Safety and immunogenicity of a SARS-CoV-2 mRNA vaccine (SYS6006) in minks, cats, blue foxes, and raccoon dogs.

Minks, cats, and some other species of carnivores are susceptible of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and have a high risk of transmitting SARS-CoV-2 to humans. The development of animal vaccines can be an effective measure to protect animals against SARS-CoV-2 and reduce the potential risk of human infection. We previously developed a messenger ribonucleic acid (mRNA) vaccine SYS6006 that has been proven to be an efficient coronavirus disease 2019 (COVID-19) vaccine widely used in humans. Here, we further evaluated the safety and immunogenicity of SYS6006 as an animal COVID-19 vaccine candidate for SARS-CoV-2 susceptible animals or wild animals. SYS6006 was safe and immunogenic in mice and completely protected mice against mouse-adapted SARS-CoV-2 infection in the upper and lower respiratory tracts. SYS6006 was able to induce neutralizing antibodies against the SARS-CoV-2 wild-type, Delta, and Omicron BA.2 strain on day 7 after prime immunization, and two doses of immunization could enhance the neutralizing antibody responses and produce long-lasting potent antibodies for more than 8 months in minks and cats, blue foxes, and raccoon dogs, while all immunized animals had no abnormal clinical signs during immunization. These results provided here warrant further development of this safe and efficacious mRNA vaccine platform against animal COVID-19.

Farmed fur animals harbour viruses with zoonotic spillover potential.

Animals such as raccoon dogs, mink and muskrats are farmed for fur and are sometimes used as food or medicinal products1,2, yet they are also potential reservoirs of emerging pathogens3. Here we performed single-sample metatranscriptomic sequencing of internal tissues from 461 individual fur animals that were found dead due to disease. We characterized 125 virus species, including 36 that were novel and 39 at potentially high risk of cross-species transmission, including zoonotic spillover. Notably, we identified seven species of coronaviruses, expanding their known host range, and documented the cross-species transmission of a novel canine respiratory coronavirus to raccoon dogs and of bat HKU5-like coronaviruses to mink, present at a high abundance in lung tissues. Three subtypes of influenza A virus-H1N2, H5N6 and H6N2-were detected in the lungs of guinea pig, mink and muskrat, respectively. Multiple known zoonotic viruses, such as Japanese encephalitis virus and mammalian orthoreovirus4,5, were detected in guinea pigs. Raccoon dogs and mink carried the highest number of potentially high-risk viruses, while viruses from the Coronaviridae, Paramyxoviridae and Sedoreoviridae families commonly infected multiple hosts. These data also reveal potential virus transmission between farmed animals and wild animals, and from humans to farmed animals, indicating that fur farming represents an important transmission hub for viral zoonoses.

The reduction in relative brain size in the domesticated dog is not an evolutionary singularity among the canids.

Domestication has long been considered the most powerful evolutionary engine behind dramatic reductions in brain size in several taxa, and the dog (Canis familiaris) is considered as a typical example that shows a substantial decrease in brain size relative to its ancestor, the grey wolf (Canis lupus). However, to make the case for exceptional evolution of reduced brain size under domestication requires an interspecific approach in a phylogenetic context that can quantify the extent by which domestication reduces brain size in comparison to closely related non-domesticated species responding to different selection factors in the wild. Here, we used a phylogenetic method to identify evolutionary singularities to test if the domesticated dog stands out in terms of relative brain size from other species of canids. We found that the dog does not present unambiguous signature of evolutionary singularity with regard to its small brain size, as the results were sensitive to the considerations about the ancestral trait values upon domestication. However, we obtained strong evidence for the hibernating common raccoon dog (Nyctereutes procyonoides) being an evolutionary outlier for its brain size. Therefore, domestication is not necessarily an exceptional case concerning evolutionary reductions in brain size in an interspecific perspective.

The First Report of Tritrichomonas Foetus and Tetratrichomonas Buttreyi in Raccoon Dogs (Nyctereutes Procyonoides) in China.

BACKGROUND: In recent years, the trichomonosis in raccoon dogs in China had occurred frequently. Pentatrichomonas hominis had been described in raccoon dogs in China in some previous studies. PURPOSE TO REVEAL: whether raccoon dogs can be infected by other trichomonad species besides P. hominis, and clarify the prevalence and species distribution of trichomonad in raccoon dogs. METHODS: Herein, the 389 fecal samples were collected from farm-raised raccoon dogs in Hebei Province, all the samples were detected using the microscopic examination and several fecal samples containing trichomonad-like organisms were processed, cultured, stained, and photographed. Meanwhile, all the samples were screened by the species-specific nested PCR based on the small subunit rRNA (SSU rRNA) gene of P. hominis,Tritrichomonas foetus and Tetratrichomonas buttreyi, respectively, and all positive secondary PCR amplications obtained in this study were sequenced, aligned and analysed. RESULTS: 62 fecal samples (15.9%,62/389) were trichomonad-positive under light microscopy, and the trichomonad-like cells were clearly observed in the culture contents. The PCR results showed that 100 samples were trichomonad-positive, including 45 P. hominis-positive samples (11.6%,45/389), 32 T. foetus-positive samples (8.2%,32/389), and 33 T. buttreyi-positive samples (8.5%,33/389), respectively. Double mixed infections were observed in 10 samples. The prevalence of T. foetus and P. hominis were both significantly higher in raccoon dogs with diarrhea (13.9%, and 25.0%) than that in raccoon dogs without diarrhea (7.6%, and 9.3%) (p < 0.05).All samples confirmed as trichomonad-positive under microscopy were also found to be trichomonad-positive by PCR analysis. The sequencing and phylogenetic analysis demonstrated the sequences obtained in this study belonged to P. hominis, T. foetus and T. buttreyi SSU rRNA, respectively. Among them, the T. buttreyi SSU rRNA sequences obtained in this study harbored the new sequence polymorphisms. Based on preliminary morphological and molecular analyses, raccoon dogs are considered as the new host of T. foetus and T. buttreyi. CONCLUSION: This is the first report about the identifcation and prevalence of T. foetus and T. buttreyi in raccoon dogs in China, and the results increase our knowledge about the host range and prevalence of trichomonad species.

Structural basis for raccoon dog receptor recognition by SARS-CoV-2.

Since the COVID-19 outbreak, raccoon dogs have been suggested as a potential intermediary in transmitting SARS-CoV-2 to humans. To understand their role in the COVID-19 pandemic and the species barrier for SARS-CoV-2 transmission to humans, we analyzed how their ACE2 protein interacts with SARS-CoV-2 spike protein. Biochemical data showed that raccoon dog ACE2 is an effective receptor for SARS-CoV-2 spike protein, though not as effective as human ACE2. Structural comparisons highlighted differences in the virus-binding residues of raccoon dog ACE2 compared to human ACE2 (L24Q, Y34H, E38D, T82M, R353K), explaining their varied effectiveness as receptors for SARS-CoV-2. These variations contribute to the species barrier that exists between raccoon dogs and humans regarding SARS-CoV-2 transmission. Identifying these barriers can help assess the susceptibility of other mammals to SARS-CoV-2. Our research underscores the potential of raccoon dogs as SARS-CoV-2 carriers and identifies molecular barriers that affect the virus's ability to jump between species.

Morphology of the aortic arch branching pattern in raccoon dogs (Nyctereutes procyonoides, Gray, 1834).

BACKGROUND: Aortic arch (AA) branching patterns vary among different mammalian species. Most previous studies have focused on dogs, whereas those on raccoon dogs remain unexplored. OBJECTIVES: The objective of this study was to describe the AA branching pattern in raccoon dogs and compare their morphological features with those of other carnivores. METHODS: We prepared silicone cast specimens from a total of 36 raccoon dog carcasses via retrograde injection through the abdominal aorta. The brachiocephalic trunk (BCT) branching patterns were classified based on the relationship between the left and right common carotid arteries. The subclavian artery (SB) branching pattern was examined based on the order of the four major branches: the vertebral artery (VT), costocervical trunk (CCT), superficial cervical artery (SC), and internal thoracic artery (IT). RESULTS: In most cases (88.6%), the BCT branched off from the left common carotid artery and terminated in the right common carotid and right subclavian arteries. In the remaining cases (11.4%), the BCT formed a bicarotid trunk. The SB exhibited various branching patterns, with 26 observed types. Based on the branching order of the four major branches, we identified the main branching pattern, in which the VT branched first (98.6%), the CCT branched second (81.9%), the SC branched third (62.5%), and the IT branched fourth (52.8%). CONCLUSIONS: The AA branching pattern in raccoon dogs exhibited various branching patterns with both similarities and differences compared to other carnivores.

Food Habits of Raccoon Dogs at An Agricultural Area in Shikoku, Western Japan.

The diet of raccoon dogs, which live in close proximity to agricultural fields in Matsuyama, western Japan, was studied throughout the year by the fecal analysis method (n = 114). Fruits were most important, accounting for 30-40% of the diet except in winter. Crops were next in importance, accounting for 10-30%. It was characteristic that the proportion of crops was greater and more stable than in other "satoyama" or rural areas in Japan. Crops included rice (Oryza sativa), wheat, sesame (Sesamum indicum), strawberries (Fragaria × ananassa), kiwi fruit (Actinidia chinensis var. deliciosa), ginkgo nuts (Ginkgo biloba), and persimmon (Diospyros kaki). Crops were important as the food for the raccoon dogs, but the use was not regarded as causing serious damage. Although wild boars (Sus scrofa), sika deer (Cervus nippon), and Japanese macaques (Macaca fuscata) were culled for pest control in the area, raccoon dogs were not culled. This may be a reason why the raccoon dog has coexisted with people in Japan.

Molecular epidemiology of Enterocytozoon bieneusi from foxes and raccoon dogs in the Henan and Hebei provinces in China.

BACKGROUND: Enterocytozoon bieneusi is a zoonotic pathogen widely distributed in animals and humans. It can cause diarrhea and even death in immunocompromised hosts. Approximately 800 internal transcribed spacer (ITS) genotypes have been identified in E. bieneusi. Farmed foxes and raccoon dogs are closely associated to humans and might be the reservoir of E. bieneusi which is known to have zoonotic potential. However, there are only a few studies about E. bieneusi genotype identification and epidemiological survey in foxes and raccoon dogs in Henan and Hebei province. Thus, the present study investigated the infection rates and genotypes of E. bieneusi in farmed foxes and raccoon dogs in the Henan and Hebei provinces. RESULT: A total of 704 and 884 fecal specimens were collected from foxes and raccoon dogs, respectively. Nested PCR was conducted based on ITS of ribosomal RNA (rRNA), and then multilocus sequence typing (MLST) was conducted to analyze the genotypes. The result showed that infection rates of E. bieneusi in foxes and raccoon dogs were 18.32% and 5.54%, respectively. Ten E. bieneusi genotypes with zoonotic potential (NCF2, NCF3, D, EbpC, CHN-DC1, SCF2, CHN-F1, Type IV, BEB4, and BEB6) were identified in foxes and raccoon dogs. Totally 178 ITS-positive DNA specimens were identified from foxes and raccoon dogs and these specimens were then subjected to MLST analysis. In the MLST analysis, 12, 2, 7 and 8 genotypes were identified in at the mini-/ micro-satellite loci MS1, MS3, MS4 and MS7, respectively. A total of 14 multilocus genotypes were generated using ClustalX 2.1 software. Overall, the present study evaluated the infection of E. bieneusi in foxes and raccoon dogs in the Henan and Hebei province, and investigated the zoonotic potential of the E. bieneusi in foxes and raccoon dogs. CONCLUSIONS: These findings expand the geographic distribution information of E. bieneusi' host in China and was helpful in preventing against the infection of E. bieneusi with zoonotic potential in foxes and raccoon dogs.

High-fat diet disrupts the gut microbiome, leading to inflammation, damage to tight junctions, and apoptosis and necrosis in Nyctereutes procyonoides intestines.

Given the burgeoning Nyctereutes procyonoides breeding industry and its growing scale, it is imperative to investigate the impact of high-fat diets on the health of these animals. This study involved 30 male Nyctereutes procyonoides of comparable weights (3 kg ±0.5), randomly assigned to either a control group or a high-fat diet group (n = 15 each). The latter group was fed a mixture of lard and basal diet in a 2:5 ratio, establishing a high-fat diet model in Nyctereutes procyonoides. This diet induced diarrhea and histopathological changes in the Nyctereutes procyonoides. Analysis of the small intestine contents using 16S rRNA sequencing revealed a high-fat diet-induced disruption in the gut microbiota. Specifically, Escherichia-Shigella emerged as the biomarker in the high-fat diet group (P = 0.049), while Vagococcus was prevalent in the control group (P = 0.049), indicating a significant increase in harmful bacteria in the high-fat diet group. Furthermore, this disrupted gut flora correlated with inflammation and oxidative stress, as evidenced by marked increases in TNF-α (P < 0.01), IL-1ß (P < 0.05), and IL-6 (P < 0.05) levels, measured via q-PCR, Western blot, and oxidative stress assays. In addition, q-PCR analysis revealed significant upregulation of apoptosis and necrosis markers, including Bax, Caspase3, Caspase9, Caspase12, RIPK3, and RIPK1 (P < 0.01 to P < 0.001), and a concurrent downregulation of the anti-apoptotic gene Bcl-2 (P < 0.01) in the high-fat diet group, consistent with protein expression trends. These findings suggest that a high-fat diet alters the gut microbiome toward a more harmful bacterial composition, escalating inflammatory responses and intestinal tissue permeability, culminating in intestinal cell apoptosis and necrosis.IMPORTANCEThis study examines the impact of high-fat diets on Nyctereutes procyonoides. Our research established a Nyctereutes procyonoides model on a high-fat diet, revealing significant health impacts, such as diarrhea, histological anomalies, and alterations in the gut microbiota. These findings emphasize the importance of preventing health issues and promoting sustainable industry growth. They highlight the significant impact of diet on gut microbiota and overall animal health.

Intravascular papillary endothelial hyperplasia in the lungs of a wild Korean raccoon dog.

A male Korean raccoon dog of unknown age was rescued and placed at the Daejeon Wildlife Rescue Center, Korea. Physical examination revealed severe emaciation and dehydration, as well as thick crusts and alopecia over most of the body. During medical care, the animal died and was submitted for postmortem examination. Firm, brown-red lesions of various sizes were observed on the surface of the lungs. In cross-sections of the lungs, pulmonary vessels were thickened and dilated, with white irregular papillary luminal projections. Histologically, pulmonary blood vessels were severely hyperplastic, characterized by thickened dilated walls and fibrous papillary projections covered with a single layer of endothelial cells (ECs). Hyperplastic fibrous connective tissue was confirmed by Masson trichrome staining. The ECs expressed CD31. We diagnosed the lesion as intravascular papillary endothelial hyperplasia, a unique non-neoplastic reactive process that has not been reported previously in pulmonary vessels of canids, equids, or felids, to our knowledge.

Prevalence of Pentatrichomonas hominis in foxes and raccoon dogs and changes in the gut microbiota of infected female foxes in the Hebei and Henan Provinces in China.

Pentatrichomonas hominis (P. hominis) is a zoonotic parasite that affects a wide range of hosts, causing gastrointestinal diseases. The present study aimed to evaluate the prevalence of P. hominis among caged foxes and raccoon dogs and the effect of P. hominis on the gut microbiota in female foxes. A total of 893 fresh fecal samples were collected from the Hebei and Henan Provinces in China. P. hominis was screened based on 18S rRNA gene expression via nested PCR. The difference in the gut microbiota between nine P. hominis-positive and nine P. hominis-negative samples was investigated by 16S rRNA gene sequencing. The total prevalence of P. hominis infection in foxes and raccoon dogs was 31.7% (283/893). The prevalence rates of P. hominis infection were 28.2% (88/312) and 33.6% (195/581) in foxes and raccoon dogs, respectively. Phylogenetic analysis revealed that all P. hominis strains detected in foxes and raccoon dogs in the present study were the zoonotic genotype CC1. Moreover, compared with those in the P. hominis-negative group, the diversity of the gut microbiota in the P. hominis-positive group was lower, and the abundance of Firmicutes and the ratio of Firmicutes/Bacteroidetes (F/B) in the P. hominis-positive group were lower than those in the P. hominis-negative group. We speculate that these differences may be due to indigestion and diarrhea in infected female foxes. Overall, the present study evaluated the prevalence of P. hominis in foxes and raccoon dogs in the Henan and Hebei Provinces and revealed that P. hominis infection interrupted the diversity of the gut microbiota in female foxes.

Multi-Omics Analysis Reveals the Pathogenesis of Growth-Disordered Raccoon Dog.

Microorganisms of the genus Eperythrozoon are a zoonotic chronic infectious disease with wide distribution. We found that raccoons infected with Eperythrozoon showed obvious stunting, which seriously affected the economic benefits of raccoon dogs. To investigate the pathogenesis of the raccoon dog, we used transcriptome and proteome sequencing to analyze the changes in mRNA, miRNA, and protein expression in raccoon dogs infected with Eperythrozoon and normal raccoons. The results showed that the expression levels of genes related to immunity, metabolism, and enzyme activity were significantly changed. Among these, ERLIN1, IGF1R, CREB3L1, TNS1, TENC1, and mTOR play key roles. Additionally, the miR-1268, miR-125b, miR-10-5p, and miR-10 as central miRNAs regulate the expression of these genes. Integrated transcriptomic and proteomic analyses revealed consistent trends in mRNA and protein changes in MYH9, FKBP1A, PRKCA, and CYP11B2. These results suggest that Eperythrozoon may contribute to the slow development of raccoons by affecting the expression of mRNAs and miRNAs, reducing their immunity and causing metabolic abnormalities.

Role of invasive carnivores (Procyon lotor and Nyctereutes procyonoides) in epidemiology of vector-borne pathogens: molecular survey from the Czech Republic.

BACKGROUND: Vector-borne pathogens (VBPs) are a major threat to humans, livestock and companion animals worldwide. The combined effect of climatic, socioeconomic and host composition changes favours the spread of the vectors, together with the expansion of invasive carnivores contributing to the spread of the pathogens. In Europe, the most widespread invasive species of carnivores are raccoons (Procyon lotor) and raccoon dogs (Nyctereutes procyonoides). This study focused on the detection of four major groups of VBPs namely Babesia, Hepatozoon, Anaplasma phagocytophilum and Bartonella in invasive and native carnivores in the Czech Republic, with the emphasis on the role of invasive carnivores in the eco-epidemiology of said VBPs. METHODS: Spleen samples of 84 carnivores of eight species (Canis aureus, Canis lupus, Lynx lynx, P. lotor, Martes foina, Lutra lutra, Mustela erminea and N. procyonoides) were screened by combined nested PCR and sequencing for the above-mentioned VBPs targeting 18S rRNA and cytB in hemoprotozoa, groEL in A. phagocytophilum, and using multilocus genotyping in Bartonella spp. The species determination is supported by phylogenetic analysis inferred by the maximum likelihood method. RESULTS: Out of 84 samples, 44% tested positive for at least one pathogen. Five different species of VBPs were detected in P. lotor, namely Bartonella canis, Hepatozoon canis, Hepatozoon martis, A. phagocytophilum and Bartonella sp. related to Bartonella washoensis. All C. lupus tested positive for H. canis and one for B. canis. Three VBPs (Hepatozoon silvestris, A. phagocytophilum and Bartonella taylorii) were detected in L. lynx for the first time. Babesia vulpes and yet undescribed species of Babesia, not previously detected in Europe, were found in N. procyonoides. CONCLUSIONS: Wild carnivores in the Czech Republic are hosts of several VBPs with potential veterinary and public health risks. Among the studied carnivore species, the invasive raccoon is the most competent host. Raccoons are the only species in our study where all the major groups of studied pathogens were detected. None of the detected pathogen species were previously detected in these carnivores in North America, suggesting that raccoons adapted to local VBPs rather than introduced new ones. Babesia vulpes and one new, probably imported species of Babesia, were found in raccoon dogs.

Detection and Genetic Characterization of Astroviruses in Brain Tissues of Wild Raccoon Dogs.

Astroviruses (AstVs) have been detected in a wide range of animal species, including mammals and birds. Recently, a novel AstV associated with neurological symptoms has been detected in the brains of some mammals. Raccoon dog AstV has been reported recently in China. However, there have been no reports in South Korea. Therefore, the present study aimed to detect and genetically characterize AstVs in the intestine and brain tissues of 133 wild raccoon dogs collected in Korea between 2017 and 2019. Of the seven raccoon dogs, AstVs were detected in six intestinal tissues and four brain tissues. Analysis of the capsid protein amino acid sequences of raccoon dog AstVs detected in Korea revealed a high similarity to canine AstVs, suggesting possible interspecies transmission between raccoon dogs and dogs. Phylogenetic and capsid protein amino acid sequence analysis of raccoon dog AstVs detected in the brain the 17-148B strain belonging to the HMO clade and exhibiting conserved sequences found in neurotropic AstVs (NT-AstVs), indicating their potential as NT-AstVs. However, the pathogenicity and transmission routes of the raccoon dog AstV detected in Korea have not yet been elucidated, so further research and continued surveillance for AstV in wild raccoon dogs are needed.

Molecular characterization of oriental eyeworm (Thelazia callipaeda) detected from raccoon (Procyon lotor) and Japanese raccoon dog (Nyctereutes viverrinus) in Kanto region, Japan.

BACKGROUND: The oriental eyeworm Thelazia callipaeda (Spirurida: Thelaziidae) is an emerging parasitic ocular nematode of carnivores and humans. In domestic animals and humans, the infection causes varying degrees of inflammation and lacrimation, and wild carnivores represent an important reservoir. In this study we examined the infection status and molecular characterization of T. callipaeda in two urban carnivores, raccoons Procyon lotor and wild Japanese raccoon dogs Nyctereutes viverrinus, in the Kanto region of Japan. METHODS: From January 2020 to December 2021, 193 carcasses including 178 raccoons and 15 raccoon dogs were examined for the presence of worms in the eye. The worms from infected animals (one worm per host) were morphologically identified as T. callipaeda. Worms (1-5 worms per host) were subjected to genetic analysis using mitochondrial cytochrome c oxidase subunit I gene sequences. RESULTS: The prevalence of T. callipaeda in raccoons and Japanese raccoon dogs was 20.2% (36/178) and 13.3% (2/15), respectively. The cox1 sequences from 56 worms from 38 animals revealed three haplotypes (h9, h10, and h12). Analysis of multiple worms for five raccoons showed co-infection of two different haplotypes (h9 and h10) in a single host. Comparing our data with published sequences, three sequences obtained from raccoons and raccoon dogs shared the same haplotypes as those reported in humans, dogs, and cats in Japan. CONCLUSIONS: Our findings show a high prevalence of T. callipaeda in raccoons, suggesting that this invasive carnivore species serves as an important natural reservoir of T. callipaeda in the Kanto region of Japan, an area with the highest human population of the country.

History of Polish Canidae (Carnivora, Mammalia) and Their Biochronological Implications on the Eurasian Background.

The remains of 12 canid species that date back ca. 4.9 myr have been found at 116 paleontological localities. Among these localities, eight are dated to the Pliocene age, 12 are dated to the Early Pleistocene age, 12 are from the Middle Pleistocene age, while the most numerous group includes 84 sites from the Late Pleistocene-Holocene age. Some, especially older forms such as Eucyon odessanus and Nyctereutes donnezani, have only been found at single sites, while the remains of species from the genus Lycaon, Canis and Vulpes have been recorded at numerous sites from the last 2 myr. Ancient canids such as Eucyon and Nyctereutes had already vanished from Poland in the Earliest Pleistocene, between 2.5 and 2.2 myr ago. Poland's extant canid fauna is characterised by the presence of two new species, which spread into the territory due to a human introduction (Nyctereutes procyonoides) or natural expansion (Canis aureus). Research indicates a strong competition between dogs, especially between Lycaon, Canis and Cuon, with a strong lycaon-limiting effect on the wolf between 2.5 and 0.4 myr ago. After the extinction of Lycaon lycaonoides, Canis lupus evolved rapidly, increasing in number and size, and taking over the niche occupied by Lycaon. In order to reduce competition, the body size of Cuon alpinus gradually reduced, and it became an animal adapted to the forest, highland and mountain environments. Generally, the history of canids in Poland is similar to that known of Eurasia with some noteworthy events, such as the early occurrence of Canis cf. etruscus from Weze 2 (2.9-2.6 myr ago), Lycaon falconeri from Rebielice Królewskie 1A or one of the latest occurrences of L. lycaonoides from Draby 3 (430-370 kyr). Predominantly lowland or upland in the southern part and devoid of significant ecological barriers, Poland is also an important migration corridor in the East-West system. This 500-600 km wide corridor was the Asian gateway to Europe, from where species of an eastern origin penetrated the continent's interior. In colder periods, it was in turn a region through which boreal species or those associated with the mammoth steppe retreated.

RADIOGRAPHIC MEASUREMENT OF VERTEBRAL HEART SCALE IN KOREAN WILD RACCOON DOGS (NYCTEREUTES PROCYONOIDES KOREENSIS).

Raccoon dogs (Nyctereutes procyonoides koreensis), which belong to the Canidae family, are the second most injured wildlife animals rescued by the Gangwon Wildlife Medical Rescue Center. Various imaging evaluation methods including echocardiography have been developed, but thoracic radiography remains essential for the diagnosis and management of heart disease in dogs. In particular, vertebral heart scale (VHS) measurement is usually used to evaluate the dimensions of the heart silhouette on thoracic radiographs and can measure cardiomegaly more objectively. The VHS of 50 raccoon dogs without cardiac diseases were measured using thoracic radiography in right lateral (RL) and ventrodorsal (VD) recumbent positions. The VHS in the RL view of 50 raccoon dogs was 9.03 ± 0.52 vertebrae (v), which was slightly smaller than the VHS measured in the VD view of 46 raccoon dogs (9.79 ± 0.84 v). In addition, the thoracic morphology of raccoon dogs was determined to be intermediate (thoracic depth-to-width ratio, 0.75-1.25), and thoracic morphology, gender, and weight were not significantly correlated with VHS. The VHS of raccoon dogs in this study will help veterinarians diagnose potential cardiac diseases in raccoon dogs.

Alaria alata (Digenea: Diplostomidae) from Korean Raccoon Dog, Nyctereutes procyonoides koreensis, in Korea.

We report a species of diplostomid fluke recovered from 3 carcasses of wild Korean raccoon dog, Nyctereutes procyonoides koreensis, in Korea. A total of 107 diplostomid flukes were recovered from the small intestines of Korean raccoon dogs, which were obtained from the Gangwon Wildlife Medical Rescue Center. Worms fixed with 10% neutral formalin were subjected to microscopic observation and those fixed in 70% ethanol were used for molecular genomic analysis. The worm was divided into 2 separate parts, forebody and hindbody, with a total length of 3,020-4,090 (3,855) µm and a width of 1,210-1,770 (1,562) µm. The boat-shaped forebody has a pair of characteristic tentacular appendage, 2 suckers, holdfast organ, and vitelline follicles. The oval to cylindrical hindbody has reproductive organs. The ovary was round or elliptical and located in the anterior of the testes. Two large testes were slightly segmented and tandemly arranged, occupying almost half of hindbody. The short uterus contained a relatively small number of unembryonated eggs sized 130-140×85-96 µm. The partial sequence of 18S rRNA of this fluke was consistent with Alaria alata. Based on the morphological and molecular characteristics, the diplostomid flukes recovered from the small intestine of Korean raccoon dogs were identified as A. alata (Digenea: Diplostomidae).