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The COVID-19 pandemic, caused by SARS-CoV-2, demonstrated that zoonotic transmission of animal sarbecoviruses threatens human health but the determinants of transmission are incompletely understood. Here, we show that most spike (S) proteins of horseshoe bat and Malayan pangolin sarbecoviruses employ ACE2 for entry, with human and raccoon dog ACE2 exhibiting broad receptor activity. The insertion of a multibasic cleavage site into the S proteins increased entry into human lung cells driven by most S proteins tested, suggesting that acquisition of a multibasic cleavage site might increase infectivity of diverse animal sarbecoviruses for the human respiratory tract. In contrast, two bat sarbecovirus S proteins drove cell entry in an ACE2-independent, trypsin-dependent fashion and several ACE2-dependent S proteins could switch to the ACE2-independent entry pathway when exposed to trypsin. Several TMPRSS2-related cellular proteases but not the insertion of a multibasic cleavage site into the S protein allowed for ACE2-independent entry in the absence of trypsin and may support viral spread in the respiratory tract. Finally, the pan-sarbecovirus antibody S2H97 enhanced cell entry driven by two S proteins and this effect was reversed by trypsin while trypsin protected entry driven by a third S protein from neutralization by S2H97. Similarly, plasma from quadruple vaccinated individuals neutralized entry driven by all S proteins studied, and availability of the ACE2-independent, trypsin-dependent pathway reduced neutralization sensitivity. In sum, our study reports a pathway for entry into human cells that is ACE2-independent, can be supported by TMPRSS2-related proteases and may be associated with antibody evasion. Author summary: Bats host a wide range of coronaviruses, including those related to SARS-CoV-1 and SARS-CoV-2 (subgenus Sarbecovirus), but their ability to infect human cells remains poorly understood. Identifying sarbecoviruses with zoonotic potential and understanding the factors controlling their entry into human cells are crucial for risk assessment and antiviral development. In this study, we examined how bat sarbecovirus spike proteins facilitate entry into human cells and identified key host factors involved. Using pseudovirus particles, we show that several bat sarbecovirus spike proteins use human and animal ACE2 receptors for entry. Additionally, we confirm that some spike proteins utilize an ACE2-independent entry pathway requiring trypsin treatment and demonstrate that this process is controlled by the spike protein receptor binding domain. Furthermore, we reveal that a subset of ACE2-using bat sarbecovirus spike proteins can switch to ACE2-independent entry following trypsin exposure and show that certain human type II transmembrane serine proteases can substitute for trypsin, enabling ACE2-independent entry. Finally, we demonstrate that repeated COVID-19 vaccination generates cross-neutralizing activity against bat sarbecoviruses, though ACE2-independent entry reduces neutralization sensitivity. [ABSTRACT FROM AUTHOR]

Background: Carnivore parvovirus is commonly detected in canines and felines and results in a range of symptoms, including diarrhoea, with a high lethality rate. In recent years, the gradual restoration of urban ecosystems coupled with a lack of natural predators means that wild raccoon dogs have gradually entered residential neighbourhoods in Shanghai, and the carnivore parvovirus carried by such canines may seriously affect their health and that of dogs and cats in these neighbourhoods. Objectives: Therefore, it is essential to monitor wild raccoon dogs for carnivore parvovirus. Methods: The wild raccoon samples were collected from the residential area of Shanghai and screened for parvovirus, followed by virus isolation and sequence comparison analysis. Results: In this study, three strains of parvovirus, YSH1‐2022, YSH2‐2022 and GSW1‐2023, were isolated from anal and pharyngeal swab mixtures of 42 live raccoon dogs and two dead raccoon dogs in Shanghai, China. After alignment, it was found that the three strains of parvovirus were all located in the same branch as feline panleukopenia virus (FPV), and the three VP2 genes had 100% homology with FPV VP2 genes isolated from Shanghai and Yangzhou, Jiangsu Province. The homology of the three NS1 genes with FPV NS1 isolated from Shanghai and other places was 99.9%–100%. Conclusion: This is the first report of FPV isolated from raccoon dogs. In this study, the host range and risk of infection of parvovirus were evaluated, providing data to support wildlife management and policy formulation in Shanghai. [ABSTRACT FROM AUTHOR]

Social Impact Statement: Gingko biloba is an iconic tree with a surprising connection to the SARS and Covid viruses that have impacted human health since 2003. Natural history studies on the ecology of Gingko seed dispersal by Carnivoran scavengers in Asia over the past 30 plus years have elucidated the deep evolutionary history that not only makes these animals effective at spreading seeds but also predisposes them to become intermediate hosts for spreading diseases to humans. Understanding the behavioral traits that underlie these kinds of plant–animal interactions has the potential to help people limit the spread of future spillover diseases. Summary: Raccoon dogs and masked palm civets are Carnivoran scavengers native to Eastern Asia that have been documented feeding on the malodorous sarcotesta of Ginkgo biloba seeds and effectively dispersing the hard nuts they contain. Research has shown that their immune systems are genetically enhanced to protect them from the disease‐causing organisms they might pick up from their omnivorous diets that include live and dead animals. Both species are farmed for fur and meat across China and, up until recently, were commonly sold in "wet" markets. Research has determined that the palm civet played a role in spreading the SARS virus to humans in 2003 and that the raccoon dog may have played a similar role in spreading Covid in Wuhan in 2019, although this has not been proven. In areas where Ginkgo is cultivated, there are numerous internet reports of Carnivorans feeding on its seeds indicating that its dispersal strategy of attracting scavengers by mimicking the smell of carrion is adaptive and effective. [ABSTRACT FROM AUTHOR]

Monitoring both native and invasive species is crucial for understanding their ecological impacts. However, obtaining reliable data can be challenging, especially for elusive species like mesopredators. This study utilized snow-track surveys in Finland (1989–2022) to examine population trends of the invasive raccoon dog and the native red fox. While raccoon dogs are known to reduce activity during cold weather, we demonstrated that accounting for temperature and snowfall allows for effective population trend estimation using snow-track data. Track accumulation decreased in cold and snowy weather more clearly for raccoon dogs than for red foxes. We also found that the track accumulation of the raccoon dog had significantly increased, while those of the red fox population had declined, particularly in southern parts of the country. Notably, raccoon dog snow-track numbers increased in northern regions, suggesting a potential for further range expansion under a warming climate. These findings reveal a concerning shift in Finland's mesopredators abundance due to the invasive species' success and the decline of the native species. Thus, the invasive raccoon dog is likely to have an increasing role in those northern ecosystems where it interacts with the native fauna. [ABSTRACT FROM AUTHOR]

Wind farms are still developing dynamically worldwide, with promising prospects for further growth. Therefore, the assessment of their impact on animals has been carried out. So far, few studies have been conducted on game mammals, and their results are divergent. Previous studies on the impact of wind farms on game species were typically based on regional research covering one or, at most, several wind farms. In this study, we aimed to verify the effect of wind farms on the density of game mammals through a large-scale analysis at the country level, using lowland Poland as an example. The study was based on hunting bag data from open-field hunting districts. It covered seven game species: roe deer (Capreolus capreolus), wild boar (Sus scrofa), red fox (Vulpes vulpes), raccoon dog (Nyctereutes procyonoides), European badger (Meles meles), European polecat (Mustela putorius), and European hare (Lepus europaeus). We used Corine Land Cover to account for differences in land cover and the area covered by wind farms in generalized linear mixed models. The study showed that in agricultural landscapes, mainly herbivorous species of game mammals were related to land cover types. These species tend to exhibit higher densities in agricultural areas containing more natural landscape features. Conversely, mesocarnivores are primarily driven by the abundance of prey with little to no observable effects from land cover types. Only roe deer and wild boar presented lower densities with an increase in the area covered by wind farms (for roe deer: estimate: − 0.05, 95% CI: − 0.1–0.0; for wild boar: estimate: − 0.03, 95% CI: − 0.11–0.05), while no effect was observed for mesocarnivores or European hare. The underlying reasons for these relationships remain unclear and require more specific studies. The uncertainty regarding the cause of the observed effects did not allow for a large-scale assessment of the impact of further wind energy development on the studied game mammals. [ABSTRACT FROM AUTHOR]

Simple Summary: Habitat loss and fragmentation from extensive road development have escalated wildlife–vehicle collisions (WVCs) as a major cause of wildlife mortality. This study covers 9 years of WVC data across South Korea, examining species involved, seasonal and regional variations, and road factors affecting WVCs, to analyze impacts and propose mitigation strategies. Over 4561 km of roads were monitored, yielding insights into the connection between WVCs, road characteristics, and species-specific patterns. The study identified 13,606 WVCs involving 143 terrestrial vertebrate species, with detailed patterns and models for the top seven mammal species. Spatial differences in WVCs appeared more related to wildlife habitats, but some road features correlated variably with WVC frequency, highlighting complex prevention challenges. Effective mitigation requires comprehensive strategies tailored to species traits, seasonality, and road types. Severe habitat loss and fragmentation due to extensive road development have escalated wildlife–vehicle collisions (WVCs) as one of the major causes of wildlife mortality. This study, spanning 9 years from 2009 to 2017, presents comprehensive WVC data in South Korea, including species composition, seasonal and regional patterns, and road factors influencing WVCs, aiming to analyze their impact and propose effective mitigation strategies. We collected WVC data with road variables for 9 years from 4561 km of nationwide monitoring road sections and analyzed the data to understand the relationship between WVCs and road characteristics, as well as species-specific patterns. A nationwide survey identified 13,606 WVCs involving 143 terrestrial vertebrate species, and patterns and models of the top seven mammal species (raccoon dog (Nyctereutes procyonoides), Siberian chipmunk (Eutamias sibiricus), Siberian weasel (Mustela sibirica), water deer (Hydropotes inermis), red squirrel (Sciurus vulgaris), Korean hare (Lepus coreanus), and leopard cat (Prionailurus bengalensis)) were presented. Patterns revealed declines in WVCs overall, except for water deer. Although spatial differences in WVCs seemed linked more to wildlife habitats, certain road features correlated both positively or negatively with WVC frequency, highlighting complexities in the effectiveness of preventative measures. For effective mitigation and prevention of WVCs, comprehensive strategies considering species traits, seasonality, and road types should be implemented [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Habitat preferences of invasive predators determine where and for which prey species they pose a threat upon. This is crucial information for the conservation of endangered prey species because invasive predators pose additional predation on top of that caused by natural predators. In large parts of Europe, the most common invasive mesopredator is the raccoon dog (Nyctereutes procyonoides). To understand the risk that the raccoon dog poses for wetland-associated species, we collected information about its habitat preferences near these habitats. We used data on 24 GPS-collared raccoon dogs from three landscape types in Finland, to study their spatial and temporal habitat preferences. We first determined their home ranges, within which we then examined habitat use and preferences. Raccoon dogs showed generalist habitat use, which was evident in their wide range of used habitats. However, in spring and summer, during the breeding seasons of waterfowl and amphibians, they preferred wetlands and peatlands. They also preferred shorelines and the edges of forests and agricultural fields. During autumn and winter, raccoon dogs did not prefer wetlands. These findings support the conclusion that the raccoon dog's habitat preferences pose a particular threat to wetland-associated species, such as nesting waterfowl and amphibians. The species' habitat preferences coupled with high numbers of this invasive mesopredator pose additional predation for endangered wetland-associated species on top of that of native predators. [ABSTRACT FROM AUTHOR]

Simple Summary: The Korean raccoon dog (Nyctereutes procyonoides koreensis) is an important species in Korea. However, there has been little research about its joint anatomy. In this study, we investigated the anatomy of the limb joints of the Korean raccoon dog using joint orientation angles, a method frequently used in humans, dogs, and cats. The findings of this study should be helpful not only for individual therapies, such as fracture repair, but also for comparative anatomy. Furthermore, this study is the first to measure joint orientation angles in wild animals such as the Korean raccoon dog, making it a useful reference for measurements in other wild canids. Studies are being conducted on the anatomical structures of various wild animals. Despite the ecological importance of the Korean raccoon dog (Nyctereutes procyonoides koreensis), limited research has been conducted on its anatomical structure. This study is the first to establish a reference range for joint orientation angles in the limbs of the Korean raccoon dog. Joint orientation angles are an unexplored concept not only in Korean raccoon dogs but also in other wildlife. However, they are important in the examination of the skeletal anatomy of humans and companion animals, such as dogs and cats. Because this type of measurement is still emerging in wildlife research, we applied the methodology used in the domestic dog (Canis lupus familiaris). Angles were measured between the mechanical or anatomical axis and the joint orientation lines in the thoracic and pelvic limbs of Korean raccoon dogs. No significant differences were observed between the sexes or between the left and right sides. These findings are consistent with those observed in domestic dogs. Based on this study, a reference range of joint orientation angles could be established for Korean raccoon dogs. [ABSTRACT FROM AUTHOR]

With the increase in the number of urban wildlife, some residents feel anxious and fearful due to the presence of wildlife in urban communities, even when there is no direct physical conflict between them. This research aims to analyze the role of citizen science in increasing residents' tolerance towards urban wildlife. This research takes the communities with the highest raccoon dog density in Shanghai as the research sites. Forty respondents were selected from local community by systematic sampling. Information was collected through semi-structured interviews and participatory observation. This research used NVivo 12 for thematic analyses. The research found that residents who did not participate in citizen science tended to take crisis observation. They regard raccoon dogs as dangerous wildlife and strictly monitor their behavior to prevent them from causing harm to humans. Residents who are engaging in citizen science tend to take scientific observations. They rationally and objectively record raccoon dogs' behavior, numbers, and distribution. Based on the experience of scientific observation, residents who had participated in citizen science anthropomorphically observed raccoon dogs in their daily lives and established an emotional bond with them. This research found that citizen science enhances residents' tolerance towards urban wildlife by producing knowledge and perceiving animal selfhood. In conclusion, this research reveals the complex relationship between residents and wildlife in urban communities by incorporating animals into sociological analysis. [ABSTRACT FROM AUTHOR]

Canine adenovirus type 2 (CAV-2) is a common causative agent of respiratory disease in canines. There have been no reports of CAV-2 variants isolated from raccoon dogs. This study aims to investigate the biological and genetic characteristics of a novel Korean CAV-2 variant. Madin-Darby canine kidney cells were used to isolate the CAV-2 variant from 45 fecal swab samples. Diagnostic tools such as the cytopathic effect (CPE) assay, electron microscopy, polymerase chain reaction, and immunofluorescence and hemagglutination assays were used to confirm the presence of the CAV-2 isolate. A cross-virus neutralization assay was performed to verify the novelty of this CAV variant. Genetic analysis was performed using nucleotide sequences obtained through next-generation sequencing. The isolate was confirmed to be a CAV-2 variant based on the aforementioned methods and designated CAV2232. The number of bases in the fiber and E3 genes of CAV2232 were 1,626 and 414, respectively. Phylogenetic analysis of the fiber and E3 genes confirmed that CAV2232 was classified into a different clade from the known CAV-1 and CAV-2 strains. Mice inoculated with the CAV2232 vaccine developed high virus neutralization antibody titers of 1,024 (210) against CAV2232, while mice inoculated with CAV-1 and CAV-2 vaccines had low virus neutralization antibody titers of 12.9 (23.7) and 6.5 (22.7), respectively, against CAV2232. CAV2232 isolated from wild raccoon dog feces was classified as a novel CAV-2 variant. CAV2232 may therefore be used as an antigen for new vaccine development and serological investigations. [ABSTRACT FROM AUTHOR]

Sustainable wildlife management requires reliable data on population, habitat, and the interaction between them. Since 1993, Hungary has maintained the National Game Management Database, which collects data on game populations and hunting bags annually. During the last three decades, populations of medium-sized predators have remarkably increased in the country. Our study analyzed changes in hunting bag data and spatial distribution of two invasive alien species, the raccoon (Procyon lotor) and the raccoon dog (Nyctereutes procyonoides), utilizing annual game management reports from Game Management Units from 1997 to 2021. For spatial analysis, we employed a UTM grid system (10 × 10 km) covering the country. Our findings confirmed increasing trends in the hunting bag and area (number of grid cells) containing hunting bags for both species. From the first (1997–2001) to the last (2017–2021) period, the average annual hunting bag increased (raccoon: 0.40 → 11.00 ind/year; raccoon dog: 3.40 → 8.00 ind/year), and the average number of cells with hunting bags also expanded significantly (raccoon: 2.00 → 9.60 UTM cells/year; raccoon dog: 5.80 → 15.20 UTM cells/year). These trends and the size of potentially suitable habitats suggest a further spread and population increase, posing challenges for nature conservationists and wildlife managers. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Social Impact Statement Gingko biloba is an iconic tree with a surprising connection to the SARS and Covid viruses that have impacted human health since 2003. Natural history studies on the ecology of Gingko seed dispersal by Carnivoran scavengers in Asia over the past 30 plus years have elucidated the deep evolutionary history that not only makes these animals effective at spreading seeds but also predisposes them to become intermediate hosts for spreading diseases to humans. Understanding the behavioral traits that underlie these kinds of plant–animal interactions has the potential to help people limit the spread of future spillover diseases. Summary Raccoon dogs and masked palm civets are Carnivoran scavengers native to Eastern Asia that have been documented feeding on the malodorous sarcotesta of Ginkgo biloba seeds and effectively dispersing the hard nuts they contain. Research has shown that their immune systems are genetically enhanced to protect them from the disease‐causing organisms they might pick up from their omnivorous diets that include live and dead animals. Both species are farmed for fur and meat across China and, up until recently, were commonly sold in “wet” markets. Research has determined that the palm civet played a role in spreading the SARS virus to humans in 2003 and that the raccoon dog may have played a similar role in spreading Covid in Wuhan in 2019, although this has not been proven. In areas where Ginkgo is cultivated, there are numerous internet reports of Carnivorans feeding on its seeds indicating that its dispersal strategy of attracting scavengers by mimicking the smell of carrion is adaptive and effective.

Rabies is a zoonotic viral disease of all warm-blooded animals caused by a neurotropic virus, member of the Lyssavirus genus of the Rhabdoviridae family. About 59,000 people die from hydrophobia globally every year. According to the World Health Organization, the red fox (Vulpes vulpes) and the common raccoon dog (Nyctereutes procyonoides) are the main reservoirs and vectors among carnivores of the rabies virus in Europe. The paper describes animal rabies situation in 2011–2023 and the role of oral vaccination of wild carnivores against rabies in the Moscow Oblast. The region is a part of the Central Federal District and located in the center of the Russian plain bordering seven Oblasts (Tver, Smolensk, Kaluga, Tula, Ryazan, Vladimir and Yaroslavl Oblasts), which are also rabies infected. Notwithstanding the metropolis growth, the number of wild carnivores in the Moscow Oblast remains high. Comprehensive preventive measures to control the population of the wild carnivores are taken to stabilize the rabies situation and decrease the incidence, innovative achievements in laboratory diagnosis are introduced, population immunity of wild carnivores by oral vaccination is improved and the epidemic situation in neighboring regions is analyzed. In 2017 the systemic, consistent and thoroughly organized campaign was started – the oral vaccines were distributed by light aircrafts. The research revealed the correlation between the decrease in annual number of reported rabies cases and increase in the amounts of oral vaccines distributed. The use of controlling devices (camera traps) confirmed that oral rabies vaccines are consumed by the target animals (red foxes). The onward systemic, methodical approach to rabies prevention will mitigate the risks of rabies occurrence in the Moscow Oblast.

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. [ABSTRACT FROM AUTHOR]

Introduction: Intrapulmonary arteriovenous anastomoses (IPAVAs) are defined as relatively large, dynamic shunt vessels that connect the pulmonary arterial and venous systems, thereby bypassing the pulmonary capillary system. IPAVAs lower elevated pulmonary arterial pressure; however, the presence of the shunt can result in impaired pulmonary gas exchange and paradoxical embolism. Furthermore, the prevalence and effects of IPAVAs in raccoon dogs remain unknown. This study aimed to determine the prevalence of IPAVA among rescued Korean raccoon dogs and evaluate the changes in IPAVA following oxygen supplementation. Methods: Nineteen raccoon dogs rescued by the Jeonbuk Wildlife Centre between August 2022 and December 2023 were subjected to echocardiography. Sixteen healthy and three abnormal raccoon dogs were subjected to transthoracic agitated saline contrast echocardiography (bubble study) based on the echocardiography results. IPAVA was considered to be present if the left heart contrast was visualised after four cardiac cycles following the visualisation of the first right heart contrast. Bubble scores (BS0-5) were assigned based on the maximum number of microbubbles observed in the left ventricular lumen per frame of the ultrasound image. BS was assigned before and after supplementation with 100% oxygen for 5 min. Results: IPAVA was detected in 12 of the 16 healthy raccoon dogs at rest (75%). The BS of the 15 IPAVA-positive raccoon dogs ranged from 1 to 4 points (BS1, 1; BS2, 4; BS3, 8; and BS4, 2). Blood flow through the IPAVA (QIPAVA) was reduced or absent in the 15 IPAVA-positive raccoon dogs after supplementation with 100% oxygen (BS0, 11; BS2, 4). Moreover, BS of the IPAVA showed a significant correlation with the cardiac output per body weight (BW). Conclusion: The prevalence of IPAVA in healthy raccoon dogs at rest was 75%. Adequate oxygen supplementation was found to be effective in reducing QIPAVA, which may help prevent potential negative factors such as pulmonary gas exchange impairments and paradoxical embolismthat can occur with IPAVA. [ABSTRACT FROM AUTHOR]

Various domestic and wildlife species have been found susceptible to and infected with SARS‐CoV‐2, the causative agent of COVID‐19, around the globe, raising concerns about virus adaptation and transmission to new animal hosts. The virus circulation in the white‐tailed deer population in North America has further called to action for virus surveillance in the wildlife. Here, we report on the first SARS‐CoV‐2 survey of wild animals in Japan, where frequent wildlife invasions of urban areas have occurred due to the limited predation, field abandonment, the increase of human acclimatization. Genetic testing using nasal swabs and serological screening have been conducted for sika deer, brown bears, raccoons, and raccoon dogs captured in Hokkaido prefecture from the end of the Delta variant wave to the spread of the Omicron variant, between March 2022 and February 2023. No viral RNA was detected in raccoons (0/184), sika deer (0/107), and brown bears (0/14) indicating that the virus was unlikely to spread within the population of these animal species. Among 171 raccoons, 20 raccoon dogs, 100 sika deer, and 13 brown bears, one raccoon, one brown bear, and two deer tested positive in the antibodies screening with multispecies SARS‐CoV‐2 N‐protein ELISA. Still, ELISA‐positive samples tested negative in three other serological tests, emphasizing the importance of confirming serological screening results. Our results suggested that SARS‐CoV‐2 was unlikely to spillback from humans to wildlife in Hokkaido during the study period, with the emergence of new variants, continuous surveillance is of utmost importance. [ABSTRACT FROM AUTHOR]

The Nyctereutes procyonoides is highly regarded in the farming and leather industries because of the high value of its fur, which renders artificial feeding a crucial aspect. However, high-fat diets have always been associated with a variety of digestive disorders. This study aimed to investigate the impact of high-fat diets on the gut microbiota and the mechanisms of gut damage in Nyctereutes procyonoides. 16S rRNA sequencing demonstrated that high-fat diets caused diarrhea and intestinal damage through alterations in the gut microbiota: a decrease in the abundance of Firmicutes, an increase in the abundance of Proteobacteria and Actinobacteria, and an increase in the abundance of Enterococcaceae, Escherichia coli-Shigella, Clostridium and Lactobacillus. Subsequently, changes in metabolic pathways, such as amino and fatty acid pathways, were identified by KEGG and COG enrichment analysis, and the TLR4/NF-κB/NLRP3 inflammatory signaling pathway was shown to be activated by high-fat diets. In addition, high-fat diets lead to the accumulation of ROS and MDA and reduce the activity of the antioxidant enzymes GSH-PX and SOD. Correspondingly, the levels of proinflammatory cytokines (IL-6, IL-1β and TNF-α) were significantly increased, and the apoptosis and necrosis signaling pathways of colonic cells were detected, causing a dramatic decrease in the expression of intestinal tight junction proteins (Occludin, E-cadherin, ZO-1 and ZO-2). In conclusion, high-fat diets altered the structure of the Nyctereutes procyonoides gut microbiota community and led to colon damage. This study provides new insights into the intestinal health of Nyctereutes procyonoides. Highlights: 1. High-fat diets result in disruption of Nyctereutes procyonoides intestinal flora. 2. High-fat diets cause functional and metabolic disturbances in the intestinal flora. 3. Disorders of gut microbiota induce inflammatory response, oxidative stress, and intestinal barrier disruption in the Nyctereutes procyonoides colon. [ABSTRACT FROM AUTHOR]

Whether an invasive species thrives in cold ecosystems depends on its response to winter weather. A potential threat to these ecosystems in Europe is the invasive raccoon dog (Nyctereutes procyonoides). The survival of this mesopredator is supported in cold weather, because it can periodically use winter sleep, but its winter activity levels compared to native mesopredators remain unclear. We investigated the winter behaviour of raccoon dogs in Finland, near the edge of their invasion front, and compared their activity to native red foxes and badgers. Using wildlife cameras, we found that raccoon dogs do reduce activity during the coldest months, but camera observations did not strongly correlate with temperature perhaps due to feeding at camera sites. That is, artificial food sources may have increased raccoon dogs' winter activity. Nevertheless, they responded more clearly to temperature drops than red foxes, but were more active than badgers that were mostly dormant and thus absent from our data. GPS-tracked raccoon dogs remained at some level active through winter, even near subarctic regions, but the cold and snowy weather clearly decreased activity and individuals stayed close to their nests during the coldest periods. Overall, these findings suggest that raccoon dogs can maintain some winter activity even in extremely cold environments, and they readily exploit human-provided resources. This potential ability to thrive in cold regions highlights the invasive potential of raccoon dogs. As winters become milder due to climate change, their numbers could increase significantly within cold-adapted ecosystems, impacting native species and posing conservation challenges. [ABSTRACT FROM AUTHOR]

The Asiatic raccoon dog (Nyctereutes procyonoides) has successfully colonized Northern, Eastern, and Central Europe, following 20th century introductions. While subject to eradication campaigns, its ecological impacts remain incompletely understood and debated. This study aims to examine the habitat preference and movement patterns of raccoon dogs in Denmark using GPS telemetry data. Habitat selection patterns were examined seasonally using Jacob's electivity index. Movement intensity (travel speed) was examined according to temporal and environmental predictors such as time of day, time of year and habitat type. Raccoon dogs showed an overall preference for peatbogs, marshes, and broadleaf tree cover, and an overall avoidance of water bodies (per se), artificial surfaces and constructions, natural material surfaces (e.g., river pebble banks, beaches, sand dunes), cultivated areas, coniferous tree cover and herbaceous vegetation, and a close to neutral selection pattern for moors and heathland. Habitat usage was generally consistent throughout the seasons for all habitat types, apart from minor shifts observed, particularly from November to February. The raccoon dog exhibited a unimodal nocturnal activity pattern throughout all seasons, with highest mean travel speeds occurring during spring and lowest during winter. Prolonged periods of higher mean daily speeds were observed during autumn. Mean speed levels also varied according to habitat type, with raccoon dogs moving slower in habitats they preferred and faster in those they did not prefer. These results indicate that raccoon dogs in Denmark adjust their habitat selection and movement patterns throughout the year, with a general preference for moist and high tree coverage areas. This information can be utilized in forecasting models for their potential future range and area use in different regions. [ABSTRACT FROM AUTHOR]

Introduction: Nyctereutes procyonoides koreensis (Korean raccoon dog), a member of the Canidae family, is anatomically similar to dogs. Previous studies have used vertebral heart scale measurements to measure the cardiac size of Korean raccoon dogs on thoracic radiographs; however, the use of additional cardiac size indices, such as vertebral left arial score, intercostal space, cardiothoracic ratio, and echocardiographic indices, has not been reported. Therefore, this study aimed to establish normal reference ranges for various thoracic radiographic and echocardiographic indices in normal Korean raccoon dogs. Methods: Twenty-six Korean raccoon dogs (11 males and 15 females) were included in this study. The thoracic radiographic indices, vertebral heart scale score, and vertebral left atrial score were measured in the right lateral view. The intercostal space and cardiothoracic ratio were measured in the ventrodorsal view. The echocardiograms were evaluated in the right parasternal long and short axis view and left parasternal apical view. Results: The mean values for the thoracic radiographic and echocardiographic indices were as follows: vertebral heart scale, 9.12 ± 0.74; vertebral left atrial score, 1.5 ± 0.31; intercostal spaces, 3.17 ± 0.34; cardiothoracic ratio, 0.69 ± 0.07; left atrial to aortic root ratio, 1.22 ± 0.14; main pulmonary artery to aorta ratio, 1.22 ± 0.14; left ventricular end-diastolic internal diameter normalized for body weight, 1.36 ± 0.19; end-diastolic volume index, 51.07 ± 19.6; end-systolic volume index, 16.54 ± 7.45; the peak velocity of early diastolic transmitral flow, 73.13 ± 15.46 cm/s; and the ratio between the transmitral flow velocities and the peak early diastolic velocity, 1.77 ± 0.47. Only percent increase in the left ventricular end-systolic internal diameter was negatively correlated with body weight. The remaining indices showed no correlations with body weight. Conclusion: To the best of our knowledge, this is the first case report covering both thoracic radiographic and endocardiographic indices for Korean raccoon dogs. Thus, the thoracic radiographic and echocardiographic indices established in this study may be used to evaluate the cardiac condition of Korean raccoon dogs. [ABSTRACT FROM AUTHOR]

Camera traps have been widely used in wildlife research, offering significant potential for monitoring species interactions at ephemeral resources. However, raw data obtained from camera traps often face limitations due to observation censoring, where resource consumption by dominant animals may obscure potential resource use by less dominant animals. We extended time‐to‐detection occupancy modeling to quantify interspecific consumptive competition and redundancy of ecosystem functions through consumption between two species, while accounting for observation censoring. By treating resource use by rival species as censored data, we estimated the proportion of resources potentially used in the absence of rival species and calculated the loss caused by the rival species, which is defined as "Competition Intensity Index." We also defined the Unique Functional Contribution, which represents the net functional loss when a species is removed, calculated by excluding the contribution potentially substituted by the other species. We also considered resource degradation and computed the quantity of resources acquired by each species. This established framework was applied to predation data on bird nests by alien squirrels and other predators (Case 1) as well as scavenging on mammalian carcasses by two carnivores (Case 2). In Case 1, the introduction of squirrels significantly affected the breeding success of birds. Although nests were being preyed upon by native crows also, our model estimated that Unique Functional Contribution by the squirrels was 0.47. This means that, by eradicating the squirrels, the reproductive success of the birds could potentially increase by as much as 47%. In Case 2, the Competition Intensity Index for foxes was 0.17, whereas that for raccoon dogs was 0.46, suggesting an asymmetric effect of resource competition between the two species. The frequency distribution of wet mass available to the two species differed significantly. This approach will enable a more robust construction of resource–consumer interaction networks. [ABSTRACT FROM AUTHOR]

Background: Sarcocystis includes a global group of apicomplexan parasites with two-host life cycle frequently circulating in wildlife and domestic hosts, including humans. Two of the most important wild terrestrial carnivores acting as definitive hosts are the red fox and raccoon dog, due to their wide distribution in Europe and usage of wild and farmed animals as prey. This study was conducted to determine the prevalence of Sarcocystis in hunted red foxes and raccoon dogs from nine regions of the Czech Republic and to identify isolated sporocysts by molecular techniques. Methods: Approximately 5 g of the contents of large intestine from 200 animals (197 red foxes and three raccoon dogs) were examined by flotation centrifugation coprological method. Only samples of 50 red foxes and one raccoon dog positive to Sarcocystis spp. were used for the nested PCR (nPCR) method to amplify a fragment or partial sequence on the cox1 gene. Ten species-specific primer pairs for detection of Sarcocystis spp. using farm animals as intermediate hosts were utilized. Results: In total, 38.1% of the red foxes and 66.7% of the raccoon dogs were positive to Sarcocystis by light microscopy. The molecular characterization resulted in the identification of five species in the red fox: S. arieticanis, S. capracanis, S. cruzi, S. miescheriana, and S. tenella, while the PCR was negative for the sole raccoon dog. The highest intraspecific variation was found for S. miescheriana, while S. tenella was the most prevalent. Co-infections occurred in the large intestine of the red fox. No zoonotic species were found in our samples. Conclusion: This is the first study where the potential role of the red fox and raccoon dogs as spreaders of Sarcocystis to farm animals in the Czech Republic is shown. The use of species-specific primers provides a fast and easy method for screening multiple samples for a particular Sarcocystis species. [ABSTRACT FROM AUTHOR]

In this study, we investigated faecal specimens from legally hunted and road‐killed red foxes, raccoons, raccoon dogs, badgers and martens in Germany for parasites and selected zoonotic bacteria. We found that Baylisascaris procyonis, a zoonotic parasite of raccoons, had spread to northeastern Germany, an area previously presumed to be free of this parasite. We detected various pathogenic bacterial species from the genera Listeria, Clostridium (including baratii), Yersinia and Salmonella, which were analysed using whole‐genome sequencing. One isolate of Yersinia enterocolitica contained a virulence plasmid. The Salmonella Cholerasuis isolate encoded an aminoglycoside resistance gene and a parC point mutation, conferring resistance to ciprofloxacin. We also found tetracycline resistance genes in Paeniclostridium sordellii and Clostridium baratii. Phylogenetic analyses revealed that the isolates were polyclonal, indicating the absence of specific wildlife‐adapted clones. Predators, which scavenge from various sources including human settlements, acquire and spread zoonotic pathogens. Therefore, their role should not be overlooked in the One Health context. [ABSTRACT FROM AUTHOR]

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The impact of infectious diseases on host populations is often not quantified because it is difficult to observe the host population and infectious disease dynamics. To address this problem, we developed a state-space model to simultaneously estimate host population and disease dynamics using wildlife rescue data. Using this model, we aimed to quantify the impact of sarcoptic mange on a Japanese raccoon dog population by estimating the change in their relative population size. We classified the status of rescued raccoon dogs into four categories: i) rescued due to infection with mange, ii) rescued due to traffic accidents without mange, iii) rescued due to traffic accidents with mange, and iv) rescued due to causes other than traffic accidents or mange. We modelled the observation process for each category and fitted the model to the reported number of raccoon dogs rescued between 1990 and 2010 at three wildlife rescue facilities in Kanagawa Prefecture, Japan. The mortality rate induced by mange was estimated to be 1.09 (95% credible interval (CI): 0.47–1.72) per year. The estimated prevalence of sarcoptic mange ranged between 4 and 80% in the study period. When a substantial prevalence of mange was observed (1995–2002), the host population size decreased by 91.2% (95% credible intervals: 86.3–94.7). We show that the impact of infectious disease outbreak on the wildlife population can be estimated from the time-series data of wildlife rescue events due to multiple causes. Our estimates suggest that sarcoptic mange triggered a substantial decrease in the Japanese wild raccoon dog populations.

Simple Summary: This study shows that automated computer vision techniques are highly effective when used to analyze images and to extract valuable information from them. We trained an algorithm with a set of 1600 images obtained from a study where wildlife approaching wild boar carcasses were monitored. This enabled the model to detect different classes of animals automatically in their natural environment with a mean average precision of 98.11%. Camera traps are becoming widely used for wildlife monitoring and management. However, manual analysis of the resulting image sets is labor-intensive, time-consuming and costly. This study shows that automated computer vision techniques can be extremely helpful in this regard, as they can rapidly and automatically extract valuable information from the images. Specific training with a set of 1600 images obtained from a study where wild animals approaching wild boar carcasses were monitored enabled the model to detect five different classes of animals automatically in their natural environment with a mean average precision of 98.11%, namely 'wild boar', 'fox', 'raccoon dog', 'deer' and 'bird'. In addition, sequences of images were automatically analyzed and the number of wild boar visits and respective group sizes were determined. This study may help to improve and speed up the monitoring of the potential spread of African swine fever virus in areas where wild boar are affected. [ABSTRACT FROM AUTHOR]

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. Author summary: Raccoon dogs are thought to have been a crucial link in the chain that led to the spread of the COVID-19 virus to humans. The key to a coronavirus moving from one species to another is its spike protein's ability to bind to receptors on the cells of the new host. In our research, we investigated the interaction between the spike protein of the COVID-19 virus and the ACE2 receptor in raccoon dogs, using both structural and biochemical techniques. We found that the ACE2 receptor in raccoon dogs does indeed work as an effective receptor for the virus, but there are critical differences when compared to the human ACE2 receptor, which may act as barriers to the virus making the jump between raccoon dogs and humans. To our knowledge, this study is the first in-depth examination of these cross-species transmission barriers for the COVID-19 virus, shedding light on how other mammals might be impacted by the virus. Our findings indicate that raccoon dogs could potentially carry and pass the COVID-19 virus on to humans, providing foundational knowledge for how the virus can navigate between different species. [ABSTRACT FROM AUTHOR]

The western population of the red‐crowned crane Grus japonensis in mainland China has been decreasing in the past few decades and wild population enhancement programmes have been launched in this country. First, 14 captive‐bred red‐crowned cranes were released into the core area of Yancheng National Nature Reserve for Rare Birds (YNNR), one of the most important wintering areas of this species, in 2013 (seven individuals) and 2015 (seven individuals) and then 8 more captive‐bred cranes were released into YNNR from February 2022 to February 2023. We used satellite positioning and drone monitoring to study the status of released cranes. The results showed that two individuals (No. BJZ001 and BJZ008) from the first group of released cranes were found breeding in 6 of 7 years in the YNNR from 2017 to 2023. Three individuals (No. WNNR022, WNNR025 and WNNR026) from the second group of released cranes were recorded breeding in YNNR in 2023. All released cranes lived in the YNNR year round and did not migrate with wild cranes. Raccoon dogs, Nyctereutes procyonoides, were first recorded as red‐crowned crane nest predators in the YNNR. Although these released cranes breed successfully in the YNNR, nestlings might face the threat of predators in non‐traditional breeding areas. Further research is needed to determine whether offsprings of released individuals migrate with wild cranes and if breeding in their original wintering grounds is truly beneficial for population growth. [ABSTRACT FROM AUTHOR]

Many different animal species are susceptible to SARS-CoV-2, including a few Canidae (domestic dog and raccoon dog). So far, only experimental evidence is available concerning SARS-CoV-2 infections in red foxes (Vulpes vulpes). This is the first report of SARS-CoV-2 RNA detection in a sample from a red fox. The RT-qPCR-positive fox was zoo-kept together with another fox and two bears in the Swiss Canton of Zurich. Combined material from a conjunctival and nasal swab collected for canine distemper virus diagnostics tested positive for SARS-CoV-2 RNA with Ct values of 36.9 (E gene assay) and 35.7 (RdRp gene assay). The sample was analysed for SARS-CoV-2 within a research project testing residual routine diagnostic samples from different animal species submitted between spring 2020 and December 2022 to improve knowledge on SARS-CoV-2 infections within different animal species and investigate their potential role in a One Health context. Within this project, 246 samples from 153 different animals from Swiss zoos and other wild animal species all tested SARS-CoV-2 RT-qPCR and/or serologically negative so far, except for the reported fox. The source of SARS-CoV-2 in the fox is unknown. The fox disappeared within the naturally structured enclosure, and the cadaver was not found. No further control measures were undertaken. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Raccoon dogs (Nyctereutes procyonoides) and raccoons (Procyon lotor) are invasive alien species originating from East Asia and North America, respectively. They are discussed as vectors and reservoirs for various infectious diseases, including vector-borne and zoonotic pathogens, and are therefore a potential threat to human and domestic animal health, as well as to biodiversity and conservation. In the years 2021 and 2022, 110 raccoon dogs (Nyctereutes procyonoides) and 30 raccoons (Procyon lotor) were screened via qPCR for the presence of Leptospira spp., Rickettsia spp. and Borreliella spp. in the German federal state of Schleswig-Holstein as part of a health and risk assessment study. Borreliella spp. were confirmed in one raccoon dog and one raccoon, identified as Borreliella afzelii in the raccoon. Leptospira spp. were found in 21 (19.44%) raccoon dogs and 2 (6.90%) raccoons. In five raccoon dogs, Leptospira spp. were identified as Leptospira borgpetersenii, Leptospira kirschneri and Leptospira interrogans. [ABSTRACT FROM AUTHOR]

The intracellular protozoan Toxoplasma gondii is distributed worldwide and infects many species of warm-blooded animals. Most mammals, including humans, can serve as intermediate hosts. This pathogen, with its zoonotic potential, causes toxoplasmosis, a condition that can range from subclinical to fatal in humans. It is therefore important to assess the occurrence of the pathogen, even if only indirectly through the detection of antibodies. Epidemiological data on the seroprevalence in wild animals, including invasive species, are rare in Poland. Therefore, we tested 197 wild raccoons (Procyon lotor) and 89 raccoon dogs (Nyctereutes procyonoides) from Zgorzelec County, southwestern Poland, for the presence of antibodies. Samples were collected between January 2019 and December 2020 and analysed using a commercial indirect modified agglutination test (MAT, cut-off 1:25). The statistical analysis revealed significant differences in seroprevalence between the two predatory species. Of the 197 surveyed raccoons, 96 (48.73%; 95% confidence interval (CI): 41.73–55.73%) tested positive, while 25 of the 89 raccoon dogs (28.09%; 95% CI: 18.70–37.48%) were positive. Regarding risk factors, body weight and sex influenced the presence of T. gondii antibodies in both the species, with a higher likelihood of seropositivity among heavier animals and females, respectively. For raccoon dogs, juveniles were more likely to be seropositive than adults at a given weight. Our results suggest that T. gondii infection is widespread in the regional raccoon and raccoon dog populations, indicating a high level of parasite circulation in the environment. [ABSTRACT FROM AUTHOR]

BackgroundSarcocystis includes a global group of apicomplexan parasites with two-host life cycle frequently circulating in wildlife and domestic hosts, including humans. Two of the most important wild terrestrial carnivores acting as definitive hosts are the red fox and raccoon dog, due to their wide distribution in Europe and usage of wild and farmed animals as prey. This study was conducted to determine the prevalence of Sarcocystis in hunted red foxes and raccoon dogs from nine regions of the Czech Republic and to identify isolated sporocysts by molecular techniques.MethodsApproximately 5 g of the contents of large intestine from 200 animals (197 red foxes and three raccoon dogs) were examined by flotation centrifugation coprological method. Only samples of 50 red foxes and one raccoon dog positive to Sarcocystis spp. were used for the nested PCR (nPCR) method to amplify a fragment or partial sequence on the cox1 gene. Ten species-specific primer pairs for detection of Sarcocystis spp. using farm animals as intermediate hosts were utilized.ResultsIn total, 38.1% of the red foxes and 66.7% of the raccoon dogs were positive to Sarcocystis by light microscopy. The molecular characterization resulted in the identification of five species in the red fox: S. arieticanis, S. capracanis, S. cruzi, S. miescheriana, and S. tenella, while the PCR was negative for the sole raccoon dog. The highest intraspecific variation was found for S. miescheriana, while S. tenella was the most prevalent. Co-infections occurred in the large intestine of the red fox. No zoonotic species were found in our samples.ConclusionThis is the first study where the potential role of the red fox and raccoon dogs as spreaders of Sarcocystis to farm animals in the Czech Republic is shown. The use of species-specific primers provides a fast and easy method for screening multiple samples for a particular Sarcocystis species.

Cover image: A raccoon dog roaming in Shanghai urban environment. People's familiarity with raccoon dogs positively influenced their tolerance. Education programs that familiarize the public with raccoon dogs as well as other species, which can turn urban human‐wildlife conflicts into harmonious relationships in Shanghai and potentially other urban areas. Photo by Xiaodong Sun.. [Extracted from the article]

Originally from Asia, the raccoon dog Nyctereutes procyonoides is an invasive alien species in Europe, listed since 2019 on the List of invasive alien species of Union concern. The raccoon dog is considered to have negative impact on native biodiversity, as well as a crucial role in hosting and transmitting diverse parasites and pathogens of human and veterinary importance. In the present study, stomach content analyses and parasitological examinations were performed on 73 raccoon dogs from Germany. In addition, fecal samples were analyzed. The results of the study confirm the assumption that the examined raccoon dogs were infested with a various ecto- and endoparasite fauna. A total of 9 ecto- and 11 endoparasites were detected, with 6 of the endoparasites having human pathogenic potential. Trichodectes canis (P = 53.42%), Toxocara canis (P = 50.68%) and Uncinaria stenocephala (P = 68.49%) were the most abundant parasite species. The stomach contents consisted of approximately one-third vegetable and two-thirds animal components, composed of various species of amphibians, fish, insects, mammals and birds. Among them were specially protected or endangered species such as the grass frog Rana temporaria. The study shows that the raccoon dog exerts predation pressure on native species due to its omnivorous diet and, as a carrier of various parasites, poses a potential risk of infection to wild, domestic and farm animals and humans.

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. Genderspecific 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. [ABSTRACT FROM AUTHOR]

Simple Summary: Raccoon dogs are typically omnivorous and exhibit a diverse dietary range, encompassing small mammals as well as plant matter, which underscores their high adaptability and renders them particularly intriguing subjects for study. Alfalfa meal, renowned for its superior nutritional composition, is employed as a high-quality feed ingredient for ruminants. Diet represents an important determinant influencing the intestinal microbiota. In this study, raccoon dogs were fed diets containing alfalfa meal to scrutinize alterations in their intestinal microbiota. The results showed that supplementation with appropriate alfalfa meal could enhance intestinal health without affecting the growth and overall health of raccoon dogs. This research indicates that raccoon dogs possess a certain tolerance to supplementation with alfalfa meal, thus confirming their ability to tolerate rough feeding. The raccoon dog (Nyctereutes procyonoides) is a typical omnivore possessing wide dietary adaptability and tolerance to rough feeding, which may be attributed to its intestinal microbiota. The study aimed to investigate the effect of dietary alfalfa meal levels on the growth performance, nutrient apparent digestibility, serum parameters, and intestinal microbiota of raccoon dogs. Sixty raccoon dogs were randomly divided into four dietary treatments containing 0% (AM0), 5% (AM5), 10% (AM10), and 15% (AM15) alfalfa meal for a 60-day experiment. The results showed that compared to raccoon dogs fed the AM0 diet, those fed the AM5 and AM10 diets had no significant difference in growth performance, while those fed the AM15 diet experienced a significant decrease. Raccoon dogs fed the AM5 diet had no significant effect on the nutrient apparent digestibility. Dietary supplementation with alfalfa meal significantly decreased serum urea levels and increased the antioxidant capacity of raccoon dogs. The intestinal microbiome analysis showed that the richness and diversity of colonic microbiota significantly increased in the AM15 group. With the increase in dietary alfalfa meal levels, the relative abundance of fiber-degrading bacteria in the colon of raccoon dogs, such as Treponema, Phascolarctobacterium, and Christensenellaceae R-7 group, increased. However, the relative abundance of pathogenic bacteria, including Anaerobiospirillum, decreased. In conclusion, the inclusion of 5% alfalfa meal in the raccoon dogs' diet had no effect on growth performance, but it exhibited the potential to improve serum antioxidant capacity and intestinal microbiota. This indicates that raccoon dogs have a certain tolerance to the addition of alfalfa meal in their diet. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

It is possible and risky for fur animal carcasses to be mixed into meat products, which is a potential danger for meat quality safety and human health. Therefore, meat validation of quality and constituents is crucial. A variety of methods have been developed to identify muscle tissues of different species. However, most of these methods have the disadvantages of poor repeatability, complex operation and low efficiency, and cannot simultaneously detect multiple species of muscle tissue. The purpose of this study was to construct a multiplex PCR protocol to detect the samples of mink, fox, and raccoon dog. In this study, the specific primers of mink, fox, and raccoon dog were designed according to the variable region sequence of mitochondrial cytochrome b (Cytb) gene. The primers showed good specificity and 50 ℃ was determined as the optimal annealing temperature. The lowest concentration of DNA template of mink, fox, or raccoon dog that could be determined simultaneously by a single tube was 1 pg/µL. Clinical tissue samples detect analysis test results showed that this method could identify whether the tissue samples of three fur animals were mixed from the muscles of chickens, ducks, dogs, cattle, sheep, pigs and rabbits in one PCR reaction simultaneously. In conclusion, the scheme exhibited the advantages of convenient operation, low cost, strong species specificity, high sensitivity, good stability, and repeatability. The systematic optimized inspection process can be applied to meat detection to ensure veterinary public health safety, which has important scientific significance, production, public health, and safety significance. [ABSTRACT FROM AUTHOR]

Human alveolar echinococcosis (AE) is a serious parasitic disease caused by larval stages of Echinococcus multilocularis. Between January 2000 and October 2023, 137 AE cases were confirmed in Slovakia. The average annual incidence increased from 0.031 per 100,000 inhabitants between 2000 and 2011, to an average of 0.187 since 2012, i.e. about six times. Among patients, 45.3% were men and 54.7% were women; the mean age at the time of diagnosis was 52.8 years. Most cases were diagnosed in the age groups 51–60 years and 61–70 years (33 cases each), and eight patients fell into the age category ≤ 20 years. To better recognize the gene diversity in clinical samples, metacestodes from 21 patients collected between 2013 and 2021 were subjected to DNA sequencing of four mitochondrial genes. Using concatenated sequences of cob (603 bp), nad2 (882 bp) and cox1 (789 bp) gene fragments, 14 isolates (66.7%) were assigned to the European E5 profile of E. multilocularis, two isolates (9.5%) to the E5a subtype, four isolates (19%) to the E4 profile, and one isolate (4.8%) to haplogroup E1/E2. The E5-type profiles and E4 profiles were distributed throughout the country, whereas the E1/E2 profile was found in the patient from western Slovakia. According to the data obtained and GenBank sequences, the E5-type dispersal is so far limited to central-eastern Europe and the variant seems to be indigenous to that region. The admixture with the haplotypes E4 and E1/E2 could have taken place from a historical endemic focus during the fox expansion in the last decades. By employing the nad1 fragment, a typical European haplotype was observed in all 21 resolved Slovak samples. The acceleration in the AE incidence in the last decade suggests the emergence of the disease and the need for further research on human and animal isolates. Author summary: Human alveolar echinococcosis (AE) is a serious parasitic disease that may lead to death within 10–15 years after diagnosis if untreated. It is caused by larval stages of the fox tapeworm, Echinococcus multilocularis, which predominantly circulates in the sylvatic cycle, with carnivores (foxes, raccoon dogs, jackals, wolves) as definitive hosts and small mammals as intermediate hosts. Human infection occurs after the accidental ingestion of infective parasite eggs. The liver is the most often affected organ, and the parasite shows features similar to malignant tumors with invasive and infiltrative growth and metastasis formation. Here we present current epidemiological data on human alveolar echinococcosis in Slovakia and compare the geographical distribution of AE cases with occurrence of parasite in red foxes. Moreover, the genetic diversity of E. multilocularis is not yet fully understood, and it is supposed that even subtle genetic differences may have relevance for variation in infectivity for humans. Therefore, we addressed the question of distribution of E. multilocularis haplotypes in clinical isolates across the country and investigated their genetic relatedness with haplotypes in other countries of Europe. [ABSTRACT FROM AUTHOR]

Background: Ussuri raccoon dog is an important economic animal, which brings considerable economic benefits to Hebei, China. The high fertility rate of Ussuri raccoon dog is vital for its breeding industry. However, the molecular mechanism of prolificacy traits in raccoon dog remains unclear. Therefore, it is of great importance to identify the related genes and analyze the genetic mechanism of its high reproductive traits. Methods: In our study, RNA-seq was performed using ovarian tissues from six Ussuri raccoon dogs during estrus. The samples were divided into two groups based on the litter size over the last three consecutive years. We performed a standard transcriptomic analysis procedure to dig for differentially expressed genes (DEGs) and analyze gene function in detail. Result: Statistical analysis revealed a total of 612 DEGs between the low-fecundity and high-fecundity group including 277 upregulated and 335 downregulated DEGs, respectively. KEGG pathway analysis shows the DEGs enriched in several reproductive related pathways, such as the Circadian entrainment pathway. A total of 8 DEGs were identified with differential alternative splicing (DAS) events and recognized as DAS-DE genes. Among the up-regulated DAS-DE genes, ABCA6 and GPAM were found to be the most important genes regulating the prolificacy trait of Ussuri raccoon dog. The DEGs and DAS-DE genes identified in this study provide a probable genetic mechanism for improving prolificacy of Ussuri raccoon dog breeding. [ABSTRACT FROM AUTHOR]

Originally from Asia, the raccoon dog Nyctereutes procyonoides is an invasive alien species in Europe, listed since 2019 on the List of invasive alien species of Union concern. The raccoon dog is considered to have negative impact on native biodiversity, as well as a crucial role in hosting and transmitting diverse parasites and pathogens of human and veterinary importance. In the present study, stomach content analyses and parasitological examinations were performed on 73 raccoon dogs from Germany. In addition, fecal samples were analyzed. The results of the study confirm the assumption that the examined raccoon dogs were infested with a various ecto- and endoparasite fauna. A total of 9 ecto- and 11 endoparasites were detected, with 6 of the endoparasites having human pathogenic potential. Trichodectes canis (P = 53.42%), Toxocara canis (P = 50.68%) and Uncinaria stenocephala (P = 68.49%) were the most abundant parasite species. The stomach contents consisted of approximately one-third vegetable and two-thirds animal components, composed of various species of amphibians, fish, insects, mammals and birds. Among them were specially protected or endangered species such as the grass frog Rana temporaria. The study shows that the raccoon dog exerts predation pressure on native species due to its omnivorous diet and, as a carrier of various parasites, poses a potential risk of infection to wild, domestic and farm animals and humans. [Display omitted] • Stomach content analyses, parasitological and fecal examinations were performed on 73 raccoon dogs from Germany. • 9 ecto- and 11 endoparasitic species could be identified of which 6 endoparasitic species have a human pathogenic potential. • Stomach content was composed of one-third vegetable and two-thirds animal components. • Invasive alien species can have negative impact on native animal species and can act as a carrier of various parasites. [ABSTRACT FROM AUTHOR]

This work was aimed at analyzing the features of the morphology and morphometric parameters of eosinophils and their granules in the raccoon dog Nyctereutes procyonoides (Grey, 1834). Pappenheim staining of blood smears was used to determine white-blood-cell count and to assess the features of the morphology and morphometric parameters of eosinophils and their granules. Cytochemical methods were used to determine localization of cationic proteins, as well as eosinophilic peroxidase in eosinophils. ANOVA was used to assess gender effects. The study has shown that raccoon dogs are characterized by a high relative content of eosinophils (7–10% of the total population of white blood cells), as well as by the presence of large secretory granules in them. In addition to eosinophils with the typically rich cytoplasmic granularity, larger cells containing secretory granules in minor quantities and, in some cases, vacuole-like granules were present in blood smears. Gender effects manifested themselves in the higher proportion of eosinophils with a low level of cytoplasmic granularity in males compared to females, while females showed higher values of morphometric parameters (the number and mean area of granules in a single cell, as well as the ratio of the area taken by granules to the cell area). Since the causes of the appearance of eosinophils with a low content of granules, as well as with vacuolization of the cytoplasm, in raccoon dogs are not quite clear, this problem needs further investigation. [ABSTRACT FROM AUTHOR]

Sarcoptic mange was detected in five free-ranging raccoon dogs (Nyctereutes procyonoides) in the federal state of Schleswig-Holstein, Germany, during a health assessment study of invasive species, including raccoon dogs, carried out between 2021 and 2022. Four raccoon dogs showed severe lesions, including extensive alopecia with thickening and hyperpigmentation of the skin (lichenification). The fifth animal was less affected, showing only thinning of the hair coat in multiple body locations. Skin scrapings were performed and confirmed the presence of Sarcoptes scabiei. Histopathology of the skin revealed diffuse epidermal hyperplasia and hyperkeratosis, mild eosinophilic dermatitis, and varying amounts of intralesional mites. Staphylococcus pseudintermedius and Corynebacterium auriscanis were detected in the skin samples of the affected animals, indicating a secondary bacterial infection. The source of sarcoptic mange remains unclear; interspecies transmission via direct or indirect contact seems likely. Raccoon dogs are therefore a potential vector for sarcoptic mange, and their behaviour could contribute to disease spread and persistence. [ABSTRACT FROM AUTHOR]