Canine Parvovirus Research Articles

A comprehensive molecular survey of viral pathogens associated with canine gastroenteritis.

Viral pathogens are the primary cause of canine gastroenteritis. However, few structured comprehensive studies on the viral etiology of canine gastroenteritis have been conducted. In this study, 475 rectal swabs collected over three years (2018-2021) from clinical canine gastroenteritis cases were screened for the presence of six major enteric viruses - canine parvovirus 2 (CPV-2), canine distemper virus (CDV), canine adenovirus 2 (CAdV-2), canine coronavirus (CCoV), canine astrovirus (CaAstV), and canine rotavirus (CRV) - by real-time PCR. The most frequently detected virus was CPV-2, which was present in 64.8% of the samples (subtype 2a, 21.1%; 2b, 77.4%; 2c, 1.5%), followed by CDV (8%), CaAstV (7.2%), CCoV (5.9%), and CAdV-2 (4.6%). Two to four of these viruses in different combinations were found in 16.8% of the samples, and CRV was not detected. The complete genome sequences of Indian isolates of CDV, CCoV, and CaAstV were determined for the first time, and phylogenetic analysis was performed. This study highlights the need for routine prophylactic vaccination with the appropriate vaccines. Notably, 70.3% of animals vaccinated with DHPPiL were found to be positive for at least one virus. Hence, regular molecular analysis of the prevalent viruses is crucial for addressing vaccination failures.

Dietary yeast beta 1,3/1,6 glucan supplemented to adult Labrador Retrievers alters peripheral blood immune cell responses to vaccination challenge without affecting protective immunity.

Yeast-derived 1,3/1,6 beta-glucans may alter host immunity to produce robust and quickly resolved responses that align with companion animal health goals. In adult dogs, immunomodulation by yeast 1,3/1,6 beta-glucans in extruded kibble diet have not been well-documented. The study objective was to evaluate systemic immune responses in dogs fed kibble diets with two yeast 1,3/1,6 beta-glucans doses before and after vaccine challenge. Twenty-four adult Labrador Retrievers were assigned to 3 dietary treatments consisting of a basal diet (control) supplemented with 0.012 or 0.023% (0.5 or 1X, respectively) yeast 1,3/1,6 beta-glucan with equal sex representation within each treatment (8 dogs/diet). Animals were fed experimental diets for a 29d acclimation period, after which baseline blood samples were collected before administration of a combination canine distemper virus, parvovirus, and adenovirus-2 vaccine. Blood samples were collected weekly for 21d following vaccination with whole blood for CBC analysis, serum for titer and cytokine assays, and peripheral blood mononuclear cells (PBMC) isolated for flow cytometric immune cell profiling. Data were analyzed using the MIXED procedure with diet and timepoint fixed effects. Serum titer was analyzed by Kruskal-Wallis test (SAS 9.4; P≤0.05). Prior to vaccination, beta-glucan diets did not affect serum cytokines, antibody titer, or immune cell populations. In the first 7 days post-vaccination (dpv), PBMC CD21 low B cells increased in 36.5-58.1% in all groups but the magnitude of change was lesser in the 0.5X beta-glucan diet resulting in 25.6% lower CD21 low populations compared to control-fed dogs (P=0.007). By 21dpv, B cell populations recovered to baseline levels in dogs fed 1X beta-glucan, but CD21 high cells remained elevated 50.5% in dogs fed 0.5X beta-glucan diets compared to baseline (P<0.0001). While no differences in serum titer or cytokines were observed, feeding both beta-glucan diets maintained stable blood monocytes whereas a 53.0% decrease between baseline and 14dpv was observed in control-fed dogs (P=0.01). Collectively, these outcomes suggest that a 1X dose of 1,3/1,6 yeast beta-glucan in extruded kibble diets altered monocytes associated with trained immunity, did not reduce PBMC CD21 low B cell responsiveness, and simultaneously contributed to B cell population resolution by 21dpv in adult dogs. Additional research to assess the functionality of these changes is needed.

Thyroid pathology in canine parvoviral infection

The hypothalamic-pituitary-thyroid axis is suppressed by pro-inflammatory mediators in systemic disease, which affects the thyroid hormone level. Canine parvovirus is one of the important infectious diseases which causes profound morbidity as well as mortality in dogs. It is found that canine parvovirus infection can result in non-thyroidal sickness syndrome. The relation between thyroid pathology and canine parvovirus infection will pave the way for therapeutic and preventive measures for this infectious disease. This study was conducted on 61 dog carcasses brought to the Department of Veterinary Pathology, College of Veterinary and Animal Sciences, Pookode during one year period. Among 61 cases, nine were found to be positive for canine parvovirus which constitutes an incidence of 14.75 per cent. Analysis of gross and histopathological lesions in canine parvovirus positive cases was the goal of this investigation. The gross lesions observed were paleness and nodular growth and histopathological lesions encountered were lymphocytic thyroiditis, colloidal goiter, c cell hyperplasia, severe fibrotic changes and neoplastic lesions. Further research is required to understand the pathophysiology of the euthyroid sick syndrome in canine parvoviral infection.

Exposure of dogs and wild carnivores to canine distemper virus, canine parvovirus, Leishmania infantum, and Toxoplasma gondii in the Xingu River basin, Brazilian Amazon: Prevalence, spatial distribution, and association with land cover types

ABSTRACT Infectious diseases transmitted by domestic dogs can have important consequences for wildlife health. This study aimed to investigate the exposure to four selected pathogens in dogs and wild carnivores in six municipalities in the Xingu River Basin (Pará state, Brazil). The prevalence of positive animals, their spatial distribution, and the association with land cover types were analyzed. Blood samples from 298 dogs and 11 free-ranging wild carnivores were tested through serological diagnoses. The seroprevalence to canine distemper virus, canine parvovirus, Leishmania infantum, and Toxoplasma gondii was 68.6, 75.4, 14.8, and 47.1%, respectively. The seroprevalence to canine distemper virus and T. gondii was significantly higher in dogs than in wild carnivores. Spatial analyses revealed a broad distribution of seropositive animals, except for animals seropositive to L. infantum, which were concentrated in the southern region close to the margins of the Xingu River. Spatial clusters of seropositive animals were detected for all tested pathogens, indicating areas with a greater risk of exposure. Positive results for canine distemper virus, T. gondii, and L. infantum were associated with different types of land cover, and thus were considered risk factors for pathogen exposure. The high seroprevalence of dogs to canine distemper virus and to canine parvovirus are concerning, suggesting risks of transmission to wild species inhabiting areas close to the surveyed communities.

Ozone therapy: protocol for treating canine parvovirus infection.

Canine Parvovirus infection is a disease caused by Canine Parvovirus (CPV) that results in hemorrhagic gastroenteritis and secondary infections, mainly in puppies between six weeks and six months old that are not immunized. Since there is no specific treatment for the condition, supportive therapy based on antibiotics, antiemetics, and non-steroidal anti-inflammatory drugs is traditionally used. Ozone therapy is an economical treatment that has bactericidal, fungicidal, and antiviral properties, besides promoting oxygenation and tissue regeneration, as well as anti-inflammatory and analgesic effects, and was used as a complementary therapy in this study. Therefore, four mixed-breed dogs, aged between 2 and 3 months, with no previous immunization against CPV and testing positive for the virus in a rapid test were selected. The animals were randomly distributed into two groups, being 1: the control group (n=2) that received only supportive treatment; and 2: the experimental group (n=2), that in addition to conventional therapy received intravenously 500 mL of ozonized Ringer's Lactate solution. Before treatment and after 24 and 48 hours, the following clinical signs were evaluated: episodes of emesis and diarrhea, weight, hydration, blood glucose level, abdominal pain, and blood count. One control group animal died within the first hours of hospitalization. Both animals in the experimental group presented faster resolution of diarrheal episodes and shorter hospitalization time when compared to the surviving animal that received only supportive treatment. Although further studies are needed, ozone therapy showed promising results for the treatment of canine parvovirus.

Soroprevalência de anticorpos contra o vírus da cinomose canina, parvovírus e adenovírus em cães de um abrigo de animais brasileiro

ABSTRACT This study aimed to identify and compare the seroprevalence for canine distemper virus (CDV), canine parvovirus (CPV), and canine adenovirus (CAV) between newly admitted and already sheltered dogs. 122 dogs over six months of age and unvaccinated upon admission were sampled and divided into two groups: (A) newly admitted dogs and (B) dogs sheltered for at least two months. Sera were collected to determine IgG antibody titers against CDV, CPV, and CAV. We conducted a descriptive analysis of the samples and a chi-square test to investigate the relationship between potential elements associated with protective antibody titers. The results were: 56.5% of the dogs had protective levels of antibodies to all three pathogens. Dogs in group A had lower titers compared to those in group B for all three pathogens, with significant differences for CDV and CAV. We found no significant difference between the proportion of seropositive dogs and their age or reproductive status. The study suggests that the examined pathogens can circulate in the animal shelter and that dogs can be more exposed to these pathogens in the shelter than in the urban environment. Therefore, an effective immunization program should be carried out on all animals upon admission to shelters.

Canine parvovirus 2 detection using a LSPR biosensing method with gold nanoparticles

A new, fast and inexpensive promising AuNP protocol based on antibody deposition to detect canine parvovirus 2 from stool samples.

Canine parvo viral enteritis in dogs: Diagnostic and therapeutic evaluation

A total of 110 dogs presented to Teaching Veterinary Clinical Complex, CSKHPKV, Palampur (H.P.), India with the history of enteritis/gastroenteritis were screened for Canine Parvovirus (CPV). Out of these 110 dogs, 48 dogs were found positive for CPV by using Scanvet - a rapid antigen detection kit. All the 110 samples were subjected to Polymerase Chain Reaction (PCR) to check whether there were some cases that were false positive or false negative by Scanvet. Positive cases were, then, divided into 4 groups of 12 dogs each, with 4 different treatment regimens followed for each group. In addition to standard treatment protocol, our study tested effect of immunomodulators (Vitamin E &amp; Selenium) and antiviral “Oseltamivir” on recovery of dogs. This type of study (using Oseltamivir and immunomodulators) was not done previously in the state and hence, our aim was to test whether this treatment increases survivability and recovery rate for dogs with Parvoviral enteritis in Himachal Pradesh. Groups containing immunomodulators were more efficacious than their counterparts without immunomodulators. Addition of Oseltamivir and immunomodulators to standard therapy resulted in reduced mortality, cessation of diarrhoea and vomiting earlier than routine therapy. Scanvet diagnostic kit was found to be a quick alternate method for diagnosis of Parvo Viral Enteritis. Overall, the group treated with antibiotic+ supportive+ symptomatic+ antiviral treatment along with immunomodulator displayed promising results.

Caracterização molecular de cepas de protoparvovírus carnívoros circulantes em gatos na Turquia

ABSTRACT: Cats are susceptible to feline panleukopenia virus (FPV) and canine parvovirus type 2 (CPV-2). Therefore, coinfection and superinfection with multiple parvovirus strains may occur, resulting in high heterogeneity and recombination. Considering the importance of cats as a potential source of genetic diversity for parvoviruses, we investigated the frequency of parvovirus infection in cats using their blood and fecal samples and performed molecular characterization of parvovirus strains circulating in cat populations. Accordingly, the fecal and blood samples of 60 cats with gastroenteritis symptoms were collected from Turkey’s Burdur, Isparta, and Izmit provinces. Of these 15 fecal samples tested as parvovirus-positive by PCR, 14 were confirmed to have been infected with true FPV strains by sequencing analysis. Through the phylogeny analysis, those were located in the FPV cluster, closely related to CPV-2, and one was discriminated in the CPV-2b cluster. Additionally, sequence analysis of the VP2 gene of CPV and FPV revealed that the FPV strains detected in Turkey and the vaccine strains were highly related to each other, with a nucleotide identity of 97.7- 100%. Furthermore, 13 variable positions were detected in VP2 of the field and reference FPV strains. Three synonymous mutations were determined in the VP2 gene. Some amino acid mutations in the VP2 protein-affected sites were considered responsible for the virus’s biological and antigenic properties. The partial sequence analysis of the VP2 gene revealed that four FPV strains detected in Turkey have a single nucleotide change from T to G at the amino acid position 384 between the nucleotides 3939-3941, which was reported for the first time. Therefore, these four isolates formed a different branch in the phylogenetic tree. The results suggest that both FPV and CPV-2b strains are circulating in domestic cats in Turkey and cats should be considered as potential sources of new parvovirus variants for cats, dogs and other animals.

Phylogenetic analysis of canine parvovirus isolates from west Mediterranean region of Türkiye.

Canine parvovirus type 2 (CPV-2) causes hemorrhagic enteritis, and is one of the most important and contagious pathogens of dogs. In this study, we aimed to determine the prevalence and antigenic variants of CPV enteritis in dogs. Fecal samples were collected from 35 dogs with mucoid to hemorrhagic diarrhea in the Western Mediterranean region of Türkiye between October 2019 and March 2021. DNA was isolated from the samples and examined using PCR analysis. Twenty-eight out of 35 dogs (80.00%) were detected to be positive for CPV. Of these, three had already been vaccinated. The partial VP2 genes of 15 CPV positive samples producing strong bands in agarose gels were sequenced. All strains were identified as CPV-2b, and the amino acid changes were identified. Discriminative amino acid changes were detected for different amino acid positions clearly defining new CPV-2b variants. Of the 15 isolates, three had previously unreported synonymous mutations. Phylogenetic analysis indicated that the strains obtained in this study were closely related to isolates from the Mersin province of Türkiye, except for three isolates that had synonymous mutations and were located in a separate branch from the other CPV-2b genetic variants previously detected in Mersin Province and Urfa Province in Türkiye. This study demonstrates the increase in the prevalence rates for CPV-2b circulating in vaccinated and nonvaccinated dogs. Taking into account the data from phylogenetic trees which highlights differences between the vaccine strains and the isolates, re-designing immunization strategies needs necessary.

Emergence of a novel canine parvovirus 2c strain in India

Emergence of a novel canine parvovirus 2c strain in India

Molecular Characterization and Phylogenetic Analysis of Canine Parvovirus Isolates in Palestine

Molecular Characterization and Phylogenetic Analysis of Canine Parvovirus Isolates in Palestine

CPV Tahmininde Makine Öğrenme Yöntemlerinin Performanslarının Değerlendirilmesi: Farklı Bölgeler ve Parametreler ile Büyük Veri Uygulaması

Scopa: In the project, machine learning methods that can interpret health data have been applied specifically to Canine parvovirus infection. While CPV can be diagnosed based on clinical findings, it needs to be supported by laboratory findings to distinguish it from other infections. Correct diagnosis is vital to distinguish CPV from other infections with bloody diarrhoea, which can result in death in puppies. For this reason, by analysing the virus together with other data that may be affected by the virus, the methods of making the most accurate decision were compared and evaluated. Purpose: In this study, it was aimed to interpret CPV, which is considered to be one of the most important infectious agents of dogs, popularly known as mad-head disease, using K-NearestNeighbour (KNN), RandomForest (RF), Logistic Regression and NaiveBayes classification algorithms in terms of different parameters. When the total accuracy values were examined, the accuracy rates decreased in logistic regression and RF methods when the insignificant variable was removed in the model. Result: RF method made the best predictions when Platelets, Platelet (PLT) variable was in the model.In cases where we do not want to remove this variable from the model, it can give us very efficient results. KNN method gives better results when the number of variables decreases. Especially when the data size increases, it has been observed that the machine learning method gives more efficient results with better performance. Keywords: Big Data, Data Mining, Big Data in Health, Prediction Algorithms, Canine parvovirus (CPV)

Transition of dominant canine parvovirus genotype from 2b to 2c in Vietnamese dogs.

Canine parvovirus (CPV) is one of the most important pathogens causing enteritis in dogs. Although there have been a few reports of CPV in Vietnam, recent information on CPV infection in domestic dogs in Vietnam is limited. Faecal samples collected from 30 diarrheic and 50 healthy dogs were examined by PCR for detection of CPV DNA. The prevalence of CPV in diarrheic dogs (43.3%, 13/30) was significantly higher than in healthy dogs (4.0%, 2/50), indicating that CPV was a major cause of diarrhoea in domestic dogs. Genotyping of 15 CPV strains showed that both CPV‑2a and CPV‑2c were circulating and that CPV‑2c was a dominant CPV variant in Vietnam. Virus isolation was performed from faecal samples using A72/cSLAM cells, and nine CPV strains were successfully isolated. The dominant genotype spreading among Vietnamese dogs has changed from CPV‑2b to CPV‑2c.

Molecular characterization and antiviral effects of canine interferon regulatory factor 1 (CaIRF1)

BackgroundInterferon regulatory factor 1 (IRF1) is an important transcription factor that activates the type I interferon (IFN-I) response and plays a vital role in the antiviral immune response. Although IRF1 has been identified in several mammals, little information related to its function in canines has been described.ResultsIn this study, canine IRF1 (CaIRF1) was cloned. After a series of bioinformatics analyses, we found that the CaIRF1 protein structure was similar to that of other animal IRF1 proteins, including a conserved DNA-binding domain (DBD), an IRF-association domain 2 (IAD2) domain and two nuclear localization signals (NLSs). An indirect immunofluorescence assay (IFA) revealed that CaIRF1 was mainly distributed in the nucleus. Overexpression of CaIRF1 in Madin-Darby canine kidney cells (MDCK) induced high levels of interferon β (IFNβ) and IFN-stimulated response element (ISRE) promoter activation and induced interferon-stimulated gene (ISG) expression. Subsequently, we assayed the antiviral activity of CaIRF1 against vesicular stomatitis virus (VSV) and canine parvovirus type-2 (CPV-2) in MDCK cells. Overexpression of CaIRF1 effectively inhibited the viral yields of VSV and CPV-2, while knocking down of CaIRF1 expression mildly increased viral gene copies.ConclusionsCaIRF1 is involved in the cellular IFN-I signaling pathway and plays an important role in the antiviral response.

The Mechanism of Important Components in Canine Fecal Microbiota Transplantation.

Fecal microbiota transplantation (FMT) is a potential treatment for many intestinal diseases. In dogs, FMT has been shown to have positive regulation effects in treating Clostridioides difficile infection (CDI), inflammatory bowel disease (IBD), canine parvovirus (CPV) enteritis, acute diarrhea (AD), and acute hemorrhagic diarrhea syndrome (AHDS). FMT involves transplanting the functional components of a donor's feces into the gastrointestinal tract of the recipient. The effective components of FMT not only include commensal bacteria, but also include viruses, fungi, bacterial metabolites, and immunoglobulin A (IgA) from the donor feces. By affecting microbiota and regulating host immunity, these components can help the recipient to restore their microbial community, improve their intestinal barrier, and induce anti-inflammation in their intestines, thereby affecting the development of diseases. In addition to the above components, mucin proteins and intestinal epithelial cells (IECs) may be functional ingredients in FMT as well. In addition to the abovementioned indications, FMT is also thought to be useful in treating some other diseases in dogs. Consequently, when preparing FMT fecal material, it is important to preserve the functional components involved. Meanwhile, appropriate fecal material delivery methods should be chosen according to the mechanisms these components act by in FMT.

Hyperkeratotic erythema multiforme variant in 17 dogs.

A new canine subgroup defined as 'old-dog' or 'hyperkeratotic' erythema multiforme (HKEM) with marked hyperkeratosis and parakeratosis has been proposed without any detailed description of larger case series. We report herein the signalment, clinical signs, treatment outcome, and histopathological and immunological findings in 17 dogs with HKEM. Inclusion criteria were the presence of (i) scaly skin lesions with or without crusting; and (ii) microscopic lesions typical of EM (i.e. a panepidermal cytotoxic lymphocytic dermatitis with or without basal keratinocyte apoptosis); and (iii) microscopic ortho- and/or parakeratotic hyperkeratosis affecting the interfollicular epidermis. Clinical questionnaires and skin biopsies were reviewed. Polymerase chain reactions for epidermotropic viruses and direct immunofluorescence were performed. Various breeds were affected with an over-representation of males in their mid-to-late adulthood (median age 9 years). Generalised skin lesions included multifocal-to-coalescing, linear and annular macules and plaques with erythema and adherent firm crusting. Microscopic lesions were specific for EM and featured prominent superficial epidermal apoptosis with lymphocytic satellitosis and parakeratosis. No drug triggers were identified. Polymerase chain reactions for canine herpesvirus polymerase gene, canine parvovirus and canine distemper virus were negative in all HKEM and canine erosive EM (15 dogs) biopsies. Lesions failed to respond to oral and/or topical antimicrobials. Complete remission of signs was achieved in 9 of 17 dogs (53%) using immunosuppressive regimens. Hyperkeratotic erythema multiforme (HKEM) is a chronic, persistent and clinically distinctive erythema multiforme (EM) variant that differs from 'classic' vesiculobullous erosive-to-ulcerative EM in dogs.

G2/M checkpoint regulation and apoptosis facilitate the nuclear egress of parvoviral capsids.

The nuclear export factor CRM1-mediated pathway is known to be important for the nuclear egress of progeny parvovirus capsids in the host cells with virus-mediated cell cycle arrest at G2/M. However, it is still unclear whether this is the only pathway by which capsids exit the nucleus. Our studies show that the nuclear egress of DNA-containing full canine parvovirus. capsids was reduced but not fully inhibited when CRM1-mediated nuclear export was prevented by leptomycin B. This suggests that canine parvovirus capsids might use additional routes for nuclear escape. This hypothesis was further supported by our findings that nuclear envelope (NE) permeability was increased at the late stages of infection. Inhibitors of cell cycle regulatory protein cyclin-dependent kinase 1 (Cdk1) and pro-apoptotic caspase 3 prevented the NE leakage. The change in NE permeability could be explained by the regulation of the G2/M checkpoint which is accompanied by early mitotic and apoptotic events. The model of G2/M checkpoint activation was supported by infection-induced nuclear accumulation of cyclin B1 and Cdk1. Both NE permeability and nuclear egress of capsids were reduced by the inhibition of Cdk1. Additional proof of checkpoint function regulation and promotion of apoptotic events was the nucleocytoplasmic redistribution of nuclear transport factors, importins, and Ran, in late infection. Consistent with our findings, post-translational histone acetylation that promotes the regulation of several genes related to cell cycle transition and arrest was detected. In conclusion, the model we propose implies that parvoviral capsid egress partially depends on infection-induced G2/M checkpoint regulation involving early mitotic and apoptotic events.

Tracing the Genetic Evolution of Canine Parvovirus Type 2 (CPV-2) in Thailand.

Canine parvovirus type 2 (CPV-2) is responsible for hemorrhagic gastroenteritis in dogs worldwide. High genomic substitution rates in CPV-2 contribute to the progressive emergence of novel variants with increased ability to evade the host immune response. Three studies have analyzed the genomic mutations of CPV-2 variants in Thailand. These investigations were independently conducted at different timepoints. Thus, a retrospective integrated analysis of CPV-2 genomic mutations has not been fully performed. Our study aimed at evaluating the evolutionary changes in CPV-2 in Thailand from 2003 to 2019. Two hundred and sixty-eight Thai CPV-2 nucleotide sequences were used for multiple amino acid sequence alignment and phylogenetic analyses. From 2003 to 2010, CPV-2a and -2b were the only variants detected. CPV-2c, emerged in 2014, replacing CPV-2a and -2b, and has become a major variant in 2019. Phylogenetic analysis revealed that the proposed mutation pattern of VP2 amino acid residues could help distinguish Thai CPV-2 variants. This comprehensive examination provides insight into the genomic evolution of CPV-2 in Thailand since its first reporting in 2003, which may facilitate the surveillance of the potential genetic alteration of emergent CPV-2 variants.

A point-of-care dot blot ELISA assay for detection of protective antibody against canine adenovirus, canine parvovirus, and canine distemper virus is diagnostically accurate.

To determine diagnostic accuracy of a point-of-care antibody-screening test by determining sensitivity, specificity, and overall accuracy when compared to reference standard tests for antibody against core vaccine viruses canine adenovirus (CAV), canine parvovirus (CPV), and canine distemper virus (CDV). A further aim was to provide the practitioner with information to guide selection of vaccinal antibody testing methods. Canine sera from across North America were submitted to a fee-for-service titer-testing laboratory. Samples came from healthy pet dogs with known core vaccination history (n = 431) as well as unvaccinated dogs held in isolation (132). This study examined a total of 563 samples for CDV/CPV and 183 for CAV. Serum virus neutralization assays determined antibody titers for CDV and CAV. Hemagglutination inhibition assay determined antibody titers against CPV. All sera were also tested by point-of-care dot blot ELISA (index test). For all 3 viral antigens, the index test provided sensitivity ranging from 96.03% to 96.75% and specificity ranging from 87.50% to 94.33%. Overall accuracy ranged from 93.43% to 95.91%. The index test correlates well with reference standard tests and is a reliable, rapid screening test for detection of protective vaccinal antibody against CAV, CDV, and CPV in healthy dogs over 20 weeks of age. An accurate assessment of immunity allows clinicians to administer core vaccines appropriately as needed, avoiding unnecessary risk of adverse vaccine events.