ⅰ型、犬腺病毒Ⅱ型、狂犬病毒检测均为阴性;CDV和CPV的最低检出限分别为101.8TCID50和101.4TCID50。采用该方法对在黑龙江省不同地区所采集的30份犬病料样品进行检测,CDV阳性率为30%;CPV阳性率为23.33%,表明建立的PCR方法可以用于临床诊断。     

A canine distemper virus seroprevalence study of dogs on three islands in the Torres Strait region,Australia

Canine distemper virus (CDV) can cause mortality in domestic dogs, which is easily prevented by the consistent application of vaccination protocols. The aim of this study was to determine if the dog populations of three strategically located islands in the Torres Strait of Australia, adjacent to Papua New Guinea, are infected by CDV. Eighty-four serum samples were collected from 70 dogs resident on Saibai, Dauan and Boigu Islands during 2017–2018. Sera were tested for CDV antibodies by a virus neutralization test (VNT). Overall, 7 (8.3%) sera from 6 (8.6%) dogs resident on all three islands were test positive. VNT titres ranged from 20 to >1280. Male adult dogs were more commonly seropositive than female and juvenile dogs. Considering the origin and age of test positive dogs, and veterinary visits to these islands, it was concluded that there is evidence of exposure to a field strain of CDV – rather than previous vaccination – in 4 of the 70 dogs (5.7%) tested in this study. Given the strategic location of these islands in a zone of high biosecurity risk, ongoing surveillance of pathogens such as CDV could inform on potential disease spread pathways in this region. In addition, the presence of high serological titres in the apparent absence of clinical disease requires further investigation.     

犬瘟热病毒融合蛋白、血凝蛋白、基质蛋白和核衣壳蛋白基因DNA联合免疫的研究

为研究犬瘟热病毒(CDV)融合蛋白(F)、血凝蛋白(H)、基质膜蛋白(M)和核衣壳蛋白(N)基因核酸联合免疫的效力,本研究分别构建了表达经哺乳动物密码子优化的CDV F、H、M和N蛋白基因的真核重组表达质粒p CAGG-CDVF、p CAGG-CDVH、p CAGG-CDVM和p CAGG-CDVN;将其分别转染BHK-21细胞后通过间接免疫荧光试验表明,目的蛋白均获得正确表达。此外,将等量混合的重组质粒p CAGG-CDVF、p CAGG-CDVH、p CAGG-CDVM(3组份DNA疫苗)或重组质粒p CAGG-CDVF、p CAGG-CDVH、p CAGG-CDVM、p CAGG-CDVN(4组份DNA疫苗),分别以500μg/只经肌肉注射途径免疫A组(6只)或B组(6只)比格犬,间隔4周以相同剂量、途径加强免疫一次,并于初次免疫前、后不同时间检测血清CDV中和抗体。中和试验结果显示,A组和B组免疫犬,二免4周时,CDV中和抗体滴度平均值达到峰值,分别为6 log2和5.64 log2;在初免54周时,CDV中和抗体滴度均仍然维持5 log2。因此,3组份DNA疫苗为具有良好应用前景的犬瘟热候选疫苗。     

贵州犬瘟热病毒的分离鉴定

对流行病学调查、临床症状检查和ELISA检测为犬瘟热阳性的自然发病犬,取肠内容物为病料,采用同步培养方法接种于犬肾细胞系(MDCK)进行病毒的分离,并对分离株进行了形态学特征、血凝特性、动物感染及RT-PCR鉴定。结果表明:病料接种MDCK细胞产生明显的细胞病变(CPE),电镜负染观察接毒细胞培养物见有典型的犬瘟热病毒粒子。分离株不凝集鸡及人“O”型红细胞,接种犬出现明显的临床症状和病理变化。用RT-PCR技术检测病毒细胞培养液,扩增出的片段长为760 bp,与预期设计的长度相同,由此确证分离株为犬瘟热病毒,命名为CDV-GZ2株。     

RT-PCR检测贵州犬瘟热病毒

根据犬瘟热病毒H基因核苷酸序列 ,设计合成一对引物对贵州临床诊断为犬瘟热 (CD)病死犬的心、肝、脾、肾、粪便进行RT PCR检测。结果表明 :从心、脾、肾病料上清液中可扩增出 760bp的特异性带 ,与预期扩增片段长度相同 ;粪便和肝脏上清液RT PCR结果为阴性 ,但粪便上清液接种Vero细胞后连续传代 3代 ,每代细胞培养液RT PCR结果均为阳性 ;在检测的 2 2条病死犬中 ,有 1 9条病死犬检测到犬瘟热病毒H基因的特异性核酸片段 ,阳性率为 86 4% (1 9/ 2 2 )。     

犬瘟热病毒N蛋白的B细胞抗原表位预测

将1段犬瘟热病毒N蛋白氨基酸序列（GenBank编号为：AEV77096．1）与GenBank登录的其他氨基酸序列进行比对,分析其同源性;通过DNAStar生物信息学分析软件中的Protean模块及The PredictProteinserver在线蛋白分析工具预测犬瘟热病毒N蛋白的理化性质、二级结构、亲水性、表面可及性、柔韧性、抗原指数、跨膜螺旋、蛋白相互作用位点、蛋白功能位点等特性,并预测其B细胞优势抗原表位。结果显示,犬瘟热病毒N蛋白具有规则的二级结构、亲水性、柔韧性片段多,多处于表面可及性大,抗原指数高,蛋白质相互作用位点区域。潜在的B细胞优势抗原表位为12～18、61～66、243～246、410～415、421～429、434～447、452～456、480～487氨基酸序列。结果表明,本试验预测了犬瘟热病毒N蛋白的B细胞优势抗原表位,为进一步设计犬瘟热病毒的诊断抗原多肽、免疫用抗原多肽和研发血清学检测试剂盒奠定了理论基础。     

Atypical necrotizing encephalitis associated with systemic canine distemper virus infection in pups

This report describes the naturally occurring atypical neuropathological manifestation of systemic canine distemper virus (CDV) infection in two 16-day-old Pit Bull pups. CDV-induced changes affected the gray and white matter of the forebrain while sparing the hindbrain. Histologically, there was necrosis with destruction of the nervous parenchyma due to an influx of inflammatory and reactive cells associated with eosinophilic intranuclear inclusion bodies within glial cells. Positive immunoreactivity against CDV antigens was predominantly observed within astrocytes and neurons. RT-PCR was used to amplify CDV-specific amplicons from brain fragments. These findings suggest the participation of CDV in the etiopathogenesis of these lesions.