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1.
Biological material was taken from dogs with diarrhoea. Faecal samples were taken from within live animals and intestinal tract fragments (i.e. small intestine, and stomach) were taken from dead animals. In total, 18 specimens were investigated from dogs housed alone or in large groups. To test for the presence of the virus, latex (On Site Biotech, Uppsala, Sweden) and direct immunofluorescence tests were performed. At the same time, polymerase chain reaction (PCR) with primers complementary to a conservative region of VP1/VP2 was carried out. The products of amplification were analysed on 2% agarose gel. The purified products were cloned with the Template Generation System (Finnzymes, Espoo, Finland) using a transposition reaction and positive clones were searched using the 'colony screening by PCR' method. The sequencing gave 12 sequences of VP1/VP2 gene fragments that were of high similarity. Among the 12 analysed sequences, six exhibited 88% similarity, four exhibited 100% similarity and two exhibited 71% similarity.  相似文献   

2.
Biological material was taken from dogs with diarrhoea. Faecal samples were taken from within live animals and intestinal tract fragments (i.e. small intestine, and stomach) were taken from dead animals. In total, 18 specimens were investigated from dogs housed alone or in large groups. To test for the presence of the virus, latex (On Site Biotech, Uppsala, Sweden) and direct immunofluorescence tests were performed. At the same time, polymerase chain reaction (PCR) with primers complementary to a conservative region of VP1/VP2 was carried out. The products of amplification were analysed on 2% agarose gel. The purified products were cloned with the Template Generation System (Finnzymes, Espoo, Finland) using a transposition reaction and positive clones were searched using the `colony screening by PCR' method. The sequencing gave 12 sequences of VP1/VP2 gene fragments that were of high similarity. Among the 12 analysed sequences, six exhibited 88% similarity, four exhibited 100% similarity and two exhibited 71% similarity.  相似文献   

3.
犬细小病毒HZ0761株的分离与鉴定   总被引:1,自引:0,他引:1  
采集疑似细小病毒(CPV)感染犬的粪便,采用同步培养法接种胎猫肾细胞(F81)进行病毒分离鉴定。通过PCR检测、HA试验、IFA鉴定、电镜观察和空斑纯化,获得1株犬细小病毒,并命名为HZ0761。感染的F81细胞48h后出现明显的细胞病变;在病料和感染的F81细胞中均扩增出CPV VP2基因的特异性片段(221 bp);病毒液可凝集猪红细胞,血凝价为1∶28,其血凝性能被特异性抗体抑制;IFA可见特异性亮绿色荧光;电镜观察感染的F81细胞核内可见20 nm左右的病毒颗粒;病毒液的TCID50为10-4.8/mL,VP2基因序列分析显示该毒株为CPV-2 a型。  相似文献   

4.
A serological study of canine parvovirus (CPV) infections in a colony of dogs was conducted over a period of 8 months. Twenty-two of 24 adult dogs sampled initially had significant antibody titres to CPV. Nine litters of puppies wer e bled at fortnightly intervals and the sera tested for antibodies to CPV. Twenty-nine of 35 natural CPV infections observed were subclinical. A puppy in one litter developed vomiting and diarrhoea during the same period as seroconversion to CPV. Four puppies from a further litter developed histologically confirmed myocarditis. Serological testing of this latter litter indicated that the virus infections occurred between 2 weeks prior to and 1 week post whelping, and that clinical disease developed 20–40 days after viral infection. The mean half life of the decline of passively derived immunity to CPV was 8.3 days.  相似文献   

5.
Canine parvovirus (CPV) and feline panleukopaenia virus (FPLV) are two closely related viruses, which are known to cause severe disease in younger unvaccinated animals. As well as causing disease in their respective hosts, CPV has recently acquired the feline host range, allowing it to infect both cats and dogs. As well as causing disease in dogs, there is evidence that under some circumstances CPV may also cause disease in cats. This study has investigated the prevalence of parvoviruses in the faeces of clinically healthy cats and dogs in two rescue shelters. Canine parvovirus was demonstrated in 32.5% (13/50) of faecal samples in a cross sectional study of 50 cats from a feline only shelter, and 33.9% (61/180) of faecal samples in a longitudinal study of 74 cats at a mixed canine and feline shelter. Virus was isolated in cell cultures of both canine and feline origin from all PCR-positive samples suggesting they contained viable, infectious virus. In contrast to the high CPV prevalence in cats, no FPLV was found, and none of 122 faecal samples from dogs, or 160 samples collected from the kennel environment, tested positive for parvovirus by PCR. Sequence analysis of major capsid VP2 gene from all positive samples, as well as the non-structural gene from 18 randomly selected positive samples, showed that all positive cats were shedding CPV2a or 2b, rather than FPLV. Longitudinally sampling in one shelter showed that all cats appeared to shed the same virus sequence type at each date they were positive (up to six weeks), despite a lack of clinical signs. Fifty percent of the sequences obtained here were shown to be similar to those recently obtained in a study of sick dogs in the UK (Clegg et al., 2011). These results suggest that in some circumstances, clinically normal cats may be able to shed CPV for prolonged periods of time, and raises the possibility that such cats may be important reservoirs for the maintenance of infection in both the cat and the dog population.  相似文献   

6.
Fifty-five canine parvovirus type 2 (CPV) samples, 12 fecal specimens and 43 cell culture isolates, were examined for their genetic characteristics of VP2 gene. They were collected from the diseased dogs at various districts of Japan during 27 years from 1980 to 2006. A fragment of VP2 gene was analyzed by restriction fragment length polymorphism assay and DNA sequencing. The original antigenic type 2 of CPV (CPV-2) was no longer found in the samples since 1984, and two antigenic variants CPV-2a and CPV-2b replaced CPV-2 as predominant types for about 5 years from 1982. A new genetic variant of prototype CPV-2a with non-synonymous substitution at the VP2 amino acid residue 297 from Ser to Ala was first detected in 1987. New CPV-2b with the same amino acid substitution at position 297 as new CPV-2a was also detected from the samples collected in 1997. Since then new CPV-2b has been the predominant CPV over the field of Japan. Several additional amino acid substitutions were detected in the VP2 gene of some recent CPV strains. Neither CPV-2c(a), CPV-2c(b), nor "Glu-426" of the antigenic variants previously found outside the country was detected in any samples tested. Reactivity of new CPV-2a and 2b variants against antibodies produced by the current vaccine products was determined by a cross hemagglutination-inhibition test. The recent field CPV isolates reacted more efficiently to the antibodies produced in dogs vaccinated with the new CPV-2b vaccine strain than the conventional CPV-2 vaccine strain.  相似文献   

7.
Canine parvovirus type 2 (CPV-2) emerged in late 1970s causing severe epizootics in kennels and dog shelters worldwide. Soon after its emergence, CPV-2 underwent genetic evolution giving rise consecutively to two antigenic variants, CPV-2a and CPV-2b that replaced progressively the original type. In 2000, a new antigenic variant, CPV-2c, was detected in Italy and rapidly spread to several countries. In comparison to the original type CPV-2, the antigenic variants display increased pathogenicity in dogs and extended host range, being able to infect and cause disease in cats. Epidemiological survey indicate that the newest type CPV-2c is becoming prevalent in different geographic regions and is often associated to severe disease in adult dogs and also in dogs that have completed the vaccination protocols. However, the primary cause of failure of CPV vaccination is interference by maternally derived immunity. Diagnosis of CPV infection by traditional methods has been shown to be poorly sensitive, especially in the late stages of infections. New diagnostic approaches based on molecular methods have been developed for sensitive detection of CPV in clinical samples and rapid characterisation of the viral type. Continuous surveillance will help assess whether there is a real need to update currently available vaccines and diagnostic tests.  相似文献   

8.
In order to establish a TaqMan MGB fluorescent-quantitative PCR (FQ-PCR) assay for detecting canine parvovirus (CPV) specifically, sensitively and rapidly, a highly sensitive and specific TaqMan MGB FQ-PCR assay was developed using the specific primers and TaqMan MGB probe designed basing on the conservative sequences of VP2 gene of CPV in GenBank. The sensitivity, specificity and repetition assay of FQ-PCR assay were tested, and 46 clinic suspicious CPV infected samples were detected by the FQ-PCR assay in contrast to the routine PCR method. The results indicated that the FQ-PCR was successfully established. The developed FQ-PCR assay was able to detect as little as 1×101copies/μL of recombinant pGEX-T/CPV plasmid DNA, and the sensitivity of which was 100 times more than that of the routine PCR. The specificity assay exhibited that positive signals could be obtained from recombinant pGEM-T/CPV plasmid, but not from the genomic DNA or total cDNA of the other 5 kinds of pathogenic microorganism acting as the controls. The repetition tests were carried out by detection repeated 3 times for 3 different concentrations of recombinant pGEX-T/CPV plasmid, and the results indicated that the FQ-PCR was reproducible. Twenty-three positive results from 46 clinic suspicious CPV infected samples were obtained, which showed the better sensitivity than that of the routine PCR, with 19 positive samples from the same 46 suspected samples. The study suggested that the CPV FQ-PCR method was successfully established, and suitable for clinic rapid diagnosing of CPV and early detection of latent infection.  相似文献   

9.
Twelve dogs dead as consequence of natural infection caused by canine parvovirus (CPV) type 2a (n=4), type 2b (n=4) or type 2c (n=4) were investigated for determining the viral DNA loads in different tissue samples. By means of a real-time PCR assay, CPV DNA was detected in all tissues examined, with the highest titres observed in the lymphoid tissue and the lowest loads in the urinary tract. Surprisingly, the nervous tissue was found to contain considerable amounts of CPV nucleic acid. Similar patterns of tissue distribution were observed in all the examined dogs irrespective of the antigenic variant causing the disease.  相似文献   

10.
抗犬细小病毒免疫球蛋白临床应用研究   总被引:2,自引:0,他引:2  
用犬细小病毒性肠炎免疫球蛋白注射液对382例临床诊断为犬细小病毒性肠炎病犬进行了治疗,结果治愈344只,治愈率为90.05%;早期治疗效果更好,小于3个月的幼犬治愈率为93.88%。对临床病例进行分析,进一步证明该产品对犬细小病毒病的治疗是有效的。  相似文献   

11.
Canine parvovirus (CPV) is highly contagious and can cause haemorrhagic enteritis and myocarditis in dogs. To understand the current epidemic situation of CPV in Jilin Province, China, a total of 44 fecal or intestinal tissue samples of pet dogs suspected of being infected with CPV from February 2018 to November 2019 in Changchun and Liaoyuan City, Jilin Province were collected.All of the 44 collected samples were tested positive to CPV-2 by a PCR assay. The sequencing and analyzing of complete VP2 genes showed that CPV-2c was the most prevalent variant (n = 31;70.4 %), followed by new-CPV-2a (n = 8;18.2 %), new-CPV-2b (n = 4; 9.1 %) and CPV-2 (n = 1; 2.3 %). Phylogenetic analysis revealed that the 31 CPV-2c strains in our study are closely related to local CPV-2c isolates in cluster I. The VP2 protein of the acquired CPV 2c strains all possessed the substitutions Ala5Gly, Phe267Tyr, Tyr324Ile, and Gln370Arg only one with a novel Arg481Lys mutation. These findings demonstrate that CPV-2c was the most prominent type of CPV circulating in Jilin in 2018–2019, clustered in a separate group that is far from the vaccine strains and suggest that further and extensive epidemiological investigation among pet dogs are warranted to provide information for usage and research of current vaccines.  相似文献   

12.
成都地区犬细小病毒VP2基因克隆分析及基因型鉴定   总被引:1,自引:1,他引:0  
根据GenBank中犬细小病毒(canine parvovirus,CPV)VP2基因序列设计合成两对特异性引物1F/1R和2F/2R,从疑似CPV感染病犬的粪便病料中提取DNA作为模板,分段扩增涵盖VP2基因的两个片段,大小分别为1325和758 bp,并进行克隆、测序,通过拼接得到11条长度为1755 bp的VP2基因完整序列。核苷酸同源性分析表明,扩增得到的11个完整VP2基因序列与GenBank中发布的21株国内外参考毒株比较,核苷酸同源性为96.2%~99.8%。采用DNAStar软件分析,预测VP2蛋白可能成为B细胞表位的区段位于Met1-Val38、Met73-Val82、Met96-Ala103、Lys151-Thr170、Gly235-Phe243、Leu294-Phe303、Ala359-Thr399、Ile469-His483、Ala503-Arg520、Lys570-Tyr584。将扩增获得的VP2基因编码的氨基酸序列与CPV参考毒株进行比较,第426位和第555位氨基酸残基分别为Asp和Val,鉴定出本试验得到的CPV基因型均为2a型,初步证实成都地区仍以CPV-2a为主要流行毒株。  相似文献   

13.
Toxoplasma infection as detected by the immunofluorescent antibody (IFA) test was found in 13.2% of 448 dogs examined at the Purdue University Small Animal Clinic. Only titres of 1/64 and above were considered positive, but lesser titers were encountered more frequently. The highest titer observed was 1/1024 in 2 dogs one of which had idiopathic epilepsy and the other had dirofilariasis as well as hip dysplasia. The incidence of positive sera from male and female dogs were 11.7 and 14.5%, respectively. The highest frequency of infection occurred in young dogs up to 4 years of age and the lowest was in older animals. The presence of the high toxoplasmosis IFA titers in the sera of dogs seems to be associated with other disease conditions. Stress such as joint dislocations, fractures, helminth parasitism, and concomitant bacterial and viral infections, etc., was observed in 62.7% of the positive cases. Presence of tumors and renal disease conditions were associated with 28.8 and 5.2%, respectively, of the positive sera.  相似文献   

14.
Inactivated canine parvovirus (CPV) and inactivated feline panleukopenia virus (FPV) vaccines were evaluated in dogs. Maximal serologic response occurred within 1-2 weeks after vaccination. Antibody titers then declined rapidly to low levels that persisted at least 20 weeks. Immunity to CPV, defined as complete resistance to infection, was correlated with serum antibody titer and did not persist longer than 6 weeks after vaccination with inactivated virus. However, protection against generalized infection was demonstrated 20 weeks after vaccination. In unvaccinated dogs, viremia and generalized infection occurred after oronasal challenge with virulent CPV. In contrast, viral replication was restricted to the intestinal tract and gut-associated lymphoid tissue of vaccinated dogs. Canine parvovirus was inactivated by formalin, beta-propiolactone (BPL), and binary ethylenimine (BEI) in serum-free media; inactivation kinetics were determined. Formalin resulted in a greater loss of viral HA than either BEI of BPL, and antigenicity was correspondingly reduced.  相似文献   

15.
This study was aimed to establish a double TaqMan MGB Real-time PCR assay to simultaneously and specifically detect canine distemper virus (CDV) and canine parvovirus (CPV) in one reaction.Two pairs of specific primers for CDV and CPV,along with two TaqMan MGB probes for each virus were designed in the assay basing on CDV H gene and CPV VP2 gene sequences.The specificity,sensitivity and repetition of the double TaqMan MGB Real-time PCR assay were tested,and 48 samples taken from clinic suspicious CDV and CPV infected canines had been testified by the established double TaqMan MGB Real-time PCR.The results indicated that the doulde TaqMan MGB Real-time PCR assay was successfully established,and the number of standard curve correlation (R2) of CDV and CPV were 0.997 and 0.993,respectively.The specificity of the double TaqMan MGB Real-time PCR assay revealed that amplifications were showed on CDV and CPV samples,but other pathogens and negative controls had no amplifications;The sensitivity of CDV and CPV were both 10 copies/μL.Meanwhile,14 CDV positive samples,19 CPV positive samples and 4 CDV/CPV double positive samples were detected,which were consistent with the results of the sequencing.Therefore,the established double TaqMan MGB Real-time PCR assay had high sensitivity,specificity and flux accurate quantitative,which could be applied to clinical CDV/CPV infection each periods.  相似文献   

16.
Loop-mediated isothermal amplification (LAMP) is a novel, sensitive, and rapid technique for detection of genomic DNA. The end-product of the technique is a white precipitate of magnesium pyrophosphate that is visible without the use of gel electrophoresis. The LAMP method was applied to the detection of canine parvovirus (CPV) genomic DNA. A set of 4 primers, 2 outer and 2 inner, were designed from CPV genomic DNA targeting the VP2 gene. The optimal reaction time and temperature for LAMP were determined to be 60 minutes and 63 degrees C. On the basis of results for 50 canine fecal samples using polymerase chain reaction (PCR) analysis as the gold standard, the relative sensitivity of LAMP was 100% and the relative specificity was 76.9%. The detection limit of the LAMP method was 10(-1) median tissue culture infective doses (TCID50)/ml, compared with 10 TCID50/ml for PCR analysis. In addition to the advantage resulting from visual detection of the end product, the LAMP method is very rapid, requiring only 1 hour to complete. This assay would be a viable alterative to PCR analysis for diagnosis of CPV infection in dogs. The LAMP method holds promise for use as a diagnostic assay for CPV detection in a clinical setting.  相似文献   

17.
This study aimed to confirm the possible presence of bacteria in the liver of healthy dogs. Laparotomy was performed in 20 animals admitted for routine abdominal surgery. To be selected for the study, dogs had to be healthy adults without clinical liver disease, signs of infection or macroscopic liver abnormalities. Biopsy samples were histologically and bacteriologically examined. Bacteriological analysis was negative for the livers of eight of the dogs. The remaining animals harboured a diverse bacterial flora in their liver. Twelve bacterial species were identified. Histology showed that the livers of 19 dogs had minor or no abnormalities, and only one animal had interstitial fibrosis and trabecular disarrangement. Histological changes were not related to the presence of bacteria. Thus the results showed that the liver of healthy dogs may harbour different bacterial species. These microorganisms did not cause any detectable manifestation of disease, despite being potential pathogens.  相似文献   

18.
ELISA法检测犬腹泻粪样中的犬冠状病毒   总被引:2,自引:0,他引:2  
用FE细胞增殖犬冠状病毒(CCV)参考株,分别免疫家兔和BALB/c小鼠制备CCV多抗和单抗,建立了夹心ELISA及Dot-ELISA诊断方法。在检测的84例犬腹泻粪样中,多抗、单抗夹心法显示CCV阳性16例,Dot-ELISA阳性13例,后13例包括在前16例中。从84例腹泻犬粪样中随机取38例作CCV、犬细小病毒(CPV)双项检测,CCV阳性16例,CPV阳性6例,CCV、CPV混合感染4例。结果显示,在南京地区流行的犬腹泻中,CCV感染比例有超过CPV的趋势。  相似文献   

19.
Conditions for canine parvoviral hemagglutination (HA) and hemagglutination-inhibition (HI) reactions were defined. The HA phenomena were used to differentiate canine parvovirus (CPV) from feline panleukopenia virus (FPV), mink enteritis virus (MEV), and minute virus of canines. Serologic comparisons of the CPV, FPV, and MEV by HA-HI and serum-neutralization tests indicated that CPV, FPV, and MEV were antigenically similar but were different from minute virus of canines. Diagnostic application of HA tests to fecal samples from acute cases of enteritis was discussed. Combinating HA tests with HI tests on fecal samples provided a rapid and specific diagnostic method for CPV infection. Secular seroprevalence studies indicated the emergence of CPV infeciton in the United States dog population-at-large in 1978.  相似文献   

20.
The relationship between maternally derived antibody (MDA) levels and protection to canine parvovirus (CPV) infection in pups is reported. Twelve pups with a wide range of haemagglutination inhibiting (HI) titres of MDA to CPV were divided into four groups, with each group balanced for antibody titres. The dogs were inoculated with a field CPV-2b strain and clinical signs, virus shedding and antibody response were assessed. The CPV was not detected in the faeces of dogs with HI titres of 320 at any time. In dogs with HI titres up to 160, active CPV replication after challenge was demonstrated by real-time polymerase chain reaction. The successful infection of dogs with HI titres of 80 and 160 was confirmed by seroconversion, evaluated at day 14 post-infection. These findings demonstrated that CPV infection could also occur in the presence of MDA HI titres (> or =80) usually considered fully protective.  相似文献   

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