Dogs In Korea Research Articles

Grain-free diet-induced dilated cardiomyopathy with atrial fibrillation in a Labrador Retriever: a case report

We describe the first reported case of grain-free diet-induced dilated cardiomyopathy (DCM) in a dog in Korea. An 11-year-old female dog was referred with abdominal distention, anorexia, and vomiting, having been fed a grain-free diet for > 5 years. Thoracic radiography revealed cardiomegaly and pulmonary edema. Atrial fibrillation was detected using electrocardiography. The dog was tentatively diagnosed with congestive heart failure (CHF) secondary to grain-free diet-induced DCM, and its diet changed to contain grain. Digoxin and diltiazem were prescribed for the atrial fibrillation, and pimobendan, enalapril, and furosemide for CHF. Significant improvements in echocardiographic indices were confirmed after 3 months.

Evaluation of hemagglutination inhibition test for canine respiratory coronavirus antibodies and seroprevalence in Korean dogs

Canine respiratory coronavirus (CRCoV) is a significant pathogen that causes respiratory diseases in dogs, collectively known as a canine infectious respiratory disease. The virus is highly contagious and exhibits high seroprevalence worldwide. Currently, bovine coronavirus (BCoV) enzyme-linked immunosorbent assay (ELISA) kits are used to detect CRCoV antibodies. However, BCoV-ELISA kits cannot differentiate between infections caused by BCoV and those caused by CRCoV. In this study, we evaluated the hemagglutination inhibition (HI) test for CRCoV by comparing it with the virus neutralization (VN) test. Subsequently, we evaluated the seroprevalence of CRCoV in 383 dog serum samples collected from South Korea utilizing the HI test. The HI test for CRCoV showed a strong correlation with the VN test (R = 0.83, p < 0.001). The analysis of seroprevalence revealed that 52.2% (95% confidence interval [CI], 47.2%–57.1%) of the Korean dog serum samples were positive. The seroprevalence exhibited varied with age, with a positivity rate of 43.9% in dogs under 1 year of age and 66.7% in dogs aged 3 to 5 years (odds ratio [OR], 2.54; 95% CI, 1.43–4.59). In conclusion, the HI test to monitor CRCoV antibody proved to be closely related to the VN test. Furthermore, over half of the dogs in Korea tested positive for CRCoV antibodies. These findings contribute to a better understanding of the sero-epidemiology of CRCoV.

Lymphadenopathy Associated with Disseminated Aspergillosis in a Jindo Dog in Korea

Lymphadenopathy Associated with Disseminated Aspergillosis in a Jindo Dog in Korea

Molecular analysis of Rickettsia spp. and related tick-borne pathogens detected in dogs in Korea

Ticks are widespread in nature and serve as primary vectors for several tick-borne pathogens (TBPs). Ticks and TBPs cause considerable harm to humans and animals and have emerged as a major global public health concern. Domestic dogs are the major reservoirs of zoonotic agents owing to their constant interaction with humans. This study aimed to assess the prevalence and risk factors of canine TBPs, such as Rickettsiales, Coxiella burnetii, hepatozoa, and Borrelia spp., using molecular analyses. A total of 906 dogs were examined and 4 TBPs were identified: Anaplasma phagocytophilum (5; 0.6%), Hepatozoon canis (9; 1.0%), Candidatus Rickettsia longicornii (2; 0.2%), and Rickettsia tamurae (1; 0.1%). Ehrlichia spp., C. burnetii, and Borrelia spp. were not detected. To the best of our knowledge, this is the first study to perform a phylogenetic analysis of Candidatus R. longicornii and R. tamurae in dogs. These findings can help determine the potential public health risks by enhancing our understanding of the geographical and vector distributions of TBPs in Korea.

인도적 들개 포획 방법 및 도구의 활용

Feral dogs are not friendly to people and are very difficult to capture, unlike stray dogs in Korea. In addition, various problems caused by feral dogs are on the rise, so capture and adoption are urgently needed, but it is difficult to capture. The use of the COLLARUM® Canine Capture Device is considered to be a very useful live capture tool in the domestic situation where it is difficult to capture feral dogs. This capture tool meets international humanitarian capture standards and is already widely used in Australia and other places where feral dogs cause ecological problems, so its effectiveness and safety have been verified. It is easy to install and move, so it is possible to install many of them in places where it is difficult to use a capture frame, such as a mountain area, which is the main wild dog habitat in Korea. As described above, COLLARUM® can be installed in almost any place, including mountainous areas, so it is possible to safely capture feral dogs as well as stray dogs, enabling effective management of abandoned animals. Therefore, it is considered to be the equipment that should be most actively considered for domestic introduction and local government distribution in order to manage the population of wild dogs and increase the capture rate.

Bacterial Prevalence in Skin, Urine, Diarrheal Stool, and Respiratory Samples from Dogs.

The emergence of bacterial infections in companion animals is a growing concern as humans can also be infected through the transmission of pathogenic bacteria. Because there have been few studies conducted on companion animals, the extent and significance of prevalence in veterinary practices remain unknown. This is the first nationwide surveillance report aimed at elucidating the prevalence pattern and associated infections of isolated bacteria from dogs in Korea. Bacterial isolates were collected from seven different laboratories participating in the Korean Veterinary Antimicrobial Resistance Monitoring System from 2018 to 2019. The samples were obtained from the diarrheal stool, skin/ear, urine, and respiratory samples of veterinary hospital-visited dogs. Isolation and identification of bacterial species was carried out using a bacterial culture approach and then confirmed with matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF) and polymerase chain reaction (PCR). Out of 3135 isolates in dogs, 1085, 1761, 171, and 118 were extracted from diarrheal stool, skin/ear, urine, and respiratory samples, respectively. The overall prevalence of bacteria was higher among two age groups (1–5 and 6–10 years) with a 66.5 percent prevalence. This study showed that Escherichia coli was the most prevalent species among isolated bacterial species of diarrheal and urine origin, whereas Staphylococcus pseudintermedius was the most prevalent among skin and respiratory sample isolates. The data on the prevalence of bacteria for each dog specimen could provide basic information to estimate the extent of bacterial infection and antimicrobial resistance development and to guide veterinarians in therapeutic decisions in clinical practices throughout Korea.

Molecular Detection and Genetic Diversity of Blastocystis in Korean Dogs.

Blastocystis is a genus of unicellular heterokont parasites belonging to a group of organisms known as Stramenopiles, which includes algae, diatoms, and water molds. Blastocystis includes several species that habitat in the gastrointestinal tracts of organisms as diverse as humans, farm animals, birds, rodents, reptiles, amphibians, fish, and cockroaches. It is important to public health and distributed globally, but its prevalence in dogs in Korea has not been reported to date. Here, we collected 787 canine fecal samples and assessed Blastocystis infection by age, sex, region, season, and diarrhea symptoms. We determined Blastocystis subtypes using phylogenetic analyses based on 18S rRNA gene sequences. We identified, 10 Blastocystis positive samples (1.3%). A higher proportion of infected dogs was asymptomatic; however, infection rates did not significantly differ according to region, age, sex, and season. Phylogenetic analysis showed that the Blastocystis sp. identified belonged to 4 subtypes (STs), ST1, ST5, ST10, and ST14, thus revealed the genetic diversity of Blastocystis sp. in dogs Korean. This is first report on the presence of Blastocystis sp. in dogs Korean. This study revealed a lower infection rate than expected and differed from previous studies in STs. Further studies are warranted to observe the national infection status of Blastocystis in dogs and the genetic characteristics of this genus.

Splenic smooth muscle tumors in 7 dogs: case reports

We describe 7 cases of splenic smooth muscle tumors in dogs. Histopathological and immunohistochemical analysis revealed that 6 cases were diagnosed as splenic leiomyosarcoma and 1 case as leiomyoma. All dogs underwent splenectomy without chemotherapy, and one of them was euthanized 2 months after surgery because of hepatic metastasis. Of the remaining 6 dogs, 5 died in the postoperative period and only one dog survived > 4 years. The median survival of the 6 dogs was 16.9 months. To the best of our knowledge, this is the first detailed study on splenic smooth muscle tumors in dogs in Korea.

Clinical features and management of snake bites in 70 dogs in Korea.

Snakebites remain a devastating and life-threatening environmental hazard. While the management of snakebites has been well described in humans, few clinical data and guidelines exist for dogs, especially in Korea. This retrospective study evaluated the clinical features of 70 dogs with snakebite wounds in Korea. The medical records of 72 dogs that presented to three animal hospitals from June 2008 to July 2021 were reviewed; among these, 70 dogs that met the inclusion criteria were enrolled. Their signalment, history, clinical signs, physical examination, blood analysis, treatment, and prognosis were also evaluated. Of 70 dog owners, 35 (50%) witnessed the bite, with a mean time between bite and hospital presentation of 9.7 ± 4.1 h in 58 dogs. Blood smears were evaluated in 45 dogs, of which 28 (62%) showed echinocytosis. Anemia and acute kidney injury were found in 21 (29%) and 2 dogs (3%), respectively. A total of 37 dogs (53%) were hospitalized, 5 (7%) of which died. The most significant finding was the high prevalence of echinocytosis. The data from this retrospective study could inform the management of dogs bitten by snakes in Korea.

PAR-006 - Characterization of NDM-5-producing Escherichia coli isolates from dogs in Korea

PAR-006 - Characterization of NDM-5-producing Escherichia coli isolates from dogs in Korea

Comparative genomics of canine Lactobacillus reuteri reveals adaptation to a shared environment with humans.

Lactobacillus reuteri is a gram-positive, non-motile bacterial species that has been used as a representative microorganism model to describe the ecology and evolution of vertebrate gut symbionts. Because the genetic features and evolutionary strategies of L. reuteri from the gastrointestinal tract of canines remain unknown, we tried to construct draft genome canine L. reuteri and investigate modified, acquired, or lost genetic features that have facilitated the evolution and adaptation of strains to specific environmental niches by this study. To examine canine L. reuteri, we sequenced an L. reuteri strain isolated from a dog in Korea. A comparative genomic approach was used to assess genetic diversity and gain insight into the distinguishing features related to different hosts based on 27 published genomic sequences. The pan-genome of 28 L. reuteri strains contained 7,369 gene families, and the core genome contained 1070 gene families. The ANI tree based on the core genes in the canine L. reuteri strain (C1) was very close to those for three strains (IRT, DSM20016, JCM1112) from humans. Evolutionarily, these four strains formed one clade, which we regarded as C1-clade in this study. We could investigate a total of 32,050 amino acid substitutions among the 28 L. reuteri strain genomes. In this comparison, 283 amino acid substitutions were specific to strain C1 and four strains in C1-clade shared most of these 283 C1-strain specific amino acid substitutions, suggesting strongly similar selective pressure. In accessory genes, we could identify 127 C1-clade host-specific genes and found that several genes were closely related to replication, recombination, and repair. This study provides new insights into the adaptation of L. reuteri to the canine intestinal habitat, and suggests that the genome of L. reuteri from canines is closely associated with their living and shared environment with humans.

Genetic characterization of canine parvovirus type 2c from domestic dogs in Korea.

Canine parvovirus type 2 (CPV‐2) is an aetiological agent that causes acute haemorrhagic enteritis and fatal myocarditis in dogs. Since CPV‐2 first emerged in the late 1970s, its rapid evolution has resulted in three antigenic variants: CPV‐2a, CPV‐2b and CPV‐2c. Here, we report, for the first time in Korea, two cases of CPV‐2c infection in two dogs with severe diarrhoea. The complete open reading frame (4,269nt) of CPV‐2, encoding both non‐structural (NS) and structural (VP) proteins, was sequenced. Based on the amino acid Gln present at residue 426 of the VP2 gene, these strains were typed as CPV‐2c, and were named Korea CPV‐2c_1 and Korea CPV‐2c_2. These strains shared 99.48% reciprocal nucleotide sequence identity and had the highest nucleotide identity (99.77%–99.34%) with Asian CPV strains isolated in China, Italy (found in a dog imported from Thailand), and Vietnam from 2013 to 2017. Phylogenetic analysis based on the non‐structural (NS1) and capsid (VP2) genes revealed that Korean CPV‐2c strains clustered closely to Asian CPV strains, and separately from strains isolated in Europe, South America and North America. Amino acid changes never reported before were observed in NS1 (Thr70Pro, Cys287Tyr), VP1 (Lys17Arg, Phe33Leu) and VP2 (Gln365His, Ala516Val). Additional observed mutations, including Phe267Tyr, Tyr324Ile and Gln370Arg, have been previously reported in the recent CPV‐2c strains with Asian origins. These results suggest that the Korean CPV‐2c strains were potentially introduced via neighbouring Asian countries.

Identification of fusidic acid resistance in clinical isolates of Staphylococcus pseudintermedius from dogs in Korea.

Staphylococcus pseudintermedius is a major bacterial species associated with canine pyoderma and otitis. Fusidic acid is used to treat skin infections caused by Gram-positive bacteria. The incidence of resistance to fusidic acid in S.pseudintermedius has importance in terms of limiting treatment options for bacterial infections. To evaluate the occurrence and mechanisms of fusidic acid resistance in clinical isolates of S.pseudintermedius. Fifty-two S.pseudintermedius isolates were collected from dogs with pyoderma (n=36) or otitis (n=16). The disk diffusion method determined that isolates <24mm were resistant to fusidic acid. Minimum inhibitory concentrations (MICs) were measured by the E-test in those with confirmed resistance to fusidic acid by the disk diffusion method. Phenotypically fusidic acid resistant isolates were subjected to PCR to detect the presence of resistance-related genes (fusA, fusB, fusC and fusD) and fusA was further sequenced to identify point mutations. Fourteen of 52 (27%) S.pseudintermedius isolates were resistant to fusidic acid and all of these showed low-level resistance. Among fusidic acid resistant isolates, fusA point mutations were confirmed in 11 isolates and amino acid substitutions were found in five. fusC was detected in seven isolates, but neither fusB nor fusD was detected. This study demonstrates the occurrence and resistance mechanisms to fusidic acid in clinical isolates of S.pseudintermedius. Continuous monitoring for fusidic acid resistance is recommended.

Molecular Detection and Characterization of Borrelia garinii (Spirochaetales: Borreliaceae) in Ixodes nipponensis (Ixodida: Ixodidae) Parasitizing a Dog in Korea

The present study aimed to detect and characterize Borrelia spp. in ticks attached to dogs in Korea. Overall, 562 ticks (276 pools) attached to dogs were collected and tested for Borrelia infection by PCR targeting the 5S-23S rRNA intergenic spacer region (rrf-rrl). One tick larva (pool level, 0.4%; individual level, 0.2%) was confirmed by sequencing Borrelia garinii, a zoonotic pathogen. For molecular characterization, the outer surface protein A (ospA) and flagellin genes were analyzed. Phylogenetic ospA analysis distinguished B. garinii from B. bavariensis, which has been recently identified as a novel Borrelia species. On the other hand, phylogenetic analysis showed that single gene analysis involving rrf-rrl or flagellin was not sufficient to differentiate B. garinii from B. bavariensis. In addition, the B. garinii-infected tick was identified as Ixodes nipponensis by sequencing according to mitochondrial 16S rRNA and the second transcribed spacer region. To our knowledge, this is the first study to report the molecular detection of B. garinii in I. nipponensis parasitizing a dog in Korea. Continuous monitoring of tick-borne pathogens in ticks attached to animals is required to avoid disease distribution and possible transmission to humans.

First detection of multiresistance pRE25-like elements from Enterococcus spp. in Staphylococcus pseudintermedius isolated from canine pyoderma

Enterococcus pRE25 is a conjugative and mobilising multiresistance plasmid from Enterococcus faecalis RE25. pRE25-like enterococcal plasmid pWZ909 mediates the delivery of vancomycin resistance to methicillin-resistant Staphylococcus aureus via a Tn1546-like transposon. However, whether pRE25-like elements contribute to multidrug resistance in Staphylococcus spp. has not yet been investigated. Here we describe the first detection of multiresistance pRE25-like elements in the chromosomal DNA of multidrug-resistant Staphylococcus pseudintermedius (MDRSP). A total of 46 MDRSP clinical strains were isolated from canine pyoderma in Korea. Their genetic characteristics were analysed by multilocus sequence typing (MLST) and PCR targeting pRE25-like elements. Whole-genome sequencing (WGS) was performed on four isolates. WGS detected that the chromosomal 22-kb pRE25-like elements contained five antimicrobial resistance genes [cat, erm(B), aphA-3, aadK and sat4], IS1252, IS256, and a toxin-antitoxin system within copies of IS1216. BLASTn alignment analysis revealed that 84% of the chromosomal 22-kb pRE25-like elements sequence is homologous (99.8% identity) to the enterococcal pRE25 plasmid sequence. PCR assay showed that 52.2% of MDRSP isolates were positive for pRE25-like elements and were presumed to contain pRE25-like elements (pRE25 group). The sequence types (STs) of the pRE25 group were diverse, with 18 STs identified, among which 12 STs were first reported in Korea. Enterococcal pRE25-like elements are suspected to be widespread in MDRSP isolated from companion dogs in Korea. Considering that companion dogs live in a closely shared environment with humans, continuous surveillance of pRE25-like elements is needed for other staphylococci commonly isolated from humans.

The degree of major histocompatibility complex matching between purebred Maltese and mongrel dogs using microsatellite markers.

Long-term maintenance of transplanted organs is one of the major factors that increases survival time of recipients. Although obtaining a major histocompatibility complex (MHC)-matched donor with the recipient is essential for successful organ transplantation, there have been limited reports on MHC matching between dogs. In this study, we analyzed the canine MHC matching rates using Maltese, one of the most popular purebred dogs, and mongrel dogs in Korea. Genomic DNA was extracted from blood leukocytes and DNA was amplified by polymerase chain reaction with primers specific to MHC microsatellite markers. The MHC matching degree was confirmed by the microsatellite markers using polyacrylamide gel electrophoresis. The MHC matching rates of each donor-recipient groups including Maltese-Maltese, mongrel-mongrel and Maltese-mongrel were 4.76%, 5.13% and 6.67%, respectively. There were no significant differences in the MHC matching degree between each group. These results demonstrate that MHC-matched donors could be selected from other breeds as much as from the same breed for transplantation. Knowledge of the MHC matching degree of purebred and mongrel dogs would offer valuable information not only for improving the success rate of organ transplantation surgery in canine patients but also for transplantation research using experimental canine models.

Isolation and identification of canine adenovirus type 2 from a naturally infected dog in Korea

Isolation and identification of canine adenovirus type 2 from a naturally infected dog in Korea

First Detection of New Delhi Metallo-β-Lactamase-5-ProducingEscherichia colifrom Companion Animals in Korea

The gene for New Delhi metallo-β-lactamase-5 (NDM-5) in Escherichia coli has been identified in many countries mainly from human clinical specimens. The isolates carrying this gene are even more rarely isolated from companion animals. In this study, four carbapenem-resistant isolates were recovered from four dogs in Korea. All isolates carried blaNDM-5 and exhibited resistance to meropenem and imipenem, and were susceptible to colistin. Epidemiological analysis showed that all four isolates were sequence type 410 (ST410) and shared 99% similarity as determined by pulsed-field gel electrophoresis analysis. Among the four isolates, the Z0117EC0033 strain was randomly selected for whole-genome sequencing, composed of a 4.7Mb circularized chromosome carrying the CMY-2 gene and two plasmids. The first plasmid of the IncFIB type had 83 coding sequences (CDS) in ca. 74 kb. The second smaller plasmid of the IncX3 type had 57 CDS and carried only the blaNDM-5 gene in ca. 46 kb. The plasmid structures were highly similar (> 99%) to those of the NDM-5 human-like IncX3 plasmid. This is the first report of carbapenemase-producing Enterobacteriaceae from companion animals in Korea. The human-like blaNDM-5 IncX3 plasmid identified in this study suggests a potential transmission route of the NDM-5 plasmid between humans and companion animals.

Prevalence of dog erythrocyte antigen 1, determined via immunochromatography, in domestic dogs in Korea

Prevalence of dog erythrocyte antigen 1, determined via immunochromatography, in domestic dogs in Korea

Ctenocephalides canis is the dominant flea species of dogs in the Republic of Korea

BackgroundThe status of flea infestation in dogs is an important public health concern because of their cosmopolitan distribution worldwide and the flea-borne disease transmission. In the present study, we investigated the flea infestation among 116 outdoor dogs (57 females and 59 males) in 8 rural areas of Jeonnam Province, Republic of Korea.ResultsThirty-three dogs (28.4%) were infested with fleas, and all dogs were infested with Ctenocephalides canis. One dog from Hampyeong was co-infested with Ctenocephalides felis orientis, but no dogs were infested with Ctenocephalides felis felis. The reasons behind this almost exclusive distribution of flea species in dogs from Korea are currently unknown and will require further epidemiological and biological investigations. However, since all dogs investigated in the study were raised in an outdoor environment, the development of flea eggs, larvae and pupae in climatic conditions in Korea might have negatively affected the survival of other flea species. Due to the shoes-off culture and floor-heating system of Korean houses, indoor dogs are rarely infested with fleas in Korea.ConclusionTo our knowledge, this is the first report on the distribution survey of flea species infesting dogs in Korea and the first report of C. orientis infesting a dog in Korea.