犬冠状病毒病的病原,诊断及免疫研究进展

犬冠状病毒病是由犬冠状病毒（ＣａｎｉｎｅＣｏｒｏｎａｖｉｒｕｓ,ＣＣＶ）引起犬发生的一种以胃肠炎为主要症状的高度接触性传染病。该病最初由Ｂｉｎｎ等［１］首先报道。血清学调查研究发现,该病呈世界性分布,我国也有军犬、警犬、实验犬和民用犬的发病报道,且有流行趋势。犬冠状病毒病在临床上主要表现为呕吐、血便和严重脱水,对幼犬危害严重,发病率和死亡率都很高,是当前对养犬业危害较大的疾病之一。目前国内随着犬瘟热、犬细小病毒性肠炎等疫苗的研制成功和广泛应用,犬这些急性恶性传染病已基本得到了控制,但对于犬冠状病…     

犬冠状病毒病的诊断与控制

犬冠状病毒病是由犬冠状病毒引起的一种犬的急性胃肠道传染病。它以传播迅速、致死率高,发病后呈不同程度的胃肠道炎症为特征。1病原犬冠状病毒(CCV)是冠状病毒科冠状病毒属中的一个新成员。电镜下病毒呈圆形(直径80～100nm),或椭圆形(长180～200nm,宽75～80nm),有囊膜,表面有长约20nm的纤突,纤突末端呈球状,含单股RNA。CCV对热、紫外线、福尔马林、石炭酸、乙醚、氯仿及去氧胆酸盐、来苏尔、0.1%过氧乙酸、1%克辽林等敏感。病毒能在许多犬的原代细胞或传代细胞上生长。病毒主要存在于感染犬的肠内容物中和肠上皮内,在肠系膜淋巴结及其…     

犬猫冠状病毒病

由犬猫冠状病毒感染导致的犬猫冠状病毒病对宠物危害较大,不仅影响宠物行业的健康发展,还对人类健康和公共卫生安全构成潜在威胁。本文从病原学、临床症状与病理变化、诊断方法等方面分别对犬冠状病毒病和猫冠状病毒病进行介绍,并对犬猫冠状病毒病的防治进行概述,以期为犬猫养殖者、饲养者及研究人员提供参考。     

警犬冠状病毒病诊断报告

1989年秋季,黑龙江省某警犬基地■犬陆续发生了以出血性肠炎为主要临床症状的传染病,累计发病53条,发病率及死亡率极高,对幼犬构成了毁灭性的威胁。木病经多次病原检查,确诊为犬冠状病毒感染。一、疫情发生及流行情况该基地共有各类警犬156条,品种为德国牧羊犬及中国杂交狼种犬。管理情况为成犬及四月龄以上幼犬单圈饲养,二月龄以上幼犬每2～4条为一圈饲养,二月龄以下幼犬随母犬一同饲养。各年龄组的犬营养状况均良好,发育正常,已按免疫程序接种了犬细小病毒、传染性肝炎、犬瘟热等疫苗,接种疫苗后无任何异常反应。     

幼狐冠状病毒病的诊断与防控

狐冠状病毒是一种危害严重的接触性传染病,引起狐急性胃肠炎为主要特征的病毒性传染病,临床上主要表现为剧烈腹泻、呕吐。剖检可见肠黏膜坏死、脱落,肠系膜淋巴结肿大等病理变化。该病主要侵害幼狐,死亡率高,成年狐和育成狐感染一般无死亡。2019年8月齐齐哈尔市某养殖场发生幼狐冠状病毒病,发病率和死亡率均较高,养殖户经济损失较大,经实验室诊断,制定了科学的防治方案,最终疾病得到有效防治,现将诊治情况介绍如下。     

犬冠状病毒病的诊断与治疗

本病的病原为冠状病毒科冠状病毒属中的成员。本病毒对犬、貉、狐狸等犬科动物均感染,不同品种、性别、年龄的犬都可感染,但幼犬最易感,发病率和死亡率都很高。此病不分季节,一年四季均能发生,但以冬季多发。气候突变,卫生条件差,犬群密度过大,断奶转舍,长途运输等均可诱发本病。病犬和带毒犬是主要传染源。传染的途径是经呼吸道、消化道向外界排出病毒,污染饲料、饮水、用具、犬舍、运动场等,从而传染给健康犬和其他易感动物。     

犬细小病毒病的诊治

犬细小病毒病的诊治何伟（汤原县畜牧局１５４７００）１９９０年，据我兽医门诊统计．共诊治犬１２４例．其中以发热、废食、出血性腹泻、白细胞显。著减少为其特征的占有１０４例．经多方诊治为是犬细小病毒病．我们采用了以输液为主的综合疗法，使治愈率达到８１．５％...     

Course of experimental infection of canine leishmaniosis: Follow-up and utility of noninvasive diagnostic techniques

This study compares the utility of a molecular diagnosis of experimental CanL on non-invasive samples (urine, conjunctival (CS), oral (OS) and vulvar (VS) swabs) with that of traditional invasive techniques during the course of infection. Eight dogs were experimentally infected with Leishmania infantum and followed monthly for 12 months to assess clinical, clinicopathological, immunological and parasitological variables. Active infection was produced in 100% of the dogs. The animals showed positive bone marrow (BM) cytologies and cultures, clinical signs, clinicopathological abnormalities and a high specific humoral immune response. The infection was detected at 90 days post-infection (p.i.) by real-time quantitative PCR (rtQ-PCR) on BM in all dogs and in blood in 2 dogs, while anti-L. infantum antibody seroconversion occurred between Days 120 and 180 days p.i. The tissue with the highest L. infantum kDNA load, as detected by rtQ-PCR, was BM (range 381.5–70,000 parasites/ml at the study end), this sample type showing greater sensitivity than peripheral blood (PB). The vulvar swabs used here for the first time to quantify parasite loads in dogs revealed a greater load than oral and conjunctival swabs at one year p.i. Urine samples showed the lowest concentrations of L. infantum DNA (maximum: 8.57 parasites/ml). Our results suggest that for the early detection of infection, adding to serology a test such as rtQ-PCR on OS or VS improves sensitivity and specificity.     

犬常见传染病诊断基因芯片的研究与应用

根据PCR技术扩增出犬腺病毒（CAV）ORF1（p-Ⅷ）基因、犬细小病毒（CPV）VP2基因、鸡血红蛋白的珠蛋白基因（GLOBc）各保守基因片段；采用RT—PCR扩增出犬冠状病毒（CCV）纤突蛋白（S）基因、犬瘟热病毒（cDV）融合蛋白（F）基因、犬副流感病毒（CPIV）核衣壳结构蛋白（NP）基因、狂犬病病毒（RV）核蛋白（N）基因的各一段保守序列，克隆荻取质粒。通过微量点样技术将这些质粒作为探针点在硝酸纤维素膜上，产生二维DNA探针阵列，制作成诊断基因芯片。对360份待检样品匀浆后提取核酸作为模板，扩增相应保守基因片段。通过生物素标记PCR（RT—PCR）技术，将所获得的扩增产物与诊断基因芯片进行特异性的逆向点杂交，然后用扫描仪对芯片进行扫描分析、判断。结果表明，此方法比病毒分离、HI、PCR或RT—PCR方法灵敏度高、特异性强，平均检出率要高20％以上，并可同时对犬多种疫病进行快速诊断。     

Serological prevalence of canine respiratory coronavirus

Canine respiratory coronavirus (CRCoV) has recently been detected in dogs; it is a group 2 coronavirus showing similarity to bovine coronavirus (BCoV) but is distinct from canine enteric coronavirus (CECoV). CRCoV may play an important role in canine infectious respiratory disease (CIRD) either by predisposing to further and potentially more serious viral and bacterial infections or possibly as a primary pathogen. The prevalence of serum antibodies to CRCoV, in a population of dogs in the south east of England, has been shown previously to be 30.1% on the first day of entry to a rehoming kennel [Erles, K., Toomey, C., Brooks, H.W., Brownlie, J., 2003. Detection of a group 2 coronavirus in dogs with canine infectious respiratory disease. Virology 310, 216-223]. The purpose of this study was to establish the prevalence of CRCoV in the general canine population within as well as outside the UK. An ELISA, used to test for the presence of antibodies to CRCoV in canine serum samples, identified seropositive dogs in UK, USA, Canada, Republic of Ireland and Greece. The development of an ELISA based on CRCoV antigen and immunofluorescence assay are described here. 54.7% (547/1000) of North American and 36.0% (297/824) of United Kingdom dogs were seropositive for CRCoV. The age and geographical distribution of seropositive dogs was also assessed. The cross-reactivity demonstrated between CRCoV antibodies from different countries and a UK viral isolate suggests immunological similarity. The overall prevalence of this virus in both North America and the UK suggests that CRCoV has international significance and that further epidemiological studies are required.     

Serological prevalence of canine respiratory coronavirus in southern Italy and epidemiological relationship with canine enteric coronavirus.

Canine respiratory coronavirus (CRCoV) has been detected in dogs suffering from respiratory disease and is thought to be involved in canine infectious respiratory disease (CIRD) complex. Canine enteric coronavirus (CECoV) is a widespread pathogen of dogs, responsible for mild to severe diarrhea in pups. The purpose of this study was to establish the seroprevalence of CRCoV in Italy and its relationship to CECoV type II seroprevalence. The age and year of sample collection from seropositive dogs was also assessed. Of adult domestic dogs, 23.3% had antibodies to CRCoV, compared with 86.1% with antibodies to CECoV. Amongst a population of kenneled pups, 4.0% had antibodies to CRCoV, and 97.0% had antibodies to CECoV.     

Intestinal infection of neonatal dogs with canine coronavirus 1-71: studies by virologic, histologic, histochemical, and immunofluorescent techniques.

Enteritis induced in neonatal dogs by oral inoculation of coronavirus 1-71 was studied by virologic, histologic, histochemical, and immunofluorescent antibody methods. The enteritis, accompanied by diarrhea, developed in 4 to 7 days and was characterized by atrophy and fusion of intestinal villi and deepening of crypts, increase in cellularity of the lamina propria, flattening of epithelial cells, and discharge of goblet cells. Intra-epithelial enzyme activities generally were depressed. Specific immunofluorescent antibody reactions were present in villous epithelium of the duodenum starting on postinoculation day 2 and of the ileum on day 4. Epiehtlium of the colon showed no reaction. Virus was present in the feces for 6 to 9 days and was recovered from the small and large intestines from day 2 through day 10. The infection was not fatal and was self limiting; the diarrhea stopped between 1 and 2 weeks. The intestinal mucosa also started recovering by the end of week 1, proceeding caudally from the duodenum.     

Experimental infection of dogs with a novel strain of canine coronavirus causing systemic disease and lymphopenia

A pantropic canine coronavirus (CCoV) strain (CB/05) has been recently associated to a fatal outbreak of systemic disease in young dogs. We report the clinical, virological and serological findings in dogs experimentally infected with strain CB/05. The dogs, three 2.5-month-old and two 6-month-old pups, were successfully infected, shedding viral RNA with their faeces for the entire observation period (21 days) and displaying systemic clinical signs resembling those observed during the course of natural infection. Leucopenia (acute lymphopenia) occurred in all infected dogs, with values dropping below 60% of the initial counts. Considering the severity of the CB/05-induced disease, two of the youngest pups were euthanized for ethical reasons at days 8-9 postinfection, whereas the other pups underwent a slow but progressive improvement of their clinical status with complete recovery. At postmortem examination, remarkable lesions were observed in the internal organs of the euthanized pups, that tested positive for CCoV by real-time RT-PCR and virus isolation on cell cultures. All pups seroconverted for CCoV, as shown by the high optical density values and antibody titres detected by ELISA and virusneutralisation tests, respectively. The present study confirms that strain CB/05 is highly pathogenic for dogs, being able to induce a severe disease (and in some cases the death) even in experimental conditions.