Feline colorectal adenocarcinoma (FCC) is a locally invasive, highly metastatic malignant gastrointestinal tumor of colon or rectal mucosa in cats. When detected early, surgical resection may provide a promising prognosis. However, no clinical symptoms are observed in the early stages, and distant metastases or peritoneal dissemination are often already present at diagnosis. Therefore, after removal of the primary lesion, follow-up systemic therapy using anticancer drugs is required. However, the drugs currently used for FCC are not sufficiently effective in improving the prognosis, and it is necessary to develop novel and relevant preclinical models that accurately represent the disease. In this study, we developed three-dimensional culture models (organoids) from four FCC cases and examined their histopathological characteristics and drug-sensitivity profiles. FCC organoids were successfully generated and recapitulated the histological structure of the original tumor tissues. Furthermore, the FCC organoids expressed common markers (CK20 and CDX2) of FCC and exhibited tumorigenesis in vivo in mice. Cell viability assay showed that the FCC organoid lines exhibited different sensitivities to carboplatin, doxorubicin, and toceranib. Interestingly, the response of FCC organoids to toceranib varied among the lines and correlated well with the expression level of VEGFR-2, one of the target molecules of toceranib. These results suggested that FCC organoids can be used as preclinical models to advance molecular and therapeutic FCC research.

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We determined the 50% porcine infectious dose (PID₅₀) of the classical swine fever virus (CSFV) JPN/1/2018 strain currently circulating in Japan. Twelve piglets were orally inoculated with 10^1.0, 10^3.0, or 10^5.0 TCID₅₀ of the virus. All piglets receiving 10^5.0 TCID₅₀ developed typical clinical signs with viral RNA detection in their blood from 2 days post-inoculation (dpi). One piglet receiving 10^3.0 TCID₅₀ was confirmed to be infected at 4–5 dpi, while the remaining piglets in this group became infected later, with evidence of infection detected at 11–14 dpi. These results suggest that only the first infected piglet was directly infected by the viral inoculum, while the remaining 3 piglets were indirectly infected through horizontal transmission from the first infected piglet. No piglets inoculated with 10^1.0 TCID₅₀ became infected. Based on these infection patterns, the PID₅₀ was calculated as 10^3.5 TCID₅₀, providing essential data for infection risk assessment and establishing target reduction titers for disinfection against the JPN/1/2018 strain.

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The myenteric plexus morphology, which varies depending on the morphology and motility of each intestinal segment, helps us to understand the intestinal physiology, however, it has not been reported in the rabbit small intestine. We, thus, investigated the myenteric plexus morphology in the rabbit small intestine using whole-mount preparations subjected to protein gene product 9.5 immunohistochemistry. The myenteric plexus was the most well-developed in the terminal part of the ileum, followed by the cranial duodenum and distal ileum. The other segments had significantly poorly developed myenteric plexuses than the terminal part of the ileum. Findings of this study may be useful to investigate the morphology of cells in the ganglia and their roles in the mechanisms underlying intestinal motor control.

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A young female Golden Retriever with a portosystemic shunt presented with hypoalbuminemia, hyperammonemia, and severe ascites, ultimately succumbing to the illness. Necropsy revealed renal papillary necrosis in the right renal pelvis. Histological examination identified an encapsulated structure within the renal pelvis containing basophilic granules surrounded by an eosinophilic, multilayered capsule. Mass spectrometry analysis of the encapsulated structure identified predominant Staphylococcus pseudintermedius-specific proteins. This finding was further confirmed by PCR and immunohistochemistry, establishing an infection caused by Staphylococcus spp. This is the first documented case of papillary necrosis with an encapsulated structure as a severe manifestation of pyelonephritis associated with S. pseudintermedius.

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The high oxygen conditions (80% oxygen and 20% carbon dioxide) of oxygen-modified atmosphere packaging (high O₂ MAP) maintain the quality of meat. This study investigates the cultivability and viability of Campylobacter jejuni in a high O₂ MAP environment, with different strains investigated to examine whether cultivability is affected by aerotolerance. C. jejuni strains spiked chicken meat was exposed to high O₂ MAP and assessed using culture and viability-digital PCR. The results indicated suppression of the cultivability of C. jejuni under high O₂ MAP conditions, with evidence suggesting that this may not be due to aerotolerance. However, the viability of C. jejuni was not affected, indicating that bacterial cells might have been induced to a viable but non-culturable state.

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Lactate levels are critical indicators of severe, life-threatening conditions and are widely used as prognostic markers in veterinary emergency care. Blood gas analyzers and portable lactate meters are common tools, but discrepancies between devices, especially at high lactate levels, have been reported. This study aimed to evaluate inter-device variability in canine lactate measurement. Lactate levels in 118 dogs were measured using a blood gas analyzer and a portable lactate meter. A strong correlation (R=0.906) was observed; however, the portable meter exhibited an 18% positive bias primarily characterized by additive error. These findings emphasize the need for careful device selection and the standardization of lactate measurement methods.

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A 10-year-old, male neutered pug dog with a history of gallstones was found to have a mass near the caudate lobe of the liver upon ultrasound examination. The mass was red to dark red, multinodular, measuring 3 × 3 × 4 cm and not continuous to the liver. Histopathological examination revealed sheet-like proliferation of polygonal neoplastic cells resembling hepatocytes with mild atypia, and no portal areas were observed. The tumor cells were positive for HepPar-1 and negative for cytokeratin 7. The macrophages decreased in neoplastic lesion compared to normal area. Based on these findings, this case was diagnosed as a hepatocellular carcinoma of ectopic liver origin. This is the second reported case showing the potential for ectopic liver to develop into tumors in dogs.

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A 5-year-old, 7.6-kg male miniature dachshund presented with right-sided congestive heart failure and ascites. Echocardiography revealed a tricuspid valve tumor. Open-heart surgery with cardiopulmonary bypass was performed via right atriotomy and the tumor was excised from the septal leaflet of the tricuspid valve. Histopathological findings confirmed the diagnosis of a myxoma. Postoperatively, the ascites resolved and no signs of right-sided congestive heart failure were observed. The dog remained clinically stable for 727 days after surgery. This conclusion reinforces the novelty of this report, as successful resection of a tricuspid valve myxoma has not been reported in the veterinary literature.

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We aimed to investigate the effects of desflurane (Des), sevoflurane (Sevo), and remifentanil (Remi) on the modulation of hemodynamic responses under 10-Hz electrical stimulation of the mental nerve in rabbits, which yields both hypertensive and hypotensive responses. Male Japan White rabbits (n=10, weight approximately 2.5 kg) were used. The systolic blood pressure (SBP) and diastolic blood pressure (DBP) of the animals before and after electrical stimulation of the mental nerve was observed at baseline and after administration of Sevo or Des and Remi. The magnitude of the blood pressure (BP) decrease and increase following electrical stimulation were observed. The BP hypotensive response was suppressed by Remi at 0.8 μg/kg/min; contrastingly, it was potentiated by Des and Sevo. The potentiating effect of Des or Sevo on the hypotensive response was counteracted by remifentanil. The suppression of the hypertensive response by Sevo 0.4 MAC was attenuated by the concomitant use of Remi 0.4 μg/kg/min. The hypertensive response was suppressed by Des, Sevo, and Remi. The combination of Des or Sevo with Remi suppressed hypertensive response. These results suggest that combined administration of Des or Sevo with Remi suppressed both hypotensive and hypertensive responses to electrical stimulation of the mental nerve in a well-balanced manner and stabilized the hemodynamics in rabbits.

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In veterinary surgery, the choice of suture is determined by the surgeon based on a combination of factors, such as differences in disassembly time, price, and suture site. However, no unified comparison has been made across companies, and the differences are often unclear. In this study, we compared the mechanical properties (maximum tensile load, maximum extension, and maximum twist) of seven synthetic absorbable sutures at baseline (day 0) and over time under different pH conditions (PBS: pH 7.2, acidic: pH 5.6, alkaline: pH 8.8). At baseline, the comparison showed no significant difference in tensile load, but monofilament sutures exhibited a significantly higher extension than multifilament sutures. In terms of twist, the results varied, with significantly higher values for PDS II and MonoSynthe, both of which are polydioxanone based, suggesting that material differences may have influenced the results. On the other hand, multifilament sutures showed lower values over time in all conditions compared to monofilament sutures. Therefore, it was concluded that multifilaments were more strongly affected by solution immersion than monofilaments and lost their mechanical properties earlier. The results also revealed distinct patterns in twist behavior over time, especially MonoSynthe exhibited much lower twist values under alkaline pH compared to other monofilament sutures. These results suggest that twist could be a valuable addition to conventional evaluation methods for suture characteristics. Further multifaceted evaluations will contribute to the development of more comprehensive selection criteria for sutures used in veterinary clinical practice.

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An 11-year-old castrated male Turkish Angora cat presented with chronic lethargy and inappetence was diagnosed with non-regenerative anemia, increased nucleated red blood cells, and thrombocytopenia. Tests for anemia-related infections were negative. Imaging revealed pleural effusion, hepatomegaly, splenomegaly, and enlarged abdominal lymph nodes, raising suspicion of a round cell tumor in the spleen. His anemia and pleural effusion did not improve despite chemotherapy with cytarabine administration. Erythroid precursor cells were identified in the pleural fluid. His condition deteriorated, progressing to dyspnea and necessitating euthanasia. Necropsy findings revealed extensive infiltration of CD71-positive neoplastic cells and a myeloid-to-erythroid precursor ratio of 0.02, indicating pleural metastasis. Pleural metastasis should be considered a differential diagnosis in feline acute erythroid leukemia cases presenting with pleural effusion.

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In horses, the gut microbiota plays a critical role in maintaining intestinal homeostasis and overall health, but antimicrobial administration can disrupt its balance, resulting in dysbiosis, which can cause antibiotic-associated diarrhea. This study assessed the impact of intravenous cephalothin sodium administration on the equine gut microbiota by using microbial amplicon sequencing targeting the 16S-ITS-23S rRNA operon. Fecal samples from 39 clinically normal horses, 16 antibiotic-treated horses (cephalothin, n=5; minocycline, n=5; metronidazole, n=6, each administered for 5 days), and seven colitis-affected horses were collected. Cephalothin had minimal effects on microbial diversity, as α-diversity and β-diversity did not differ significantly from those in clinically normal horses (P>0.05). In contrast, minocycline and metronidazole significantly disrupted the microbial composition. Colitis-affected horses exhibited severe microbial alterations, including reduced species richness. Among the 52 microbial families significantly altered in colitis horses, none showed significant changes in response to cephalothin, suggesting its gut-microbiota-friendly characteristics. Notably, Verrucomicrobia subdivision 3, associated with mucosal integrity, remained stable in the cephalothin group, whereas its relative abundance significantly decreased in the minocycline, metronidazole, and colitis groups (P<0.05). These findings suggest that cephalothin poses a lower risk of equine microbiota disruption than other antimicrobials, making it a safer option in veterinary practice. Cephalothin could help to maintain gut microbial balance while ensuring effective infection control and reducing gastrointestinal complications. This study provides valuable evidence for optimizing antimicrobial selection, supporting equine gut microbiota health.

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Felis catus papillomavirus (FcaPV) was first discovered in 2002. Seven genotypes (FcaPV-1/-2/-3/-4/-5/-6/-7) have been reported to date, at least one of which (FcaPV-2) is suggested to be implicated in squamous cell carcinoma (SCC); however, relevant epidemiological data on Japanese cats are limited. There is one report on relatively low FcaPV-2 prevalence in cats with SCC, largely in the Tokyo region. In this study, we investigated the prevalence of each FcaPV genotype in cats with SCC largely drawn from a peripheral region of Japan (Kyushu). Formalin-fixed paraffin-embedded (FFPE) specimens from 107 cats with SCC were subjected to DNA extraction for type-specific PCR assays, followed by confirmatory nucleotide sequencing. Overall, 16 cases (15.0%) were positive for FcaPV, and the results detected for FcaPV-1/-2/-3/-4/-5/-6/-7 were 0/107 (0.0%), 7/107 (6.5%), 4/107 (3.7%), 1/107 (0.9%), 3/107 (2.8%), 1/107 (0.9%), and 1/107 (0.9%), respectively. Our results suggest that FcaPV-2 is the prevalent papillomavirus type in cats with SCC across Japan, but the figure is lower than in other countries. This is also the first report on the detection of FcaPV-6 and FcaPV-7 in Japan, which previously have only been reported in Australia and New Zealand, respectively.

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Heat exposure at the physiological level of oocyte-cumulus-granulosa cell complexes (OCGCs) during in vitro growth (IVG) culture decreases the reduced glutathione (GSH) level of oocytes, an antioxidant, but its mechanism has been unclear. We subjected OCGCs to IVG for 4, 8, or 12 days and investigated the effects of heat exposure on the gene expression of cumulus-granulosa cells associated with antioxidant capacity. Heat exposure did not alter the expression of genes related to GSH synthesis or reuse. Conversely, heat exposure increased mRNA expression of superoxide dismutase 2 and decreased that of glutathione peroxidase 1, which are antioxidant enzymes. Ultimately, heat exposure alters the gene expression of antioxidant enzymes in growing follicles, which may indirectly decrease the GSH level of oocytes.

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Human pharmaceuticals are widely used in veterinary medicine. Nevertheless, identifying the optimal pharmaceuticals and dosages has been a significant challenge, as these medications may not be efficacious or may even be toxic to small animals. Following the approval of a pharmaceutical for human use, comprehensive non-clinical information is made public in Japan as Summary Technical Documentation (STED) and in the U.S. as Drug Approval Packages. As canines are often employed in non-clinical investigations, the information could prove invaluable in identifying the optimal pharmaceuticals and dosages. Sodium-glucose co-transporter 2 (SGLT2) inhibitors represent a class of anti-diabetic agents for humans, with a total of nine drugs currently approved in Japan, the U.S. and the E.U. Among them, dapagliflozin and empagliflozin have been approved for the treatment of chronic heart failure. In canines, myxomatous mitral valve disease (MMVD) represents the most prevalent etiology of chronic heart failure. Despite the recommendation of pimobendan and loop diuretics as standard-of-care medications, MMVD remains a disease with a poor prognosis due to its progressive nature. We examined the pharmacology, safety, and pharmacokinetics of the globally approved SGLT2 inhibitors (empagliflozin, canagliflozin, and dapagliflozin) in canines in the STED. Based on these results, we propose dapagliflozin as the most favorable pharmaceutical in canines. We also discuss the potential effects of SGLT2 inhibitors on canine MMVD, considering the similarities between canine MMVD and human chronic heart failure.

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A six years and four months old Japanese Black cow presented with a solid mass in the left and middle mandible. Treatment involved the administration of antibiotics and the mass was surgically removed. Recurrence of the mass was observed, and the cow exhibited hypersalivation and anorexia before dying naturally. A necropsy revealed a solid subcutaneous mass infiltrating the oral cavity and the left mandibular bone, with hemorrhage and necrosis. Histopathological examination revealed clear, plasmocytic, spindle-shaped, or polygonal neoplastic cells. The neoplastic cells were immunoreactive with cytokeratin, cytokeratin 5, vimentin, smooth muscle actin, and p63. Considering these findings, the mass was diagnosed as malignant myoepithelioma. This is the first report of malignant myoepithelioma arising from the salivary glands in a cow.

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Although gastrointestinal stromal tumors (GISTs) are rare in guinea pigs, few cases have been reported recently. Here, we present a case of a GIST in a guinea pig that showed atypical cellular morphology with extensive epithelioid-like cells. The tumor was located between the small intestine and the tip of the cecum and originated from the jejunum. Histopathologically, the tumor cells were mixed with epithelioid-like or short spindle-shaped cells with round-to-oval nuclei. Multinucleated cells were also observed. The tumor metastasized to the peritoneal lymph node. Immunohistochemically, the tumor cells were diffusely positive for vimentin and c-kit. A mutation (large deletion) in exon 11 of the KIT gene was detected using PCR-direct sequencing. Including the previous five cases, GISTs in guinea pigs tended to exhibit nuclear atypia rather than the typical morphology observed in canine GISTs, despite being diagnosed as spindle-shaped. Additionally, the present case exhibited more nuclear atypia, which may be a characteristic feature of GISTs in guinea pigs.

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This study sought to create a simple method for screening and detecting oral bacteria associated with periodontal disease as well as to identify the bacterial species that had the strongest correlation with disease severity in dogs. Fifty-two dogs from the Kagoshima University Veterinary Teaching Hospital were included. The periodontal disease status, which included gingival recession, root surface exposure, and gingival redness, was determined through visual examination. Oral swab samples were taken from each dog’s gingival margin or tooth cervix using a sterile cotton swab following a standardized protocol. The collected samples were applied to our nanotechnology named sugar chain immobilized magnetized gold nanoparticle/magnetic microparticle (SGNP/MMP) method to obtain bacterial DNA, which was then subjected to qualitative and semiquantitative PCR analyses for 6 genera and 8 species of bacteria: Porphyromonas gingivalis (P. gingivalis), Tannerella forsythia (T. forsythia), Treponema denticola (T. denticola), Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans), Fusobacterium nucleatum (F. nucleatum), Prevotella intermedia (P. intermedia), Porphyromonas gulae (P. gulae), and Porphyromonas cangingivalis (P. cangingivalis). The severity of periodontal disease was most strongly correlated with T. denticola (associated with the gingival recession), followed by slight total bacteria and P. gingivalis+P. gulae, but no significant correlation was found with P. gulae. Within the scope of this study, the analytical method used may represent a useful standard for screening and detecting specific bacteria, and the quantity of T. denticola is linked to the severity of periodontal disease in dogs.

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Bovine mycoplasma mastitis is highly transmittable and hard to treat by chemotherapy. It causes severe economic loss and is considered a major problem for milk production. Mycoplasma canadense is one of the causative agents of mycoplasma mastitis. A primer set to detect M. canadense was developed based on single nucleotide polymorphism-specific loop-mediated isothermal amplification. Using this primer set, 10 fg M. canadense DNA corresponding to the DNA amount of ~13 cells was detected within 40 min. Cross-reactivity with other bovine Mycoplasma spp., Acholeplasma laidlawii, and mastitis-related bacteria was not observed when ≤1 pg DNA was applied. These results would provide a basis for validating future experiments with spiked-milk and field samples for the development of rapid detection of M. canadense.

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House-soiling is the most common problem faced by cat owners and is the main reason for owners surrendering cats to animal shelters. Although many studies have reported on inappropriate cat excretion in relation to the toilet environment, few reports have explored the preferences of cats kept indoors when multiple litter boxes are presented. In this study, we investigated the effect of litter box size and litter types on the excretion behavior of cats and whether a litter environment that combines their preferred elements would change their excretion behavior. Our findings indicated that cats preferred litter boxes measuring ≥50 cm as well as clumping clay litter. Moreover, a comfortable litter environment combining these two elements promoted normal urination behavior while improving house-soiling (both urination and defecation) as well as three dissatisfied behaviors during excretion. The results of the present may be beneficial for cat owners and cats exhibiting house-soiling, and they could facilitate the reduction of the number of cats being abandoned owing to house-soiling.

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Endotracheal intubation plays a crucial role in airway management in mice. Transoral endotracheal intubation (TEI) offers a less invasive alternative to tracheostomy and is more ideal for chronic experiments. Despite the development of various TEI techniques in mice, the lack of accessible and well-established methods that do not require specialized equipment hinders routine research. We developed a feasible and highly successful method for TEI in C57BL/6JJcl mice using a combination of commercially available research equipment. A success rate of 97.5% was achieved within 21.2 ± 8.9 sec (mean [standard deviation]) with no observed complications in the 40 mice studied. This method simplifies TEI without specialized tools and provides practical guidance for consistent application in routine research settings.

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This study investigated the seroprevalence of bovine leukemia virus (BLV) in beef breeding cattle in Ibaraki, revealing a seroprevalence of 43.0% with a bimodal distribution in farms classified as either BLV-negative or very-highly infected. These results underscore the need to implement appropriate strategies for very-highly infected farms. In particular, determining the culling prioritization of cattle is absolutely necessary. It was revealed that effective control in very-highly infected farms is difficult based on types of operation or herd size. On the other hand, high-transmission-risk cattle were widely distributed across entire Ibaraki and were significantly more prevalent in very-highly infected farms. These findings suggest that the transmission risk classification is a potentially effective strategy for culling prioritization under the current circumstances in Ibaraki.

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Postpartum depression is a prevalent mental disorder that affects mothers and has adverse effects on families. The decline in parenting quality associated with postpartum depression raises concerns about the adverse impact on children. Therefore, it is desirable to prevent deterioration in parenting quality in depressed mothers. This study aims to investigate whether antidepressive agents can prevent the decline in parenting quality associated with postpartum depression. Maternal care and sucrose palatability were evaluated in postpartum female mice with intraperitoneal lipopolysaccharide (LPS) administration 24 hr before testing. In the maternal care test, LPS increased the latency to retrieving pups into the nest and to crouching over the pups in the nest and decreased the duration for crouching over the pups. Furthermore, in the sucrose preference test, the ratio of sucrose intake decreased. Next, dopamine D2 receptor agonists (quinpirole and bromocriptine), a selective serotonin reuptake inhibitor (fluoxetine), or a tricyclic antidepressant (imipramine) was intraperitoneally administered 30 min before LPS administration. Treatment with quinpirole and bromocriptine, but not fluoxetine and imipramine, decreased the crouching latency and increased the crouching duration in LPS-treated postpartum females. On the other hand, all of the antidepressive agents did not affect the ratio of sucrose intake. Furthermore, the dopamine D2 receptor antagonist haloperidol disturbed the effects of quinpirole and bromocriptine on maternal care. These results indicate that dopamine D2 receptor agonists can prevent the decline in parenting quality via dopamine D2 receptor in LPS-induced postpartum depression model mice.

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Lingual canine T-zone lymphoma (TZL) is a rare form of extranodal canine lymphoma. 7-years and 5 months old, spayed female toy poodle presented with a red swollen mass on the tongue. A punch biopsy of the lesion was conducted, followed by histopathological and immunohistochemical analyses. Despite the absence of a lymph node excisional biopsy, the case was diagnosed as canine lingual TZL. Although there is no established treatment for lingual TZL, treatment often follows TZL protocols. In this case, the tongue lesion improved after the administration of oclacitinib, a drug approved for canine atopic dermatitis. We present this case due to its successful management with oclacitinib, without the use of conventional anticancer therapy.

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There are various treatments have been reported for canine babesiosis. However, treatment methods that can eliminate the parasites have not been established. The current study aimed to evaluate the therapeutic effects of tafenoquine against natural Babesia gibsoni infection. In total, seven dogs with canine babesiosis and one dog with canine babesiosis not controlled with diminazene aceturate were included. Oral tafenoquine at dose of 10–20 mg/kg was administered orally on days 0 and 7. The hematocrit level and platelet count of the dogs were measured. The clinical symptoms of all dogs rapidly improved. Two dogs relapsed. However, their symptoms improved after two more doses of tafenoquine. Although recurrence could not be prevented, tafenoquine might be a treatment against canine babesiosis.

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Marek’s disease virus (MDV) is an oncogenic herpesvirus that causes malignant lymphomas in chickens (Marek’s disease, MD). Although MD is currently well controlled by vaccination, field strains of MDV tend to increase in virulence, and sporadic outbreaks have been reported worldwide, including in Japan. Previously, we determined the whole-genome sequence of a Japanese MDV strain, Kgs-c1, isolated in 2014, and analyzed its genetic characteristics. However, to date, Kgs-c1 is the only MDV strain that has been subjected to whole-genome sequencing, leaving the possibility that the key genetic features of the Japanese strains remain undiscovered. Therefore, we conducted whole-genome sequencing of two MDV strains, Kgs-c2 and Sg-c1, isolated in 2016 and 2019, respectively, and analyzed their genetic characteristics. Consistent with our previous findings, the genomic sequences of the Japanese strains were classified into the Eurasian cluster, suggesting that the Japanese strains are genetically closer to the European and Chinese strains than they are to the US strains. In contrast, the Japanese strains exhibited genetic features different from those of pathogenic European and Chinese strains. Furthermore, polymorphisms in the meq and infected cell protein 4 (ICP4) genes, which are candidates involved in the enhanced virulence of MDV, were observed among the newly isolated strains and Kgs-c1. Thus, three MDV strains isolated in Japan had different genetic features from those in other countries. These findings emphasize the necessity of periodic monitoring of MDV field strains in order to determine shifts in their characteristics and effectively control MD.

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Enzootic bovine leukosis (EBL) can significantly impact herd productivity. This study aimed to elucidate the factors contributing to the inability of cattle with EBL to stand. A total of 82 cattle with EBL were analyzed, with 40.2% exhibiting an inability to stand. The duration of veterinary therapy was found to be related to severe trauma, leading to the inability to stand. Although an increase in the number of organs affected by tumors showed a trend toward an inability to stand, only spinal canal tumors were identified as directly causing this issue by filling the spinal canal and infiltrating the nerve. Therefore, it is essential to assess EBL in cattle unable to stand without an apparent reason to avoid unnecessary treatments.

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Fecal samples were obtained from cats rescued in various areas of Japan and examined to determine the presence of parvovirus (PV) genes. Feline panleukopenia virus (FPV), feline bocavirus (FBoV) types 1, 2, and 3, and feline chaphamaparvovirus were detected, whereas canine parvovirus and feline bufavirus were not. Regarding FPV, FBoV-1, and FBoV-2, the number of positive cases was significantly greater in cats with diarrhea symptoms than in those without. Among the positive cases, cats aged 1 to 2 months exhibited a significantly higher rate of diarrhea symptoms than those over 3 months old. These findings indicate that infection with novel PVs is associated with the development of diarrhea symptoms in kittens that are 1 to 2 months old.

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Glaesserella parasuis, the causative agent responsible for Glässer's disease in swine, leads to severe polyserositis, meningitis, and arthritis, posing a significant threat to swine production. The LuxS/AI-2 quorum sensing system is crucial for G. parasuis growth, biofilm formation, and pathogenicity. Quorum sensing inhibitors, such as paeoniflorin (PF), offer a potential strategy to mitigate antibiotic resistance. This study evaluated PF’s effects, alone and combined with antibiotics, on quorum sensing, biofilm formation, and virulence gene expression of drug-resistant G. parasuis. PF significantly reduced AI-2 production, biofilm formation, and virulence genes expression in vitro. A viable model for G. parasuis infection was established using KM mice, and demonstrated that a low-dose combination of PF and lincomycin effectively mitigated organ damage, reduced bacterial load in the liver, and improved survival rates compared to individual treatments in vivo. These findings suggest PF as a promising quorum sensing and virulence inhibitor for controlling G. parasuis infections. Further research is warranted to optimize its clinical application.

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Meningothelial proliferative diseases can rarely occur in extracranial sites, but there is limited information about them in veterinary medicine. This study investigated cutaneous meningothelial proliferative disease in eleven cats. Five cases were microscopically diagnosed with cutaneous meningioma and six cases with meningothelial hamartoma. Three of the former cases were subclassified as fibrous type and two as meningothelial type. The proliferating cells were positive for vimentin and E-cadherin, partially positive for cytokeratin, and negative for S100. All the lesions were located in the midline of the parietal skin and occurred at a young age. These facts suggest that both diseases in cats may be a congenital disease caused by ectopic meningothelial remnants during the fetal period.

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Bovine leukemia virus (BLV), a retrovirus that is widespread worldwide, causes enzootic bovine leukosis (EBL), a B-cell leukemia/lymphoma with a poor prognosis that ultimately results in death. In Japan, the number of cattle infected with this virus is increasing, and it is estimated more than 35% of cattle are currently infected. Since no vaccines or treatments against BLV infection are currently available, it is important to establish a method of early diagnosis for EBL to reduce economic losses caused by the disposal of EBL cattle in Japan, where a large number of expensive beef cattle are raised. We previously developed Rapid Amplification of the Integration Site without Interference by Genomic DNA Contamination (RAISING), a cost-effective, rapid, and sensitive method for the clonality analysis of BLV-infected cells. Despite its usefulness for the early diagnosis of EBL, RAISING had drawbacks preventing its practical application. Here, we report the development of an improved method, RAISING ver.2, and its performance. Compared to BLV clonality analysis using the previous method, RAISING ver.2 was found to maintain high accuracy and reproducibility despite its simplification. Moreover, its performance was also validated in a multicenter validation study. Taken together, our results strongly suggest that RAISING ver.2 can be fully utilized in clinical practice. Successful commercialization of a RAISING test kit could overcome the concerns of livestock farmers suffering from EBL, thereby promoting a stable supply of Japanese beef, both domestically and internationally.

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This is the first report of paroxysmal atrioventricular block with Wenckebach cycles in a dog exhibiting syncope. The patient was a 1-year-old female Shiba Inu referred to our hospital with chief complaints of exercise intolerance, dizziness during walking, and tongue discoloration. Pacemaker implantation was performed based on the clinical presentation and Holter electrocardiogram findings. In this case, long-term management was successfully achieved for 13 years and 3 months (Age 15 years old) after the placement of pacemaker. A histopathological examination revealed that no abnormalities in the conduction system were detected that could explain the arrhythmia. Consequently, the arrhythmia was suspected to have been caused by vagus nerve stimulation.

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Streptococcus uberis, a Gram-positive bacterium commonly found in dairy cows, causes mastitis and decreases milk production quality. While usually non-pathogenic in humans, rare cases of infections such as endocarditis and abscesses have been reported. This paper presents the first documented case of Streptococcus uberis infection in a whooper swan, leading to systemic illness. The swan exhibited hepatic necrosis, spleen congestion, and heart abnormalities, with bacterial presence confirmed through microbiological methods. The source of infection remains to be elucidated but is possibly linked to exposure to wild animals or environmental factors in the zoo habitat.

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Porcine circovirus type 2 (PCV2) induces wasting and immunosuppression in pigs and is widely transmitted in pig farms worldwide. Classical swine fever (CSF) is a particularly important contagious disease in pigs. In CSF-endemic areas, such as Japan, thorough vaccination is performed, and effective use of the CSF vaccine is important to prevent outbreaks. This study investigated the impact of PCV2 infection on the immune response to CSF vaccines in field farms. The mortality rate of fattening pigs on the farm was investigated, and pig sera were used to measure the PCV2 viral load and neutralizing antibody titer of CSF as indicators of CSF vaccine efficacy. Results indicated a sharp increase in mortality rate, PCV2 detection rate reaching 100%, and high viral load, whereas CSF antibody titers were significantly lower in the fattening pig herd. After PCV2 inactivated vaccination was initiated, the mortality rate, PCV2 detection rate, and viral load in fattening pigs decreased, and CSF antibody titers also improved. Furthermore, there was a correlation between higher PCV2 viral load and lower CSF antibody titers in this farm. In contrast, other PCV2-vaccinated farms had higher CSF antibody levels. These results indicate that PCV2 infection negatively affects the efficacy of CSF vaccines, and the control of PCV2 in field farms is important.

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Human epidermal growth factor receptor 2 (HER2) is a known therapeutic target in canine osteosarcoma (OSA); however, the efficacy of anti-HER2 antibody drugs remains unclear. This study aimed to investigate the effects of the anti-HER2 antibody drugs including trastuzumab and trastuzumab emtansine (T-DM1) on canine OSA cell lines in vitro and in vivo. Four canine OSA cell lines (HMPOS, POS, OOS, and HOS) were used. Western blotting revealed HER2 protein expression in all the cell lines. Although water-soluble tetrazolium salt assays showed growth inhibitory activity of trastuzumab and T-DM1 against all the cell lines in vitro, the activity of T-DM1 was significantly stronger than that of trastuzumab. Flow cytometric analysis of the canine OSA cell line (HMPOS) revealed that T-DM1, but not trastuzumab, significantly increased the sub-G1 phase fraction in cell cycle analyses and the percentage of early and late apoptotic cells in annexin V apoptotic assays. For in vivo experiments, canine OSA cells (HMPOS) were subcutaneously injected into nude mice. Six days after inoculation, trastuzumab, T-DM1, or the vehicle control was administered intraperitoneally once per week. Survival until the tumor volume in the canine OSA-engrafted mice reached mean final tumor volume in the T-DM1 group was significantly longer in the T-DM1 group, but not in the trastuzumab group, compared to the vehicle control group. These findings indicated that T-DM1 exerts antitumor effects on canine OSA cells in vitro and in vivo, possibly by inducing apoptosis due to DM1.

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There is a clinical challenge in decision-making regarding prophylactic glaucoma treatment based solely on intraocular pressure (IOP) trends for long-term cataract management or before phacoemulsification surgery in canines. This study aimed to compare IOP and ultrasound biomicroscopy (UBM) parameters with cataract maturity in small dog breeds. We conducted a retrospective review of medical records pertaining to ophthalmic examinations and UBM assessments of small breed dogs diagnosed with cataracts at the Veterinary Medical Teaching Hospital of Seoul National University from January 2020 to August 2024. UBM images obtained under topical anesthesia were analyzed to quantify various parameters. Subsequently, the 47 eyes examined were classified into four groups according to cataract maturity. The ciliary cleft area (CCA), ciliary cleft length (CCL) and width (CCW), and iridocorneal angle (ICA) were measured. The measured values were compared to determine their degree of correlation with cataract maturity. Statistical analyses of patient demographics were also performed. Both CCA (P=0.0024) and CCL (P=0.0004) decreased significantly with increasing cataract maturity. However, IOP, CCW, and ICA were not significantly associated with cataract maturity. Age and sex did not have significant effects on any dependent variable. Among the UBM parameters, CCA and CCL demonstrated a significant correlation with cataract maturity, indicating structural alterations in the ICA might develop in association with cataracts, independent of direct IOP effects. These findings underscore the importance of considering prophylactic glaucoma management in patients with advanced cataracts to mitigate potential complications.

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Live vaccination is the most protective method against bovine neosporosis, which is the major cause of bovine abortion globally. Here, the Neospora caninum parenteral strain Nc1 and NcGRA7-deficient N. caninum (NcGRA7KO), which is less virulent in mice, were evaluated as potential live vaccines. BALB/c mice were subcutaneously inoculated with high (1 × 10⁵) or low (1 × 10⁴) doses of tachyzoites. At high doses, Nc1-inoculated female mice presented decreased body weight gain and increased clinical signs and died before challenge infection with green fluorescent protein (GFP)-expressing Nc1 (Nc1-GFP), whereas NcGRA7KO-inoculated animals exhibited increased survival before and after challenge infection. Although inoculation of female mice with Nc1 or NcGRA7KO resulted in a lower brain parasite number of challenged Nc1-GFP than in noninoculated animals, the total brain parasite burden in NcGRA7KO-infected mice decreased compared with that in Nc1-infetced animals. At low dose of NcGRA7KO, increased survival rates of mice and lower total brain parasite number were observed compared with high dose of NcGRA7KO. In male mice, a significant lower brain parasite burden of Nc1-GFP was observed in both high and low doses of NcGRA7-inoculated mice, and the total parasite number in the brains of low dose of NcGRA7KO-inoculated animals was lower than that in the brains of high dose of NcGRA7KO-inoculated or noninoculated animals. In conclusion, these results suggest that NcGRA7KO parasites have potential for use as a live vaccine against N. caninum infection.

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Although velogenic Newcastle disease viruses (NDVs) generally show low pathogenicity in waterfowl such as ducks, lethal infection by NDVs has been reported sporadically. A previous study revealed that a serially-passaged NDV isolate showed increased virulence in ducks, and that the viral proteins harbored a total of 11 amino acid substitutions. Among them, the fusion protein (F), matrix protein (M), and hemagglutinin-neuraminidase (HN) were suspected to be involved in enhanced virulence. The present study aimed to clarify the association between genetic mutations in NDVs and pathogenicity in ducks by comparing histopathological findings in ducks inoculated with three recombinant (r)NDVs: rM44 (Q44R substitution in M), rF142 (I142M substitution in F), and rM+F+HN (Q44R, N123D, and D342N substitutions in M; I142M and E304K substitutions in F; and G538R substitution in HN; three viral proteins compatible with amino acid sequences from passaged NDV). Seven-day-old ducks were intranasally inoculated with rM44, rF142, or rM+F+HN. Gross and histopathological lesions in the heart, thymus, brain, and pancreas were more severe in ducks inoculated with rM+F+HN than in ducks inoculated with rM44 or rF142. In particular, myocarditis associated with NDV antigens and mixed inflammatory cells was prominent in rM+F+HN-inoculated ducks. Therefore, the increased virulence of NDV in ducks is not due to a single amino acid substitution in one protein, but rather to the synergistic effects of multiple mutations in three viral proteins.

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Human schistosomiasis is a serious parasitic disease caused by infection with Schistosoma japonicum. In order to establish monitoring sites in the S. japonicum endemic area in the Obitsu River basin in Chiba Prefecture, Japan, we investigated the habitat of the intermediate snail host, Oncomelania hupensis nosophora using geographic information systems (GIS). A series of thematic maps of soil types, land-use, and past wetlands were compared to the distributions of patients and O. h. nosophora habitats to identify environmental conditions associated with high risk of the disease. In addition, we divided the period from the 1600s to the present into four sub-periods to estimate how the habitat of O. h. nosophora has changed. Our study identified the present risk areas in the Obitsu River basin that should be monitored consecutively, taking into account future global environmental changes that may have the potential to promote re-emergence of the disease.

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This study examined the relationship between teat canal score (TCS), somatic cell count (SCC), pathogen infection, and milk antimicrobial components in each quarter of milking cows. A total of 110 quarters of 28 healthy Holstein milking cows were used for the TCS and collection of milk samples. Milk samples were analyzed for SCC, antimicrobial components (S100A7 and lingual antimicrobial peptide (LAP)), and acute phase protein (serum amyloid A (SAA)). Milk samples with SCC of at least 10⁵ cells/mL were cultured to isolate and identify the causative organism. A total of 110 teats were classified, TCS of 1, 2, 3, 4 in 60.9% (67), 26.4% (29),11.8% (13) and 0.9% (1) teats, respectively. A positive correlation (r=0.6915, P<0.0001) was found between the TCS and SCC in all teats. Pathogens were detected in 100% of milk samples from TCS ≥3 milk and 91% of those from TCS 2. However, pathogens were detected in only 33% of milk samples from TCS 1, a significantly (P<0.0001) lower detection rate than those from TCS 2 and ≥3. The LAP concentration in the group with detected pathogen was significantly (P<0.01) higher than that in the no growth group. The results suggest that in quarters with higher TCS, SCC and LAP concentrations were significantly higher, milking it easier to detect pathogens due to the greater likelihood of bacterial invasion.

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A 5-year-4-month-old neutered female French bulldog had a brain mass that was surgically excised. Histologically, the tumor consisted of neoplastic oligodendroglial and spindle-shaped cells, and chondroid tissues. Immunohistochemically, oligodendroglial cells were immunopositive for oligodendrocyte transcription factor 2 (OLIG2), 2', 3'-cyclic nucleotide 3'-phosphodiesterase (CNPase), platelet-derived growth factor receptor alpha (PDGFRA), vimentin, cluster of differentiation 44 (CD44), and WW domain containing transcription regulator 1 (WWTR1). Spindle-shaped cells were immunopositive for OLIG2, vimentin, CD44, and WWTR1. In chondroid tissues, chondrocyte-like cells were immunopositive for OLIG2, PDGFRA, vimentin, and WWTR1. In the present case, the tumor had oligodendroglial features accompanied by mesenchymal and chondroid metaplasia. Based on these findings, the dog was diagnosed with an oligosarcoma with chondroid metaplasia.

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A 5-year-old castrated male domestic shorthair cat was diagnosed with diabetic ketoacidosis and severe insulin resistance. Although the conventional treatment for diabetic ketoacidosis was provided, the cat required frequent hospitalization because of severe dehydration and repeated diabetic ketoacidosis. We detected anti-insulin antibodies for human in this cat. Serum insulin-binding IgG levels were markedly elevated compared with those in healthy cats and other diabetic cats. We initiated prednisolone to suppress the effects of anti-insulin antibodies. After initiation of prednisolone, the cat was gradually recovered with increasing activity and appetite. Furthermore, satisfactory glycemic control was achieved with combined subcutaneous injection of insulin detemir and insulin degludec.

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Atlanto-axial (AA) instability due to ligament insufficiency is a common cause of cervical spinal cord compression in toy breeds. However, in some dogs a difference in size between the atlas and the axis leads to joint incongruence that exacerbates AA subluxation and makes surgical treatment challenging. Twelve dogs with AA instability with incongruence were enrolled in a single institution prospective observational study. Computed tomography (CT) and magnetic resonance imaging (MRI) of the AA joint were compared to a retrospectively reviewed control group. A novel surgical approach consisting of a dorsal internal fixation technique was performed in six dogs. For affected dogs, the mean normalised difference between the dorso-ventral atlas canal and the dorso-ventral axis canal was 29.67% (median of 35.07%, standard deviation 25.64%), while in normal dogs a mean difference of 4.67% (median of 3.95%, standard deviation 5.21%) was observed. On MRI, 12/12 affected dogs had spinal cord compression, which was classified as reducible (3/12), partially reducible (6/12) and non-reducible (3/12). In surgically operated dogs, follow-up CT showed a partial or complete reduction of the previous spinal cord compression with a consistent amelioration or resolution of the presenting complaints. The proposed surgical technique was safe and effective in dogs with partially or completely reducible spinal cord compression.

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This article released online on July 30, 2014 as advance publication has been retracted by the Editorial Board of Journal of Veterinary Medical Science due to a violation of the journal’s “Information for Authors”.

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This article has been retracted by the Editorial Board of Journal of Veterinary Medical Science due to a violation of the journal's “Information for Authors”.

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This article released online on August 9, 2013 as advance publication was withdrawn from consideration for publication in The Journal of Veterinary Medical Science at author's request.

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This article released online on August 9, 2013 as advance publication was withdrawn from consideration for publication in The Journal of Veterinary Medical Science at author's request.

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This article released online on September 26, 2012 as advance publication was withdrawn from consideration for publication in The Journal of Veterinary Medical Science at author's request.

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This article released online on August 3, 2012 as advance publication was withdrawn from consideration for publication in The Journal of Veterinary Medical Science at author’s request.

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