• Journal of Veterinary Clinics
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• v.22 no.4
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• pp.348-352
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• 2005

We described a rapid, sensitive and reproducible real-time PCR assay for detection and quantitation of canine parvovirus type 2 in the feces of dogs with parvovirus infection. The method was demonstrated to be highly specific and sensitive, allowing a precise canine parvovirus type-2 quantitation over range of eight orders of magnitude from $10^2\;to\;10^9$ copies of standard DNA. Then, fecal samples from parvovirus infected dogs were analyzed by conventional PCR and real-time PCR. Real-time PCR is more sensitive than conventional PCR, allowing to detect low viral titers of CPV-2 in infected dogs. By real-time PCR, a wide range of parvovirus particles was found in the samples from $1.45\times10^6\;to\;9.45\times10^8$ copies/0.01g of feces. However, when dogs are in infection of parvovirus, it is difficult to prove that the numbers of peripheral blood leukocytes are correlated with those of fecal shedding virus.

• Korean Journal of Veterinary Research
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• v.49 no.3
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• pp.243-248
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• 2009

After the original identification of canine parvovirus (CPV) type 2 (CPV-2) in 1978, new antigenic variants such as CPV-2a, CPV-2b and CPV-2c have become widespread in the most countries. In this study, the genetic analysis of canine parvovirus was investigated in a total of 13 CPV vaccines, which have been licensed in Korea since late 1980s, and a field isolate of CPV from a dog with CPV infection clinical symptom. The partial VP2 gene of CPV was amplified and sequenced from 13 vaccine strains and one field isolate. The results showed that of the 13 vaccine strains, 10 strains belong to the CPV-2, 2 strains to CPV-2b, the remaining and one isolate to CPV-2a type, respectively. Several mutations of amino acids were detected at residues of the critical region of the commercial vaccine strains. These data suggest that new type of vaccines containing CPV-2a or CPV-2b/2c type may be required for the better prevention of new CPV infection in dog population in Korea, because CPV-2 contained in most licensed vaccines has been replaced by antigenic variants designated CPV-2a or CPV-2b/c in the worldwide dog population.

• Korean Journal of Veterinary Research
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• v.35 no.1
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• pp.75-85
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• 1995

An indirect immunofluorescent antibody test was applied to survey the antibody prevalence on five canine viruses including canine distempervirus(CDV), canine parvovirus(CPV), canine coronavirus(CCV), canine adenovirus type-2(CAV-2), canine parainfluenzavirus(CPIV) in dogs. The period studied was from October 1992 to June 1993. A total of 80 dog sera was collected from veterinary clinics in Kwangju and Seoul, and examined for the presence of virus antibodies. Immunofluorescent antibodies(IFA) to all viruses were present in a high percentage of 80 sera tested. Seventyfive(93.8%) showed detectable IFA against CPV, 67(83.8%) against CDV, 51(63.8%) against CCV, 42(52.5%) against CPIV and 34(42.5%) against CAV-2. These suggested that all viruses were endemic in the communities. IFA levels against each virus were also distributed fairly irregularly. IFAs for CDV and CPV were detected more frequently with a relatively high incidence in vaccinated group less than 1 years of age. IFAs for CAV-2 were detected more frequently with growing age. In the correlation of clinical signs and antibody prevalence, dogs that showed hematochezia and vomiting had high titers in the positive sera is noteworthy, particularly for CDV and CPV. The significance between dogs those who had diarrhea, dyspnea and salivation and those viruses were obscure.

• Korean Journal of Veterinary Research
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• v.64 no.1
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• pp.3.1-3.8
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• 2024

Canine distemper virus (CDV), canine adenovirus type 2 (CAV-2), canine parvovirus (CPV), and canine parainfluenza virus 5 (CPIV-5) are the major viral pathogens in dogs. Despite the availability of vaccines for dogs against these 4 viral pathogens, investigations of antibodies against these pathogens have rarely been reported in South Korea. In this study, we investigated the recent incidence of viral diseases in dogs and conducted sero-surveillance for CDV, CAV-2, CPV, and CPIV-5 in Korean dogs. The most frequently diagnosed canine viral disease in Korean dog samples from 2000 to 2022 was CPV infection, which accounted for 48.7% (464/953) of the cases. A total of 400 dog serum samples collected between 2019 and 2022 were screened for the presence of virus-neutralizing antibodies against CDV, CAV-2, CPV, and CPIV-5. The overall seropositivity rates for CDV, CAV-2, CPV, and CPIV-5 were 83.8%, 77.8%, 99.3%, and 82.0%, respectively. The protection rate against CPV was the highest (98.3%) and that against CAV-2 was the lowest (44.8%) in dog sera. Male and female dogs showed no significant differences in seropositivity rates. CDV and CPIV-5 seropositivity increased with age in dogs, and the highest incidence and seropositivity rates of CPV indicated that Korean dogs have been continuously exposed to wild CPV, and that CPV is a pathogen that urgently requires attention among canine viral diseases.

• Korean Journal of Veterinary Service
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• v.36 no.3
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• pp.187-192
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• 2013

For the monitoring of six viral disease (CIV: canine influenzavirus, CPIV: canine parainfluenzavirus, CHV: canine herpesvirus, CPV2: canine parvovirus type 2, CCoV: canine coronavirus, CNV: canine norovirus) inspections, a total of 300 samples were collected nasal or feces from the companion dogs of animal hospital (n=98) and the abandoned dogs of animal shelters (n=202) in Gwangju, Korea. Using PCR and RT-PCR, CPV2, CPIV and CHV were detected in 55 (18.3%), 11 (3.7%), 1 (0.3%), respectively. CPV2 was highly detected in May, October and November. and CPIV was highly detected in November. But those agents were not detected the virus in March and July. Based on the results of the investigation continuous monitoring for companion and abandoned dogs will be required.

• Korean Journal of Clinical Laboratory Science
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• v.55 no.1
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• pp.45-51
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• 2023

Canine parvovirus type 2 (CPV-2) and canine coronavirus (CCoV) are major pathogens that can induce gastroenteritis in dogs. They are highly contagious and have a high morbidity rate. There are no specific treatments available for them to date. Therefore, rapid and accurate diagnosis becomes essential. The rapid diagnostic test (RDT) for animals can be used widely in the field because it is fast and easy to use for diagnosis. Thus, this study aimed to clinically evaluate and confirm the clinical utility of CPV-2/CCoV RDT. The parameters evaluated included the limit of detection (LoD), cross-reactivity, interference, sensitivity, specificity, negative likelihood ratio (NLR), and kappa value. The results revealed that the LoD values for CPV-2 and CCoV were 9.7×10 50% tissue culture infectious dose (TCID₅₀)/mL and 2.5×10² TCID₅₀/mL, respectively. There was no cross-reactivity with nine pathogens or interference by interfering materials. The RDT showed a sensitivity of 90.0%, a specificity of 100.0%, NLR of 0.1, and a kappa value of 0.90 for diagnosing both viruses. In conclusion, CPV-2/CCoV RDT is useful as a screening test because of its high sensitivity, specificity, kappa value, and low NLR.

• Korean Journal of Veterinary Research
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• v.55 no.3
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• pp.163-167
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• 2015

Canine parvovirus (CPV) is a major diarrhea-causing agent in puppies. Since CPV type 2 (CPV-2) emerged in 1978, new antigenic variants including CPV-2a, CPV-2b, and CPV-2c have been identified in many countries. Two puppies died suddenly at a veterinary clinic in Gyeonggi province, South Korea. Two viruses were isolated in A72 cells, confirmed as CPV strains based on a CPV rapid kit and an indirect fluorescence test and designated QIACP1403 and QIACP1404. The nucleotide sequences of complete VP2 genes of QIACP1403 and QIACP1404 were determined, and the corresponding amino acid sequences were deduced. Molecular analyses revealed that the QIACP1403 and QIACP1404 isolates were type CPV-2b. Several mutated amino acids were detected on VP2 gene residues of the two isolates. Phylogenetic analyses showed that the two isolates were most closely related to strain CPV-BM11, which was isolated from Chinese dogs in 2011. Our results suggest that these isolates may be a candidate for a vaccine to prevent CPV infection in dogs after conducting passages of the isolates in an in vitro culture system.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.788-796
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• 2023

Canine parvovirus type 2 (CPV-2) has high morbidity and mortality rates in canines. Nonstructural protein 1 (NS1) of CPV-2 has endonuclease activity, initiates viral DNA replication, and is highly conserved. Thus, it is a promising target for antiviral inhibitor development. We overexpressed a 41.9 kDa active recombinant endonuclease in Escherichia coli and designed a nicking assay using carboxyfluorescein and quencher-linked ssDNA as substrates. The optimal temperature and pH of the endonuclease were 37℃ and pH 7, respectively. Curcumin, bisdemethoxycurcumin, demethoxycurcumin, linoleic acid, tannic acid, and α-tocopherol inhibited CPV-2 NS1 endonuclease with IC₅₀ values of 0.29 to 8.03 µM. The extracted turmeric, yerba mate, and sesame cake suppressed CPV-2 NS1 endonuclease with IC₅₀ values of 1.48, 7.09, and 52.67 ㎍/ml, respectively. The binding affinity between curcumin, the strongest inhibitor, and CPV-2 NS1 endonuclease by molecular docking was -6.4 kcal/mol. Curcumin inhibited CPV-2 NS1 endonuclease via numerous hydrophobic interactions and two hydrogen bonds with Lys97 and Pro111 in the allosteric site. These results suggest that adding curcuminoids, linoleic acid, tannic acid, α-tocopherol, extracted turmeric, sesame cake, and yerba to the diet could prevent CPV-2 infection.

• Journal of Veterinary Science
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• v.23 no.1
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• pp.14.1-14.11
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• 2022

Background: Carnivore protoparvovirus 1, also known as canine parvovirus type 2 (CPV-2), is the main pathogen in hemorrhagic gastroenteritis in dogs, with a high mortality rate. Three subtypes (a, b, c) have been described based on VP2 residue 426, where 2a, 2b, and 2c have asparagine, aspartic acid, and glutamic acid, respectively. Objectives: This study examined the presence of CPV-2 variants in the fecal samples of dogs diagnosed with canine parvovirus in Bogotá. Methods: Fecal samples were collected from 54 puppies and young dogs (< 1 year) that tested positive for the CPV through rapid antigen test detection between 2014-2018. Molecular screening was developed for VP1 because primers 555 for VP2 do not amplify, it was necessary to design a primer set for VP2 amplification of 982 nt. All samples that were amplified were sequenced by Sanger. Phylogenetics and structural analysis was carried out, focusing on residue 426. Results: As a result 47 out of 54 samples tested positive for VP1 screening, and 34/47 samples tested positive for VP2 980 primers as subtype 2a (n = 30) or 2b (n = 4); subtype 2c was not detected. All VP2 sequences had the amino acid, T, at 440, and most Colombian sequences showed an S514A substitution, which in the structural modeling is located in an antigenic region, together with the 426 residue. Conclusions: The 2c variant was not detected, and these findings suggest that Colombian strains of CPV-2 might be under an antigenic drift.

• Korean Journal of Veterinary Research
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• v.34 no.3
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• pp.537-547
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• 1994

Ninety seven cases of histopathologically diagnosed spontaneous canine parvovirus enteritis(CPE) were studied gross pathologically, histopathologically, immunohistochemically, to investigate histopathological types of small intestinal lesions, and antigen distributions in each pattern related to the infected age. And also, reliability of histopathological method in diagnosis of CPE was inspected with immunohistochemistry. The results were as follows : 1. Age-related occurring ratio in histopathologically diagnosed CPE was 53.6% in 4-8 weeks, 26.8% in 9-15 weeks, 8.25 in 16-19 weeks and 11.3% in 20-45 weeks of the clog age. 2. In histopathologic classification based on patterns of villi/crypts lesions of small intestine(jejunum), the ratio of A type (initial phase of necrosis of crypt epithelia, desquamated epithelial cells in the dilated lumen of the crypt) was 20.6%; the ratio of B type(middle phase of atrophy and fission of the villi, collapse of the mucosa, loss of normal crypt structure) was 62.9%, and C type(regenerative phase of the crypt architecture) was 16.5%. 3. The ratio of A, B, C type in 4-8 weeks old, respectively, was 23.5%, 61.5%, 15.4%; in 9-15 weeks old was 19.2%, 65.4%, 15.3% in 16-19 weeks old was 25.0%, 75.0%, 0.0%; and in 20-45 weeks old was 9.0%, 54.5%, 36.4%. 4. The antigen distribution in the nuclei of the crypt epithelial cells was higher than of the cytoplasm and numerous desquamated epithelial cells in dialated crypts in A type; The antigen cytoplasm and numerous desquamated epithelial cells in dialated crypts in A type; The antigen distribution in the nuclei of the collapsed crypt epithelial cells was not higher than that of the cytoplasm, crypts were lined by and filled with released viral antigens from the destructed epithelial cells in B type; and its distribution was also higher than in the epithelial cells adjacent to the tips of the villi, but it was not reacted in the regenerative crypt epithelial cells in C type. 5. Immunohistochemically detected antigen ratio in the small intestine of histopathologically diagnosed CPE was 94.6%, and this result indicates that histopathological diagnosis is very reliable method in diagnosis of CPE.