犬的种类知多少

家犬虽然在动物的分类学上只是一个种(Canis familiaris),可是由于人类的长期饲养和人为选择筛选,世界上已有超过300种各式各样犬的品种,它们无论是外型还是性格到功能都有区别,其差异之大,远远超过了犬科中的其它物种。近代分类学鼻祖林奈,曾于18世纪罗列了当时存在的各种犬类,但没有进行详细分类。事实上,现代犬的形态与血统都很复杂,要想正确地对众多犬种进行分类是比较困难的。目前,犬的分类方法很多,主要有:根据犬的形态特征分类,可分为:灵(犭是),猎鹬犬,狐狸犬,(犭更),马尔济斯犬,(犭是)和牧羊犬七大类。     

犬瘟热和犬冠状病毒联合RT-PCR检测方法的应用

塔里木农垦大学乔军、解放军大学夏咸柱、东北农业大学何宠彬等对此课题进行了研究。他们利用犬瘟热(CDV)和犬冠状病毒(CCV)牧异性引物对同一样品中CDV和CCV的RNA模板进行联合RT—PCR扩增,并优化其扩增条件,得到两条大小与试验设计完全相符的特异性扩增带,且不扩增犬细小病毒、犬腺病毒、犬副流感病毒、轮状病毒的核酸。其敏感性试验表明：该联合PCR能检测出10^-4倍稀释的CDV模板(10^6.6TCID50／0．1mL)。对7份临床发病犬病科检测,其阳性检出率可高于电镜负染检查。这表明此法有高度敏感、特异、准确、快速等特点,适用于当前民用和军用兽医临床对CDV、CCV的检测和对犬的其他疾病的鉴别诊断。     

明星公益犬

旺财最会表演的公益犬。它接受过专业的服从性及城市搜救的训练。不但外型飘逸,还具备算术、搜索、衔飞盘等许多技能。在活动中主要担任展示和表演的工作。特别是探访盲童的时候,孩子们看不到其他表演。于是旺财就做算术表演,用叫声来给出答案。任何有旺财的地方都会有孩子们的掌声和欢呼声。品种:苏格兰牧羊犬性别:雄     

犬布鲁氏菌病

目前,犬布鲁氏菌病在全球多个国家和地区都有发生,而且发病数量逐年上升,由犬布鲁氏菌病感染人的病例报道也日益增多。因此,犬布鲁氏菌病的控制和根除对人类健康和公共卫生安全具有重要的意义。据报道,我国多个省份存在犬布鲁氏菌病,而且感染和发病率有上升的趋势。由于我国养犬数量巨大,犬与人类接触密切,病犬作为人类布鲁氏菌病的传染源不容忽视。犬布鲁氏菌病的研究起步较晚,流行病学资料欠完善,公共卫生学意义有待阐明,诊断、免疫预防等诸多问题还没完全解决,加强犬布鲁氏菌病的研究和防控应引起足够的重视。本文就犬布鲁氏菌病的病原学、流行病学、病理学、临床症状、诊断、治疗、预防及公共卫生安全等分别做一阐述。     

狗年话犬

不知何故,在中国传统文化中,狗和狼及其同类总是被冠以恶名;而在西方,狗却被视为人类的忠实朋友,甚至是家庭成员;如果有人胆敢虐待狗,那肯定会招致麻烦。在中西文化中对待狗所表现出如此之截然不同态度,这其中究竟隐含着什么样的深层次原因,在此暂且不去探究。单从进化角度看,犬科动物确实是动物界最成功者之一。     

广州地区犬蝠的食性

2004年5月-2006年4月采用拾遗法、粪便内容物分析法及实地观察对广州地区常见的食果蝙蝠-犬蝠(Cynopterus sphinx)进行了食性研究。对26份食物残留物和粪便样品的分析结果表明:犬蝠的食物包含13科21种的植物果实,3科3种的植物叶片,如:蒲桃(Syzygium jambos)、蒲葵(Livistona subglobosa)及龙眼(Dimocarous longan)的果实。其食性随果实的成熟季节而出现明显的季节性变化,夏秋两季大量食用各种水果,而在食物欠缺的春冬两季则主要食用棕榈科蒲葵的种子。广州地区犬蝠的繁殖期在每年的5-10月。     

Beagle犬的基础数据

目的检测不同性别年龄段Beagle犬的血液学和血生化指标,解剖称量分析8～12月龄Beagle犬脏器重量、系数等基础数据,为实验用Beagle犬的应用与研究提供参考数据。方法采用HITACHI-7020自动生化分析仪和SWELAB—AC920EO血球自动分析仪,检测了3000多只次不同性别和年龄的健康Beagle犬的血液学和血生化数据;解剖128头Beagle犬,称量及计算正常Beagle犬各内脏器官重量及系数。结果和结论获得正常Beagle犬的血液学RBC、HCT、MCV、RDW、HGB、MCH、MCHC、PLT、WBC、LYM、MID、GRA等指标正常值及标准差,血生化ALT、AST、ALP、TP、ALB、BUN、CREA、GLU、TCHO、TBILI、TG等指标正常值及标准差;获得Beagle犬心脏、肝脏、脾脏、肺脏、左右肾、脑、肾上腺、胸腺、甲状腺、睾丸、前列腺、子宫、卵巢等内脏器官的重量和系数正常值及标准差。     

犬肿瘤免疫疗法的研究进展

目前,犬肿瘤疾病已成为临床常见病。手术疗法、放射疗法及化学疗法作为传统治疗手段虽然在一定程度上能够改善病犬的生存及预后,但仍不能彻底改变病犬的生存质量。因此,新的肿瘤治疗方式的引入迫在眉睫。肿瘤免疫疗法的诞生为犬类肿瘤的预防和治疗提供了契机。该文综述了犬肿瘤免疫疗法的研究进展,包括免疫检查点如程序性死亡受体1(programmed cell death 1,PD-1)/程序性死亡受体配体1(programmed cell death ligand 1,PD-L1)及细胞毒性T淋巴细胞抗原-4(cytotoxic T lymphocyte antigen-4,CTLA-4)。同时,该文评述了过继细胞疗法(adoptive cell therapy,ACT)在犬肿瘤治疗中的前景,为未来犬肿瘤治疗的研究方向提供了理论基础。     

犬腺病毒、犬细小病毒联合PCR方法的建立与应用

根据GenBank报道的犬腺病毒(CAV)和犬细小病毒(CPV)序列,设计两对联合PCR引物,其中一对为CAV-1和CAV-2通用引物,另一对为CPV引物。在建立单项PCR基础上,通过优化Mg^2 离子浓度和循环参数等反应条件建立联合PCR,确定联合PCR条件为：96℃180s,96℃230s,56℃30s,72℃280s,30个循环。联合PCR结果显示：CAV—l扩增片段大小为497bp,CAV-2为l019hp,CPV为719hp;细胞和其它相关病毒对照均无扩增带。上述PCR产物经用限制性内切酶酶切和克隆测序,结果均与相应病毒的应有条带和序列相同。敏感性比较试验结果表明。联合PCR比用细胞培养分离病毒敏感。将联合PCR应用于15份CAV和CPV细胞培养物,5份CAV-1、1份CAV-2和3份CPV人工感染犬病料以及30份临床病料检测,并与电镜负染、HA／HI及病毒分离等方法的结果进行比较,结果显示,联合PCR的检出率和病毒分离结果一致,高于电镜负染和HA／HI试验。以上结果说明：CAV-1／12AV-2和CPV联合PCR不仅具有很好的特异性和敏感性,而且可以在短时间内(2．5h～3h)同时鉴定出上述三种病毒。因此具有良好的实验室诊断和临床应用价值。     

公益犬在行动

除了军犬、警犬,中国还没有真正意义上的工作犬。为了传播狗能够服务于人类的理念,使人们加深对犬的全方位了解,建立人犬和谐关系,我所在的“中国犬与社会公益组织(Canine Society of China,简称 CSCN)”推出了公益犬活动。其实,国外并没有“公益犬”这样一个概念,这是一个我们独创的词。所谓公益犬,就是经过严格的健康检查和行为测评后可以从事公益活动的狗,相对与国外的工作犬来说,公益犬最大的不同就在于,无论是狗还是它们的主人,来参加我们的活动都不会得到任何形式的报酬。来参加我们活动的公益犬大都是家庭宠物犬,我们不介意它们的品种、性别和年龄,只要通过体检和行为测评合格的狗,我们都会带它们参加一些社会活动,去帮助我们能够帮助的人。     

Serologic survey for canine distemper and infectious canine hepatitis in wolves in Alaska

Sera from 57 wolves (Canis lupus) in three areas of Alaska were evaluated for evidence of previous exposure to infectious canine hepatitis virus (ICHV) and canine distemper virus (CDV). Fifty-four sera (94.7%) were positive for ICHV exposure and four (7%) were positive for CDV exposure. All four CDV-reacting wolves also had titres to ICHV. The relatively common occurrence of ICHV exposure may be due to the greater resistance of ICHV to chemical and physical agents and its transmissibility via the urine of infected animals. The ICHV titres observed could indicate enzootic pathogenic ICHV, or exposure to the mildly pathogenic vaccine strain of CAV-1 through contact with the urine of domestic dogs. If CAV-1 is the original source of exposure, the titres could represent an ICHV-protected wolf population.     

犬传染性肝炎病毒在体外细胞质内的发生

通过对犬传染性肝炎病毒（ＩＣＨＶ）在犬肾传代细胞内形态发生及其抗原定位的电镜和免疫胶体金电镜研究,发现ＩＣＨＶ除了在宿主细胞核内发生外,还有一条细胞质内的发生途径。在细胞质内病毒核壳体的装配是以均质致密包涵体和副晶格包涵体为“基地”,这与人们熟知的细胞核内形态发生方式相似。免疫胶体金标记显示,细胞质包涵体中含有大量的ＩＣＨＶ抗原成分,显核壳体在细胞质内装配病毒的结构蛋白来源。此外,在感染的细胞质内还观察到与核内相同的病毒核心样结构。     

重组虎源H5N1流感病毒HA基因犬2型腺病毒的构建与实验免疫研究

H5N1流感病毒可以对虎和猫产生致死性感染,为研制可用于预防猫科动物流感的新型疫苗,构建了重组虎源H5N1流感病毒HA基因的犬2型腺病毒。将A/Tiger/Harbin/01/2003(H5N1)的HA基因克隆入pVAX1载体中,然后将含有HA基因的表达盒(CMV HA PolyA)克隆入pVAXΔE3的SSPⅠ酶切缺失处,获得含有HA表达盒的穿梭载体pΔEHA。用SalⅠ NruⅠ分别对pΔEHA和pPoly-2-CAV2进行双酶切,将含有HA表达盒的SalⅠ NruⅠ片段克隆入pPoly2-CAV2,获得了在E3区缺失处插入HA表达盒的重组质粒pCAV-2/HA。释放CAV-2/HA重组基因组转染MDCK细胞,获得了重组活病毒CAV2/HA,经Western blot分析表明重组表达产物可被流感病毒HA单克隆抗体3A13所识别。使用该重组病毒免疫猫可以产生效价为1∶8~1∶16的抗H5亚型流感病毒血凝抑制抗体。     

犬瘟热病毒（CDV）ELISA检测方法的建立与应用

目的建立犬CDV抗体ELISA检测方法。方法培养vero细胞,接种CDV病毒,制备vero正常抗原和CDV特异抗原,滴定酶结合物和抗原最佳工作浓度,并进行精密性、敏感性、稳定性、特异性实验。结果正常、特异抗原和酶结合物最佳工作浓度分别为1∶32 000、10μg/mL和1∶8 000;正常、特异抗原批内变异系数分别为9.1%和5.8%,批间平均变异系数分别为8.8%和6.6%;检测灵敏度为1∶2 560;与犬细小病毒（CPV）、犬肝炎病毒（ICHV）均无交叉反应。稳定性试验相对偏差小于25%。结论建立的ELISA方法重复性、稳定性好,特异性、敏感性强。可用于犬CDV抗体的检测。     

犬传染性肝炎病毒Hexon蛋白Loop1、Loop2基因的克隆与表达

犬传染性肝炎病毒（ICHV）主要的中和抗原表位位于六邻体蛋白Loop1、Loop2上。本次研究参考Genebank发表的基因序列设计引物,提取ICHV基因组DNA,,分别PCR扩增六邻体蛋白（Hexon）的Loop1、Loop2基因片段,用T4酶连接在一起,克隆入原核表达载体pET28a中,测序显示本室保存病毒分离株Loop1与CLL株、RI261株和Toronto A26/61株核苷酸序列同源性分别为100%、100%和83.8%;Loop2与CLL株、RI261株和Toronto A26/61株核苷酸序列同源性分别为88.1%、88.1%和99.3%,推导的氨基酸序列同源性分别为93.6%、93.6%和98.6%。转化BL21工程菌,实现了重组Loop蛋白在大肠杆菌中的高效表达,其表达的重组蛋白以包涵体形式存在,分子量约为36kDa,并且利用镍柱纯化重组蛋白,纯度达95%以上。本实验为建立新的犬传染性肝炎病毒基因工程产品奠定了良好的基础。     

四价流感病毒裂解疫苗B型血凝素含量的检测方法

目的建立能准确测定四价流感病毒裂解疫苗中B型血凝素含量(单向免疫扩散法,SRD)的检测方法。方法采用双价抗原参考品SRD法对四价流感病毒裂解疫苗中两种B型血凝素含量进行测定。将B1与B2抗原参考品按质量浓度1∶1混合制备为双价抗原参考品,双价抗原和待检样品与10%裂解剂按9∶1比例裂解30 min,分别加入到含有抗血清参考品的1.5%琼脂糖凝胶板上,每孔10μL,置20~25℃放置18~24 h,经干燥、染色、脱色,测量结果。验证双价抗原SRD法的重复性和准确性。结果双价抗原SRD法测定的血凝素含量平均值比单价抗原SRD法更接近理论配制值,故双价抗原SRD法比单价抗原SRD法能更能准确检测QIV中两种B型血凝素含量,经验证双价抗原SRD法的重复性及准确性良好。结论双价抗原SRD法提高了四价流感病毒裂解疫苗B型血凝素含量检测的准确性,为精确测定四价流感病毒裂解疫苗中B型血凝素含量提供了有效的方法和数据支持。     

In vitro antibody response to influenza virus. II. Specificity of helper T cell recognizing hemagglutinin

Intraperitoneal immunization of mice with liver influenza virus was shown to induce helper T (TH) cells with specificity for the hemagglutinin (HA). The interaction of virus-primed TH cells with purified HA was studied independently of B cell reactivity to the same antigen by using the generation of nonspecific help as an index of activation of HA-specific TH cells. TH cells from mice primed with any of the H3 viruses A/Aichi/68 X A/Bel/42 (H3N1), A/Memphis/102/72 X A/Bel/42 (H3N1) or A/Port Chalmers/73 (H3N2) were strongly cross-reactive towards HA of other strains within the H3 subtype. In addition, several examples of cross-reactivity towards HA of a different subtype were observed, usually of a lower magnitude. TH cells from mice primed to any of the H3 viruses above or to A/Bel/42 (H1N1) virus cross-reacted with the HA of A/Japan/305/57 (H2); furthermore, priming with A/Bel/42 or with A/Jap/305/57 X A/Bel/42 (h2N1) virus yielded TH cells that cross-reacted with certain of the H3 HA preparations. The cross-reactivity observed between subtypes was not due to the common chicken host carbohydrate component of HA, since no response to the purified type A HA preparations was obtained with T cells from mice primed with egg-grown influenza B/Hong-Kong/8/73 virus. The results indicate that HA of different subtypes may share cross-reactive antigenic determinants recognized by TH cells. Within a subtype, HA are highly cross-reactive with respect to tH cell recognition.     

Hepatitis A antigen isolated from liver and stool: immunologic comparison of antisera prepared in guinea pigs.

Morphologically similar hepatitis A antigen particles (HA Ag)3 have been detected in the stools of patients with type A hepatitis and in the livers of marmosets experimentally infected with hepatitis A virus. To investigate the humoral antibody responses to these antigens and to compare the immunologic properties of HA Ag from these two sources, we immunized guinea pigs with either marmoset liver-derived HA Ag or with human stool-derived HA Ag in complete Freund's adjuvant and measured their antibody responses by immune electron microscopy (IEM) and immune adherence hemagglutination (IAHA). Antibodies reacting with both hepatitis A antigens were elicited in both groups. As determined by IEM, no distinction was seen between the reaction of guinea pig antiserum to each HA Ag tested under code when reacted against either liver-derived or stool-derived HA Ag. Antibodies elicited to marmoset liver-derived HA Ag and human stool-derived HA Ag had similar end point dilution titers by IAHA when tested against either "light" density (1.34 g/cm3) or "heavy" density (1.40 g/cm3) stool-derived HA Ag or liver-derived HA Ag. Low levels of antibody to normal liver or stool control antigens were observed transiently but did not obscure the specific response to HA Ag. These data suggest that morphologically similar HA Ag particles from different sources and with different densities are immunologically similar and may be identical. In contrast to the heterogeneity of surface antigens of hepatitis B virus, the comparable immunogenicity and apparent antigenic homogeneity of HA Ags derived from various sources may simplify the approach to development of a vaccine against viral hepatitis, type A.     

Purified influenza virus hemagglutinin and neuraminidase are equivalent in stimulation of antibody response but induce contrasting types of immunity to infection.

BALB/c mice immunized with graded doses of chromatographically purified hemagglutinin (HA) and neuraminidase (NA) antigens derived from A/Hong Kong/1/68 (H3N2) influenza virus demonstrated equivalent responses when HA-specific and NA-specific serum antibodies were measured by enzyme-linked immunosorbent assays (ELISAs). Antibody responses measured by hemagglutination inhibition or neuraminidase inhibition titrations showed similar kinetic patterns, except for more rapid decline in hemagglutination inhibition antibody. Injection of mice with either purified HA or NA resulted in immunity manifested by reduction in pulmonary virus following challenge with virus containing homologous antigens. However, the nature of the immunity induced by the two antigens differed markedly. While HA immunization with all but the lowest doses of antigen prevented manifest infection, immunization with NA was infection-permissive at all antigen doses, although reduction in pulmonary virus was proportional to the amount of antigen administered. The immunizing but infection-permissive effect of NA immunization over a wide range of doses is in accord with results of earlier studies with mice in which single doses of NA and antigenically hybrid viruses were used. The demonstrable immunogenicity of highly purified NA as a single glycoprotein without adjuvant offers a novel infection-permissive approach with potentially low toxicity for human immunization against influenza virus.