Prevalence of canine distemper in minks, foxes and raccoon dogs from 1983 to 2023 in Asia, North America, South America and Europe.

Canine distemper (CD) is a virulent disease caused by the canine distemper virus (CDV) in canines and mustelidaes with high mortality. The incidence of CDV is worldwide distribution and it has caused huge economic losses to multiple industries around the world. There are many studies investigating the prevalence of CD infection, but no comprehensive analysis of CDV infection in minks, foxes and raccoon dogs worldwide has therefore been carried out. The aim of this meta is to provide a comprehensive assessment of the prevalence of CDV infection in minks, foxes and raccoon dogs dogs through a meta-analysis of articles published from around the world. Data from 8,582 small carnivores in 12 countries were used to calculate the combined prevalence of CD. A total of 22.6% (1,937/8,582) of minks, foxes and raccoon dogs tested positive for CD. The prevalence was higher in Asia (13.8, 95% CI: 22.2-45.6), especially in South Korea (65.8, 95% CI: 83.3-95.8). Our study found that the incidence of CD was also associated with geographic climate, population size, health status, and breeding patterns. CD is more commonly transmitted in minks, foxes and raccoon dogs. However, the concentrated breeding as an economic animal has led to an increase in the prevalence rate. The difference analysis study recommended that countries develop appropriate preventive and control measures based on the prevalence in the minks, foxes, and raccoon dogs industries, and that reducing stocking density is important to reduce the incidence of CDV. In addition, CDV is more common in winter, so vaccination in winter should be strengthened and expanded to reduce the incidence of CD in minks, foxes and raccoon dogs.

Immunogenicity of a novel inactivated canine adenovirus type 2 variant vaccine for dogs.

Purpose: The immunogenicity of vaccines containing the canine adenovirus (CAdV) type 2 (CAdV-2) variant has not yet been reported. We prepared a novel inactivated CAdV-2 variant vaccine using the CAV2232-41 strain, and evaluated its safety and immunogenicity in raccoon dogs. Materials and Methods: The growth kinetics of CAV2232-41 were determined using Madin-Darby Canine Kidney (MDCK) cells. The nucleotide sequences of CAV2232 and CAV2232-41 were determined by next-generation sequencing. To generate the CAdV-2 variant vaccine, CAV2232-41 propagated in the MDCK cells was inactivated with 0.1% formaldehyde. Two vaccines were prepared by blending inactivated CAV2232-41 with Cabopol and Rehydragel adjuvants. Safety and immunogenicity of the CAV2232C and CAV2232R vaccines were evaluated in guinea pigs. Safety and immunogenicity of the CAV2232C vaccine were also evaluated in raccoon dogs. The virus neutralizing antibody (VNA) titer against CAV2232-41 was measured in sera collected from immunized guinea pigs and raccoon dogs. Results: CAV2232-41 showed the highest viral titer on days 4-6 post-inoculation and had a deletion in the E3 gene, which was confirmed as a CAdV-2 variant. Guinea pigs inoculated with CAV2232C showed slightly higher VNA titers than those inoculated with CAV2232R 2 weeks after booster vaccination. Raccoon dogs immunized with the CAV2232C vaccine developed high mean VNA titers, while non-vaccinated raccoon dogs were antibody-negative. Conclusion: The CAV2232C vaccine is safe and induces a protective VNA titer in raccoon dogs.

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.

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.

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.

Dietary change influences the composition of the fecal microbiota in two rescued wild raccoon dogs (Nyctereutes procyonoides).

The gut microbiota of wild animals, influenced by various factors including diet, nutrition, gender, and age, plays a critical role in their health and disease status. This study focuses on raccoon dogs (Nyctereutes procyonoides), a commonly found wild animal, and its gut microbiota composition in response to dietary shifts. The study aimed to compare the fecal bacterial communities and diversity of rescued raccoon dogs fed three different diet types (fish and amphibians, mixed protein with maize, and solely maize) using high-throughput sequencing. Results indicated that the dietary composition significantly influenced the gut microbiota, with notable differences in the abundance of several key phyla and genera. The study identified Firmicutes as the dominant phylum in all diet groups, with notable variations in the relative abundances of Bacteroidota, Proteobacteria, and Verrucomicrobiota. Notably, the group solely fed maize exhibited a significant increase in Proteobacteria, potentially linked to dietary fiber and lignin degradation. The genus-level analysis highlighted significant differences, with Lactobacillus and Bifidobacterium responding to dietary shifts. The genus Akkermansia in Verrucomicrobiota can be identified as a marker for assessing the health of the gut and deserves further investigation. Gender-specific differences in the gut microbiota were observed, highlighting the influence of individual variation. Furthermore, the analysis of bacterial functions suggested a connection between diet and host metabolism, emphasizing the need for further research to understand the complex mechanisms underlying the relationship between dietary composition and gut microbiota in wild animals. These findings provide crucial insights into conservation and rescue efforts for wild animals.

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.

Effect of Cyberlindnera jadinii supplementation on growth performance, serum immunity, antioxidant status, and intestinal health in winter fur-growing raccoon dogs (Nyctereutes procyonoides).

Introduction: This study aimed to investigate the effects of Cyberlindnera jadinii supplementation on the growth performance, nutrient utilization, serum biochemistry, immunity, antioxidant status, and intestinal microbiota of raccoon dogs during the winter fur-growing period. Methods: Forty-five 135 (±5) day-old male raccoon dogs were randomly assigned to three dietary groups supplemented with 0 (group N), 1 × 109 (group L) and 5 × 109 CFU/g (group H) Cyberlindnera jadinii, with 15 raccoon dogs per group. Results: The results showed that Cyberlindnera jadinii in groups L and H improved average daily gain (ADG) and decreased feed-to-weight ratio (F/G) (P < 0.05). No significant difference was found in nutrient digestibility and nitrogen metabolism among the three groups (P > 0.05). Compared with group N, serum glucose levels were lower in groups L and H (P < 0.05). The levels of serum immunoglobulins A and G in group L were higher than those in the other two groups (P < 0.05), and the levels of serum immunoglobulins A and M in group H were higher than those in group N (P < 0.05). Supplementation with Cyberlindnera jadinii in groups L and H increased serum superoxide dismutase activity, and the total antioxidant capacity in group H increased compared with group N (P < 0.05). The phyla Bacteroidetes and Firmicutes were dominant in raccoon dogs. The results of principal coordinate analysis (PCoA) showed that the composition of microbiota in the three groups changed significantly (P < 0.05). The relative abundance of Campylobacterota was increased in the H group compared to the N and L groups (P < 0.05). The relative abundance of Sarcina was increased in group L compared with the other two groups (P < 0.05), while the relative abundance of Subdoligranulum and Blautia were decreased in group H compared with the other two groups (P < 0.05). Also, the relative abundance of Prevotella, Sutterella and Catenibacterium was higher in group L (P < 0.05) compared with group H. Discussion: In conclusion, dietary supplementation with Cyberlindnera jadinii improved growth performance, antioxidant activity, immune status, and improved intestinal microbiota in winter fur-growing raccoon dogs. Among the concentrations tested, 1 × 109 CFU/g was the most effective level of supplementation.

Mannan oligosaccharides improve the fur quality of raccoon dogs by regulating the gut microbiota.

Introduction: Adding antibiotics to animal basal diets can improve growth and production performance. However, the use of antibiotics poses a potential threat to public health safety. Methods: The study was conducted to investigate the effects of different levels of mannan oligosaccharides (MOS) on the fur quality, nutrient apparent digestibility, serum immunity, antioxidant status, intestinal morphology, and gut microbiota of fur-growing raccoon dogs. Divide 24 male raccoon dogs (120 ± 5 d) of similar weight (5.01 ± 0.52 kg) into 4 groups randomly. Add 0, 0.05, 0.1, and 0.2% MOS to the basal diets of groups C, L, M, and H, respectively. Results: Compared to the C group, the addition of 0.05% and 0.1% MOS in the diet increased the apparent digestibility of crude protein (CP), Underfur length (UL), Guard hair length (GL), immunoglobulin A (IgA), immunoglobulin G (IgG), and immunoglobulin M (IgM) levels in the serum (p < 0.05); Under the dosage of 0.05 % MOS, the activities of Superoxide Dismutase (SOD) and catalase (CAT) increased (p < 0.05). Compared to the C group, adding 0.05% MOS significantly increased the VH/CD of the duodenum and ileum, while also increasing the VH and CD of the jejunum (p < 0.05). Through Spearman correlation analysis of the gut microbiota, it was found that MOS can improve fur quality by reducing the abundance of Dorea while improving the immune response of raccoon dogs by reducing the abundance of Blautia and Gemmiger. Discussion: In conclusion, MOS can improve the fur quality, serum immunity, antioxidant capacity, and gut microbiota of raccoon dogs. Therefore, MOS has the potential to replace antibiotics.

Evolutionary analysis of Babesia vulpes and Babesia microti-like parasites.

BACKGROUND: The Babesia microti-like parasite is an emerging tick-borne piroplasm that has been detected in a range of hosts worldwide. Babesia vulpes, which is found in dogs and foxes, has been reclassified from B. microti-like parasites. The relationships among these B. microti-like parasites and B. vulpes with respect to host range and geographical origin have not been elucidated. METHODS: Blood samples were collected from 27 raccoon dogs in South Korea and used to screen for B. microti-like parasites based on a PCR assay targeting the 18S rRNA gene of Babesia. For comparative purposes, in addition to 18S rRNA sequences from nine raccoon dogs, we also analyzed 18S rRNA sequences from B. microti-like parasites infecting hosts in different geographical regions worldwide obtained from the GenBank database, giving 123 sequences in total. The genetic variation and evolutionary relationships among these sequences were examined based on analyses using DnaSP, MEGA, Arlequine, and BEAST software. RESULTS: Babesia microti-like parasites were identified in nine raccoon dogs and found to be related to B. vulpes obtained from Spanish dogs. Among the 123 sequences from 14 countries and various hosts, we identified 43 haplotypes with high genetic variance. Based on the genetic variance and phylogenetic analyses, we established that the B. microti-like parasites isolated in different geographical regions and from hosts belonging to five orders showed higher among-population variation than within-population variation. Babesia vulpes parasites infecting carnivore hosts, including raccoon dogs, foxes, skunks and dogs, appear to be genetically distinct from B. microti-like parasites infecting hosts belonging to the other orders. CONCLUSIONS: Our study demonstrated the genetic variation and evolutionary relationships among 18S rRNA sequences obtained from blood samples collected from various hosts and different geographical regions. Babesia vulpes was identified from raccoon dogs in South Korea. In addition, higher genetic variations were observed among populations of different hosts and geographical origins and, in particular, low connectivity was observed among host populations in the order Carnivora and those in other orders. These results suggest the B. vulpes, a piroplasmid species pathogenic in domestic dogs and wild canines, is genetically and evolutionarily different from B. microti-like parasites.

Dietary supplementation with Cyberlindnera jadinii improved growth performance, serum biochemical Indices, antioxidant status, and intestinal health in growing raccoon dogs (Nyctereutes procyonoides).

This study was conducted to investigate whether different dietary Cyberlindnera jadinii levels affect growth performance, serum immunity, antioxidant capacity, and intestinal microbiota in growing raccoon dogs. Forty-five healthy male raccoon dogs were randomly assigned to three treatment groups, with 15 raccoon dogs per group. Each raccoon dog was housed in an individual cage. The raccoon dogs in the three groups were fed diets supplemented with Cyberlindnera jadinii at dosages of 0 (N group), 1 × 109 (L group) and 5 × 109 CFU/g (H group). A 7-day pretest period preceded a formal test period of 30 days. The results showed that Cyberlindnera jadinii in the L and H groups improved average daily gain (ADG) (P < 0.05) and decreased the ratio of feed to weight (F/G) (P < 0.05). Serum immunoglobulins A and G levels were increased in the L and H groups compared to the N group (P < 0.05). Cyberlindnera jadinii in the L and H groups increased serum superoxide dismutase activity (P < 0.05), and serum glutathione peroxidase activity was increased in the L group compared to the N group (P < 0.05). The relative abundance of Firmicutes and Actinobacteriota were increased, and the relative abundance of Bacteroidota was decreased in the L and H groups compared to the N group (P < 0.05). The relative abundance of Proteobacteria and Cyanobacteria was increased in the H group compared to the other two groups (P < 0.05). The ratio of Firmicutes to Bacteroidetes in the Cyberlindnera jadinii supplementation groups increased compared with the N group (P < 0.05). The relative abundance of Megasphaera and Bifidobacterium were increased, and the relative abundance of Prevotella was decreased in the L and H groups compared to the N group (P < 0.05). The relative abundance of Dialister was increased, while the relative abundance of Blautia was decreased in the H group compared to the other two groups (P < 0.05). The relative abundance of Agathobacter was decreased in the H group compared to the N group (P < 0.05). In conclusion, dietary supplementation with Cyberlindnera jadinii increased growth performance, serum immunity, antioxidant capacity, and improved intestinal microbiota in growing raccoon dogs. Cyberlindnera jadinii can therefore be used as a growth promoter in raccoon dogs.

Antimicrobial resistance in Escherichia coli isolates from Japanese raccoon dogs (Nyctereutes viverrinus) in Kanagawa Prefecture, Japan: Emergence of extended-spectrum cephalosporin-resistant human-related clones.

Introduction. Wild animals are one of the putative reservoirs of antimicrobial-resistant bacteria, but the significance of raccoon dogs remains to be investigated.Hypothesis. Raccoon dogs can be a reservoir of antimicrobial-resistant bacteria.Aim. This study aimed to explore the prevalence of antimicrobial resistance, mainly extended-spectrum cephalosporins resistance, in Escherichia coli isolates from faeces of 80 Japanese raccoon dogs in Kanagawa Prefecture, Japan.Methodology. All of the 80 faecal samples were streaked onto deoxycholate-hydrogen sulfate-lactose (DHL) and cefotaxime (CTX)-supplemented DHL (DHL-CTX) agars. Susceptibilities to ten antimicrobials were determined using the agar dilution method. Additionally, extended-spectrum ß-lactamases (ESBLs) and AmpC-type ß-lactamases (ABLs) were identified in addition to sequence types (STs), in ESC-resistant isolates by a polymerase chain reaction and sequencing.Results. Out of all the samples, 75 (93.8 %) and 20 (25.0 %) E. coli isolates were isolated by DHL and DHL-CTX agars, respectively. Significantly higher resistance rates to most of the drugs were found in DHL-CTX-derived isolates than DHL-derived isolates (P<0.01). Genetic analysis identified CTX-M-14 (n=6), CTX-M-2 (n=2), CTX-M-1 (n=1) and CTX-M-55 (n=1) as ESBLs, and CMY-2 (n=8) and DHA-1 (n=1) as ABLs in 20 DHL-CTX-derived isolates. Most of the detected STs were related to Japanese humans (i.e. ST10, ST58, ST69, ST131, ST357, ST648 and ST4038). Notably, this is the first report on ST69, ST131, ST155 and ST648, which are well-known international high-risk clones in Japanese raccoon dogs.Conclusion. Our findings underscore the need to understand the significance of raccoon dogs as an antimicrobial-resistant bacteria reservoir using one health approach.

Leptospiral meningoencephalitis in a raccoon dog.

Neuroleptospirosis is a rare disease caused by pathogenic Leptospira interrogans in humans; however, it has not been fully studied in animals. A young wild raccoon dog was found convulsing in the recumbent position and died the next day. Histologic examination revealed nonsuppurative meningoencephalitis in the cerebrum, cerebellum, midbrain, and medulla oblongata. The lesions consisted of mixed infiltrates of Iba1-positive macrophages and CD3-positive T cells, with a small number of CD79α-positive B cells and myeloperoxidase-positive neutrophils. In the frontal cortex, perivascular cuffs and adjacent microglial nodules were distributed diffusely, especially in the molecular layer. Glial nodules were comprised of Iba1- and myeloperoxidase-positive activated microglia. Immunohistochemistry revealed leptospires in mononuclear cell perivascular cuffs, but not in glial nodules. Neuroleptospirosis was accompanied by Leptospira-related nonsuppurative interstitial nephritis, pulmonary edema and hemorrhage, and coronary periarteritis, as well as Toxocara tanuki in the small intestine and nonspecific foreign-body granulomas in the lungs and stomach.

First report of norovirus sequences isolated from raccoon dogs in mainland China.

Noroviruses can infect humans and a wide variety of other mammalian hosts, causing varying degrees of diarrhea. In this study, two novel norovirus genomes were identified for the first time in farmed raccoon dogs, designated as raccoon dog noroviruses BUCT-K1 and BUCT-K4. Neither the farmers nor the raccoon dogs had symptoms (e.g., diarrhea) at the time of sample collection. We collected 14 stool samples from two farms, and 85.7% (12/14) of the samples were norovirus positive by RT-PCR. The two norovirus genomes have the highest identity to Dog/Z7/19/CH, suggesting that the norovirus might have been transmitted from dogs to raccoon dogs. Genomic and evolutionary analyses indicated that different directions of evolution occurred following the spread of the norovirus to the raccoon dogs. This study has increased knowledge of norovirus-infected animal species and has provided additional information on the norovirus family.

Viral Metagenomics Reveals Diverse Viruses in the Feces Samples of Raccoon Dogs.

Raccoon dogs as an ancient species of Canidae are the host of many viruses, including rabies virus, canine distemper virus, severe acute respiratory syndrome coronavirus, and so on. With the development of raccoon dog breeding in recent years, some viruses which infected poultry or pigs were also detected from raccoon dogs. At present, the fecal virome of raccoon dogs has been rarely studied. Using an unbiased viral metagenomic approach, we investigated the fecal virome in raccoon dogs collected from one farm of Jilin Province, China. Many DNA or RNA viruses identified in those fecal samples were mainly from seven families, including Circoviridae, Smacoviridae, Genomoviridae, Parvoviridae, Picornaviridae, Astroviridae, and Hepeviridae. This study increased our understanding of the fecal virome in raccoon dog and provided valuable information for the monitoring, prevention, and treatment of viral diseases of these animals.

Radiographic evaluation of congenital vertebral anomalies in Korean raccoon dogs (Nyctereutes procyonoides koreensis).

BACKGROUND: The normal vertebral anatomy of Korean raccoon dogs and their variants require research attention as a prerequisite for identifying pathologies and anomalies. OBJECTIVES: This retrospective study aimed at describing the vertebral formula and congenital vertebral anomalies in Korean raccoon dogs (Nyctereutes procyonoides koreensis). METHODS: Radiographs of 82 raccoon dogs (42 males, 40 females) acquired from May 2013 to June 2020 in the Gangwon Wildlife Medical Rescue Center were reviewed to evaluate the cervical, thoracic, and lumbar vertebrae of the spine. RESULTS: Normal morphology of all vertebrae was observed in 50 of the 82 raccoon dogs, and the vertebral formula was cervical 7, thoracic 13, and lumbar 7. Congenital vertebral anomalies were found in 32 raccoon dogs: transitional vertebrae (TV) in 31 and block vertebrae in 2. Two raccoon dogs had 2 types of vertebral anomalies: one had TV and block vertebra, and the other had 2 types of TV. Twenty-nine raccoon dogs had thoracolumbar TV (TTV) and 3 had lumbosacral TV. TTV was morphologically classified into 4 different types: unilateral extra-rib in 5 raccoon dogs, bilateral extra-ribs in 14, bilateral elongated transverse processes in 4, and an asymmetric mixed formation of extra-rib with elongated transverse process in 6. CONCLUSIONS: This study showed that TTV is common in Korean raccoon dogs, and that the vertebral formula is relatively diverse. The bilateral extra-ribs type TTV is the most common variant, which is almost similar to normal rib to be confused the radiographic evaluation.

Molecular characteristics of H9N2 influenza viruses isolated from farmed raccoon dogs and arctic foxes in China.

In this study, eight H9N2 IAVs were isolated from infected diseased, farmed raccoon dogs and arctic foxes. Eight genes shared 98.6%-100% identity among the isolates possessing a PSRSSR/GL motif at the HA cleavage site, which is same as the motif of G1 and Y280 lineages of H9N2 IAVs. The phylogenetic analysis showed that the HA genes of the eight isolates clustered with Y280-like viruses, whereas the NA genes belonged to F/98-like sublineage. Interestingly, the NS, NP, PB2 and PA genes of the isolates were closely related to H7N9 IAVs. This is the first evidence for isolation of H9N2 IAVs from raccoon dogs and arctic foxes. Raccoon dogs and arctic foxes potentially serve as an intermediate host for influenza viruses with pandemic potential toward other animals due to co-expression of both SA α-2,6-Gal and SA α-2,3-Gal receptors in a wide range of their tissues.

Susceptibility of Raccoon Dogs for Experimental SARS-CoV-2 Infection.

Raccoon dogs might have been intermediate hosts for severe acute respiratory syndrome-associated coronavirus in 2002-2004. We demonstrated susceptibility of raccoon dogs to severe acute respiratory syndrome coronavirus 2 infection and transmission to in-contact animals. Infected animals had no signs of illness. Virus replication and tissue lesions occurred in the nasal conchae.

Cardiopulmonary nematodes of wild carnivores from Denmark: Do they serve as reservoir hosts for infections in domestic animals?

The cardiopulmonary nematodes Angiostrongylus vasorum, Crenosoma vulpis, Capillaria aerophila and Aelurostrongylus abstrusus, are a cause of concern in the scientific and veterinary community, potentially causing significant disease in domestic animals. To investigate the potential of wild carnivores as reservoir hosts to these parasites, a total of 1041 animals from seven regions of Denmark were sampled: 476 raccoon dogs (Nyctereutes procyonoides), 367 red foxes (Vulpes vulpes), 123 American mink (Neovison vison), 31 beech martens (Martes foina), 30 Eurasian otters (Lutra lutra) and 14 polecats (Mustela putorius). Hearts and lungs were collected and examined for cardiopulmonary parasites. Capillaria aerophila was identified using morphology, whereas A. vasorum and C. vulpis were identified by a duplex real-time PCR, and A. abstrusus by conventional PCR. This is the first Danish report of A. vasorum and C. vulpis infections in raccoon dogs, mink and polecats, and of C. aerophila in raccoon dogs and beech martens. In addition, this is the first time A. vasorum and C. vulpis have been identified in wild animals from the island of Bornholm, just as it is the first report of C. vulpis in American mink, and C. vulpis and A. vasorum in polecats in Europe. The prevalence of A. vasorum appears to have increased in red foxes in Denmark compared to previous studies, while C. vulpis and C. aerophila prevalences are lower. Our data show that several wild carnivores can serve as reservoir hosts for A. vasorum, C. vulpis and C. aerophila in Denmark, and that A. vasorum appears more abundant than previously reported. It is speculated that the A. vasorum increase might relate to increased snail abundance, which may be due to a rise in mean yearly temperatures in Denmark.

Prevalence and genotype distribution of Enterocytozoon bieneusi in farmed raccoon dogs (Nyctereutes procyonoides) in Shandong Province, eastern China.

Enterocytozoon bieneusi is a common microsporidian species, which can infect humans and various species of animals. However, little is known about E. bieneusi prevalence and genotypes in farmed raccoon dogs (Nyctereutes procyonoides) in Shandong Province, China. In this study, a total of 356 fecal samples were collected from farmed raccoon dogs in Weihai, Weifang, and Yantai cities in Shandong Province, China. A total of 23 (6.5%) samples were E. bieneusi-positive by nested PCR amplification of the internal transcribed spacer (ITS) region of ribosomal DNA. Statistical analysis showed that E. bieneusi prevalence in male raccoon dogs was higher than that in female raccoon dogs, and the highest E. bieneusi prevalence was detected in adult raccoon dogs. Sequence analysis revealed four known E. bieneusi genotypes (D, type IV, CHG1, and Peru8), and type IV (11/23) was the predominant genotype. The genotypes type IV, Peru8, and CHG1 were reported in raccoon dogs for the first time in China. Phylogenetic analysis showed that three human-pathogenic genotypes (D, type IV, and Peru8) were clustered into group 1, and the CHG1 belonged to group 2. These findings expand the current understanding of E. bieneusi prevalence and genotype distribution in raccoon dogs in China. Our study also shows that raccoon dogs are hosts for E. bieneusi belonging to several genotypes, including zoonotic ones, highlighting the possibility of transmission of this pathogen between raccoon dogs and humans.