Journal of Veterinary Medical Science最新文献

Equine rhinitis B virus (ERBV), a member of the Picornaviridae family, is associated with mild to moderate respiratory illness in horses, yet its genomic diversity remains incompletely characterized. In this study, we performed metagenomic analysis on a rectal swab sample from a diarrheic foal confirmed to be positive for rotavirus A. Unexpectedly, we identified a highly divergent ERBV strain with a 9,448-nucleotide genome encoding a 2,721-amino-acid polyprotein. Sequence analysis revealed only 62.5-63.1% identity in the polyprotein and 47.1-49.8% in the VP1 region compared to known ERBV serotypes, suggesting a novel genotype. The genome exhibited typical picornavirus features, including a type II internal ribosome entry site (IRES), but also unique elements such as an 87-amino-acid insertion in the leader proteinase region and atypical cleavage motifs. A strain-specific RT-qPCR assay was developed alongside a broadly reactive assay targeting ERBV1-3. Screening of 37 rectal swab samples from horses revealed a 10.8% positivity rate using the new assay, with clustered cases from the same farm in 2022 and an additional case in 2024. No samples were positive using the broad-range primers, indicating potential gaps in surveillance. These findings highlight the importance of metagenomics in pathogen discovery and underscore the need for updated molecular tools to monitor genetically distinct ERBV strains and assess their clinical significance.

The large Japanese field mouse, Apodemus speciosus, is a rodent species endemic to Japan and is widely distributed throughout the country. It has been extensively used as a model organism in studies of geographic isolation and as an environmental bioindicator. However, there have been no reports on the establishment of pluripotent stem cells from this species that could be applied to developmental engineering. In this study, we attempted to generate induced pluripotent stem cells (iPSCs) from A. speciosus and successfully obtained cells that formed dome-shaped colonies and expressed pluripotency markers. These cells were capable of forming embryoid bodies that expressed markers of the three germ layers, and in vivo analysis using immunodeficient mice confirmed their ability to form teratomas. A. speciosus iPSCs established in this study not only contribute to the conservation of Japan's valuable animal genetic resources, but also provide a novel platform for investigating various biological processes that remain unexplored in this wild species.

Epileptic seizures in cats and dogs are etiologically classified as idiopathic epilepsy, structural epilepsy and reactive seizures, and semiologically as atonic, tonic/clonic, or generalized tonic clonic, focal and focal seizures evolving into generalized seizures. This retrospective study aimed to evaluate the semiological patterns and etiological causes of seizures in both species, and to assess interspecies differences in a regional veterinary population. Between January 2022 and January 2025, 77 cats and 106 dogs presented with seizures to Ondokuz Mayis University Animal Hospital (Samsun/Turkiye). After exclusions due to insufficient data or financial constraints, 24 cats and 29 dogs were included based on the Tier-I diagnostic criteria proposed by the International Veterinary Epilepsy Task Force. The relationships between species, age, sex, neuter status, seizure semiology and etiology were analyzed. Generalized tonic-clonic seizures were observed in 83.3% of cats and 72.4% of dogs. Idiopathic epilepsy was diagnosed in 41.7% of cats and 55.2% of dogs. Structural epilepsy in cats was mainly associated with feline infectious peritonitis, while canine distemper virus was the predominant cause in dogs. Although seizure types were broadly similar across species, some etiological differences appeared regionally. The high rate of generalized seizures may reflect observer bias or challenges in accurately classifying semiology without electroencephalography. This study highlights the utility of tiered diagnostic approaches in veterinary epileptology and underscores the need for updated, species-specific consensus guidelines for diagnostic approach and classification especially in feline patients.

Exotic animal cafes are a growing phenomenon within Japanese cities. These cafes are registered under the same license as other animal exhibits such as zoos, often allowing visitors to directly touch the animals or interact with animals within close proximity. The aim of this research was to report on current standards of animal care found in Japanese exotic animal cafes according to animal class. We included 79 exotic animal cafes with data collected on observable husbandry and management conditions by four trained assessors. Qualifiable welfare standards under the quantifiable scores were used to support guidance in scoring methodology. Welfare categories were assessed to identify whether some animal classes received better care in exotic animal cafés. Kruskal-Wallis tests assessed differences in welfare scores across animal classes, with Bonferroni-adjusted pairwise comparisons identifying inter-class variation. Among 231 animals identified, 51% were mammals, 31% were birds and 18% were reptiles. Scores across all categories were low for all taxa assessed, with significant differences between animal classes for the environmental and nutritional provisions and the performance of natural behavior with birds scoring the lowest for all these categories. Results conclude a widespread lack of appropriate animal care provision across all facilities, resulting in poor welfare for a range of species. This study, the first comprehensive assessment of welfare standards in Japanese exotic animal cafes, concludes an urgent need for effectively enforced facility and national animal protection standards for captive exotic species in Japan.

C-reactive protein (CRP) is a key biomarker for diagnosis and prognosis in dogs. Accurate and consistent CRP measurements are essential for clinical decision-making. In Japan, different CRP measurement systems are commonly used, but their compatibility has not been validated. In this study, we evaluated the correlation and agreement among three CRP assay systems (immunonephelometry, immunoturbidimetry, and dry chemistry) using 138 dog plasma samples. Strong correlations (r >0.9) were observed, but regression analysis and Bland-Altman plots revealed systematic errors, indicating that these systems are not interchangeable. These findings highlight the need for system-specific reference ranges and clinical decision thresholds and suggest that a common calibration agent could enhance comparability and support the standardization of CRP measurements in veterinary medicine.

In 2015, the third novel virulence plasmid pVAPN of Rhodococcus equi was discovered in bovine isolate from Ireland. The first bovine case of R. equi infection in Japan was reported in 2018 at a meat inspection station in Yokkaichi, Mie Prefecture, involving a Japanese Black heifer. Subsequently, additional cases were reported through annual surveillance in Miyazaki's prefectures, Oita, Shiga, Gifu, Aichi, and Kyoto City, bringing total number of confirmed cases to 12. This review provides an overview of host-associated virulence plasmids of R. equi, a brief history of bovine R. equi case reports in Japan, and data analysis on the occurrence, clinical signs, and pathological findings of these 12 cases, along with a discussion on infection mechanisms and pathogenesis.

Extended spectrum β-lactamase producing Escherichia coli (ESBL-Ec) is recognized as an opportunistic pathogen with zoonotic potential, posing a threat to public health. This study aimed to identify virulence factor genes (VFGs), determine ESBL-Ec pathotypes and pathovars, and analyze their distribution in isolates from broiler cecum across eight Disease Investigation Center (DIC) areas in Indonesia. A total of 120 ESBL-Ec isolates were proportionally selected based on regional prevalence. The VFGs were detected using Oxford Nanopore Technologies (ONT) MinION sequencing and analyzed with bioinformatics pipelines. Of the total isolates, 113 met the quality threshold. A total of 4,269 non-redundant orthologs and alleles related to VFGs were detected, representing 99 VFG types grouped into 25 clusters, indicating substantial genetic diversity. The fim gene cluster was the most frequently detected (20.1%), whereas the esp cluster exhibited the highest allele diversity (18.2%). The VFGs encoding the ExPEC were predominant (66.7%), while the remaining VFGs encoded the InPEC (33.3%). Each isolate potentially encodes at least two pathovars, with nearly 80% encoding three or more. The diversity of VFGs and pathovar combinations highlights the disease potential and zoonotic risk of ESBL-Ec.

Pesticide poisoning in animals is a rising forensic issue due to widespread chemical use. This study analyzed stomach contents from 44 deceased animals (domestic and wild) in Japan using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS) for non-targeted screening and liquid Chromatography tandem mass spectrometry (LC-MS/MS) for quantification after Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction. Non-target screening detected multiple pesticide classes, with carbamates and herbicides being the most prevalent. Methomyl was identified in 29 cases (65.9%), with concentrations up to 157 mg/kg in cats, 75 mg/kg in a civet, and 30 mg/kg in a dog, exceeding the oral LD₅₀ of methomyl in dogs (10 mg/kg) and cats (estimated to be similar). These findings suggest acute poisoning and possible intentional misuse. The toxicological significance of methomyl highlights the need for stricter regulations, better monitoring, and increased public awareness to prevent further animal poisonings.

This study aimed to determine the effect of the timing of human chorionic gonadotropin (hCG) administration to embryo transfer (ET) recipients on the reproductive outcome of ET in crossbred beef heifers. Heifers (n=1,887) were randomly assigned to the non-treatment group (n=1,160), and hCG was administered on day 5 (n=201), 6 (n=210), 7 (n=213), or 8 (n=103) after estrus. The χ² test showed that the conception rates in the hCG administration on day 5 (79.6%, P=0.0001) and day 6 (75.2%, P=0.0047) were higher than those in the non-treatment group (65.2%). However, the conception rates with hCG administration on day 7 (70.9%, P=0.1103) and day 8 (70.9%, P=0.2499) were comparable to the non-treatment. A multiple logistic regression analysis, furthermore, showed that early treatment (hCG on day 5 or 6 after estrus) positively affected the conception rates compared to non-treatment (odds ratios (OR)=1.723 [95% confidence intervals (CI)=1.316-2.257]), but not late treatment (hCG on day 7 or 8 after estrus) (OR=1.299 [95% CI=0.981-1.719]). None of the confounding variables, including years, season at the time of ET, age in months, and number of ET, significantly affected the conception rate. In conclusion, hCG administration on day 5 or 6 after estrus for ET recipients improved the conception rate, but not on day 7 or 8, in beef heifers.

We evaluated two human diagnostic agarose gel electrophoresis (AGE) kits (J711 and J718) for bovine serum protein fractionation using 79 bovine samples, comparing the results with a biochemistry analyzer (BA). While six protein fractions were commonly observed, β₂- and γ-globulin (Glb) fusion (β₂γ-Glb) occurred in some inflammatory and neonatal cases. The results using both AGE kits correlated with those of the BA for total albumin and Glb, with J711 showing superior agreement. However, inter-kit variability was observed for individual protein fractions, particularly α₁-, α₂-, and β₁-Glb, which showed proportional or constant errors and moderate-to-poor reliability, despite good agreement for β₂γ-Glb. These findings necessitate caution in interpreting fraction-specific results and underscore the importance of stating the AGE kit in veterinary diagnostics.