Various aspects of movement, excavation, ecology, and muscle structure of Gymnophiona species have been reported. However, the unique mechanisms and dynamics of peristaltic locomotion and excavation are unclear, particularly for soil-inhabiting Gymnophiona spp. Previous studies primarily focused on forward locomotion and thrusting behavior, with less attention paid to the underlying vertebral and muscular mechanisms. Herein, using X-ray computed tomography, video analysis, and tissue specimens, we determined that the Mexican caecilian (Dermophis mexicanus) could generate peristaltic locomotion via coordinated bending and extension of the vertebral column and associated musculature, including the M. dorsalis trunci, M. subvertebralis, and external muscular sheath, facilitating both forward and backward movement. Thrust forces akin to a multistep spring mechanism are generated by extending their twisted and bent spines across the head, neck, chest, and abdomen. Each region flexes its vertebrae and modulates muscle size to fulfill various functions. The spinous processes of the vertebrae are loosely connected to independent segmental annuli via tendons. Unlike snakes, caecilians can move forward and backward by bending and stretching their spinal columns within their bodies, allowing movement through soil when there is space for their heads and bodies, which confers remarkable survival advantages. Dorsoventral and right–left dynamics of the spinal and muscular structures and the locomotion of Mexican caecilians was confirmed.

Nasopharyngeal stenosis (NPS) is a common upper airway disorder in cats, and balloon dilation (BD) is considered the least invasive treatment. However, advancing a BD catheter can be challenging in cases of severe or imperforate NPS. This technical note describes a simple access-establishing technique that enables BD in such cases. Six cats with NPS in which BD catheter passage was difficult underwent a modified procedure in which a 6-Fr tube was advanced transnasally and connected to an 8-Fr tube, enabling successful BD catheter placement in the nasopharynx. Dilation was confirmed via endoscopy, and all cases showed clinical improvement. No complications were directly attributable to the access technique. This method may facilitate BD in severe feline NPS.

Plasma D-dimer concentrations were measured in 15 cases with thromboembolism and 19 cases without thromboembolism among bovine patients with inflammatory diseases, and the clinical usefulness of plasma D-dimer as a thromboembolic marker was evaluated. No significant difference in plasma D-dimer concentrations was observed between the two groups. A receiver operating characteristic curve was created, and with a plasma D-dimer cutoff value of 0.38 mg/L, the sensitivity and the specificity were 86.7% and 31.2%, respectively. Furthermore, there was a large variability in plasma D-dimer concentrations in cases with thromboembolism. These results indicate that the measurement of plasma D-dimer alone in the diagnosis of thromboembolism in cattle does not have sufficient specificity. In a multivariate logistic regression analysis regarding thromboembolism detection, platelet count was significant in the likelihood ratio test, suggesting that considering platelet count in addition to plasma D-dimer may allow for the detection of thromboembolism.

The clinical, histological, and immunohistochemical features of 26 fibrous proliferative lesions in the vagina of 14 female dogs (13 intact and 2 neutered) were examined. These lesions presented as nodular or pedunculated masses. Histopathological examination revealed that all lesions consisted of spindle- and stellate-shaped cells with mild atypia, collagenous stroma, and blood vessels. Mitotic figures were rare. The number of blood vessels was significantly greater in pedunculated masses than in nodular masses. Immunohistochemically, spindle- and stellate-shaped cells were positive for progesterone receptor in all 26 lesions, estrogen receptor in 5 of 26 lesions, desmin in 20 of 26 lesions, and α-smooth muscle actin (αSMA) in 8 of 26 lesions. Lesions in neutered dogs exhibited lower progesterone receptor expression and higher estrogen receptor expression than those in intact females. No significant differences in desmin or αSMA expression were observed between the two groups. These findings suggest that the fibrous proliferative lesions in the canine vagina described in this study may represent progesterone-associated benign proliferative changes composed of myofibroblasts.

The interaction between gut bacteria and their host is vital for the early diagnosis and treatment of disease in captive animals. Here, we report a 16S rRNA sequencing-based bacterial profile during the progression of cardiovascular disease and drug treatment in a captive giant panda (Ailuropoda melanoleuca). We observed changes in the composition of bacteria associated with inflammation and regulating nutrient metabolism. Predicted metabolic functions also exhibited alterations. The remarkably reduced gut microbiome diversity, along with the imbalance in community interaction networks, indicated possible gut dysfunction. Our findings represent the first description of gut bacterial changes in a giant panda with cardiovascular disease. Maintaining symbiotic bacteria diversity is crucial for preventing health issues in captive animals and advancing wildlife conservation efforts.

Serological monitoring of infectious diseases in laboratory rodents is vital for ensuring animal health. Therefore, we have previously developed a multiplex immunochromatographic assay (ICA) to detect antibodies against six pathogens as follows: mouse hepatitis virus, Sendai virus, and Clostridium piliforme (Tyzzer's disease) in mice, and Seoul type orthohantavirus, Sendai virus, and sialodacryoadenitis virus in rats. However, the preparation of these strips is time-consuming and labor-intensive. Therefore, this study aimed to determine the long-term storage conditions for the developed multiplex ICA strips. The multiplex ICA strips stored in the polyethylene zipper-sealed bags (poly_bags) at –30 °C maintained detectable reactivity for all six targeted pathogens for 36 months, regardless of the presence or absence of desiccants, oxygen absorbers, or a vacuum state. However, when stored at 18–28 °C (room temperature) and 4 °C, the detectable reactivity of the multiplex ICA strips stored in poly_bags was reduced for some of the six targets pathogens at 18 months after storage. This reduction was not prevented by the storage with the desiccants and in the vacuum-sealed poly_bags (vacuum_bags). The oxygen absorber reduced detectability of the multiplex ICA strips. These results indicate that storing ICA strips in poly_bags at –30 °C, which is a simple method, is able to maintain detectability long-term for the strips format and pathogen targets examined in this study.

A captive male Japanese raccoon dog died after self-mutilation by biting its tail and developing anorexia. At necropsy, ulceration of the tail root and pelvic region, an abdominal mass, multifocal nodules in the lungs, and thrombi in the heart were observed. Histopathological examinations revealed multifocal pyogranulomatous inflammation in the lungs, abdominal mass, spleen, brain, liver, and kidneys. Gram-positive bacterial aggregates were observed in the lungs, abdominal mass, and spleen. These organisms were partially acid-fast and periodic acid-Schiff-positive, and branching filaments were observed on Grocott’s methenamine silver staining. Nocardia aobensis was identified in the abdominal mass by PCR and sequence analysis. These findings suggest that N. aobensis should be considered a potential cause of disseminated pyogranulomatous disease in animals.

Inflammation suppresses erythropoiesis, leading to non-regenerative anemia in dogs. Currently, clinical evidence of this inhibitory effect remains limited. This study provides important clinical insight by demonstrating a negative correlation between C-reactive protein (CRP) concentration and reticulocyte count over time in dogs with inflammatory anemia. This study aimed to leverage inflammatory anemia as a model to examine the longitudinal relationship between CRP levels and reticulocyte counts in dogs. Medical records of 23 dogs diagnosed with various inflammatory conditions and persistently non-regenerative erythropoiesis were retrospectively reviewed. Serial results of hematological and serological parameters were analyzed using linear mixed-effects models to account for intra- and inter-individual variation. Reticulocyte counts in anemic dogs with resolving underlying inflammatory conditions were significantly negatively correlated with CRP levels (standardized β = −0.53, 95% confidence interval (CI) −0.68 to −0.37; P<0.001). Moreover, cross-sectional analysis revealed that higher CRP levels were significantly associated with lower reticulocyte counts, suggesting that the severity of inflammation may be linked to reduced reticulocyte counts (Pearson’s r = −0.5; P=0.01). Similarly, erythropoietic responses to darbepoetin alfa appeared to be attenuated in dogs with elevated CRP concentrations. In these dogs, whose mean CRP concentration was 6.15 mg/dL, the onset of reticulocytosis was delayed approximately twofold, and the increase in peak reticulocyte count was approximately 38% lower than that in dogs with normal CRP concentrations. This study provides clinical evidence supporting an association between systemic inflammation and reduced or delayed reticulocytosis in dogs, highlighting the clinical utility of concurrently monitoring CRP and reticulocyte levels to assess disease progression and inflammatory recovery.

The incidence of enzootic bovine leukosis, which is due to bovine leukemia virus (BLV), has been increasing in Japan. However, large-scale surveys have not been conducted in recent years, and the impact of cattle harboring high BLV proviral loads on within-farm BLV prevalence remains unclear. To clarify the situation, questionnaires and PCR and serological testing for BLV were conducted between 2022 and 2024 on 95 beef breeding farms (3,082 cattle) and 9 Japanese Black fattening farms (140 cattle) in the Tohoku region. We also examined the effects of various factors on within-farm proportions of BLV-positive cattle. The proportions of PCR-positive and seropositive cattle were 34.3% and 35.9% in beef breeding cattle and 15.7% and 15.0% in Japanese Black fattening cattle, respectively. Among the 74 farms with at least one PCR-positive animal, the proportion of PCR-positive cattle was significantly higher on farms with at least one animal with a high proviral load (≥400 copies/10 ng DNA) than on farms without any such cattle. Similarly, farms where high-proviral-load cattle accounted for ≥10% of the herd had significantly higher proportions of PCR-positive cattle. In addition, farms that used public pastures, practiced on-farm grazing, or had experienced enzootic bovine leukosis within the past 5 years had significantly higher proportions of PCR-positive cattle. These findings suggest that BLV prevalence in beef cattle in the Tohoku region remains comparable to that reported approximately 10 years ago, indicating that BLV transmission in this region may be under control. Furthermore, cattle with high proviral loads may adversely affect within-farm BLV prevalence, indicating that targeted control measures focusing on such animals are essential for effective BLV control.

Mastitis is one of the most common diseases in dairy cows, causing significant economic losses due to reduced productivity and the need for treatment. In recent years, MRSA (methicillin-resistant Staphylococcus aureus) has emerged as an important cause of chronic and recurrent mastitis, posing additional challenges for herd health management. The aim of this study was to conduct a comparative analysis of recurrent mastitis in Holstein-Friesian cows caused by MRSA and non-MRSA Staphylococcus aureus, with a particular focus on the number of recurrences, somatic cell count (SCC), milk production, and risk factors. The study included 120 cows, divided into two groups of 60, raised under identical conditions on a single farm. Milk samples were collected under sterile conditions, cultured on Blood agar and Mannitol Salt agar, and analyzed for the presence of MRSA using PCR for the mecA gene. Cows were monitored for the number of recurrences, SCC, daily milk yield, and response to therapy. Statistical analyses included t-tests, ANOVA, correlation analysis, and logistic regression. The results showed that MRSA-infected cows had significantly higher recurrence rates, along with elevated SCC and reduced milk yield compared to the non-MRSA group. MRSA was identified as the strongest independent risk factor for mastitis recurrence. These findings highlight the importance of regular bacteriological monitoring, appropriate therapy, and preventive measures to reduce economic losses and protect herd health.

Long-term monitoring of viruses and Varroa destructor within the same honey bee colonies is rare in Japan. Thus, we conducted a 4-year fixed-point survey of three Apis mellifera colonies in Tokyo with monthly screening for seven viruses (using polymerase chain reaction) and Varroa infestation. Deformed wing virus was detected year-round, whereas sacbrood virus and black queen cell virus peaked in spring and summer. Israeli acute paralysis virus appeared sporadically, without seasonal trends. Varroa infestation rates (monitored during the latter 2.5 years) did not correlate with the number of detected virus types and showed no seasonality. Although viral load was not quantified, this long-term dataset provides valuable baseline data on local virus dynamics, providing baseline information on seasonal virus dynamics in managed honey bee colonies in Tokyo.

Fesaviruses, members of the group of picorna-like viruses, were discovered in 2014 in stool samples from cats in an animal shelter in the United States. In this study, we investigated the serological evidence of fesavirus 4 infection in domestic cats in Japan using a purified recombinant antigen corresponding to a portion of the large open reading frame of fesavirus 4. An enzyme-linked immunosorbent assay was developed and used to test 100 cat plasma samples to detect specific antibodies against the fesavirus 4 antigen and Western blotting confirmed presence of specific antibodies against the fesavirus 4 antigen in 12 samples. These findings highlight the importance of investigating newly discovered viruses circulating in companion animals in Japanese animal shelters.

This retrospective study investigated the bacterial species distribution and antimicrobial susceptibility of canine ocular isolates submitted to a Japanese diagnostic laboratory between October 2022 and March 2026. A total of 737 isolates were recovered, with Staphylococcus pseudintermedius (248/737, 33.6%) and Streptococcus canis (116/737, 15.7%) the most common isolates. Notably, 100 (40.3%) of the S. pseudintermedius isolates were methicillin-resistant. Cefotaxime demonstrated high activity against major Gram-positive pathogens, except for methicillin-resistant S. pseudintermedius, and Escherichia coli. In contrast, susceptibility to gatifloxacin varied markedly among the species, whereas the spectrum of gentamicin and polymyxin B was limited due to intrinsic resistance among common Gram-positive pathogens. These findings provide useful information for empirical antimicrobial selection in canine ocular infections in Japan.

The Na⁺/Ca²⁺ exchanger (NCX) is a key regulator of intracellular Ca²⁺ homeostasis, mediating bidirectional ion transport in response to electrochemical gradients. NCX plays essential roles in diverse physiological processes, including cardiac contraction, neuronal signaling, and hormone secretion, while its dysregulation is implicated in a wide range of pathophysiological conditions such as heart failure, ischemia, and neurodegenerative diseases. Recent advances in structural biology, particularly cryo-electron microscopy, have provided detailed insights into the molecular architecture of eukaryotic NCX, revealing the mechanisms underlying ion transport, regulation, and inactivation. These studies have highlighted the functional importance of conserved structural elements, including the α1- and α2-repeats and cytosolic regulatory domains, in governing exchanger activity. In parallel, pharmacological studies have identified a variety of NCX modulators with distinct mode and isoform selectivity. While classical inhibitors predominantly target the reverse mode, emerging compounds—including highly selective inhibitors and novel activators—demonstrate diverse mechanisms of action, often involving allosteric modulation rather than direct interaction with the ion-binding site. This review integrates current knowledge of NCX structure, function, and pharmacology, with a particular focus on the relationship between structural determinants and transport mode selectivity. We also discuss the challenges that have limited the clinical translation of NCX-targeting drugs and outline future perspectives for the rational design of next-generation NCX modulators.

European foulbrood, caused by Melissococcus plutonius, is a major bacterial disease of honey bee brood. Although strains belonging to the genetically related group known as clonal complex 12 (CC12) are highly virulent, their virulence factors remain unclear. Since tyramine has been proposed as a putative virulence factor, we constructed a knockout mutant of the putative tyrosine decarboxylase gene (tdc) from a CC12 strain to assess its role in pathogenicity. The tdc knockout mutant lost the ability to produce tyramine, confirming that tdc is responsible for tyramine production. However, the mutant showed no attenuation in virulence toward honey bee brood. These results suggest that tyramine production is not essential for the pathogenicity of CC12 strains in European foulbrood.

Hepatic copper accumulation is assessed qualitatively via histopathology, and hepatic copper concentration is measured quantitatively. Laparoscopic biopsy provides samples adequate for histopathology; however, its suitability for copper quantification in cats remains unclear. Liver tissue samples from 19 cats undergoing laparoscopic liver biopsy were evaluated for hepatic copper score and concentration. Copper scores were determined by a board-certified pathologist using rhodanine-stained sections. Hepatic copper concentrations were determined using atomic absorption spectrometry, and the rhodanine-positive pixel ratio was calculated from histological images using ImageJ. Copper-associated hepatopathy was identified in three cats: two with a score of 4 and one with a score of 5. Seven cats demonstrated cholangiohepatitis (scores 0–3). The hepatic copper score was significantly correlated with copper concentration in the 19 cats (Spearman’s r=0.757, P<0.001). Rhodanine-positive pixel ratio also correlated with copper concentration (Spearman’s r=0.668, P<0.01). Therefore, laparoscopic biopsy provides feline liver tissue feasible for qualitative and quantitative copper analysis. The liver rhodanine-positive pixel ratio offers a useful quantitative alternative when hepatic copper concentration cannot be measured in cats.

Ductal tumors of canine mammary glands can be difficult to distinguish from simple tumors on routine histology. Because oxytocin receptor (OXTR) expression in myoepithelial cells has been implicated in human breast tumorigenesis, we immunohistochemically evaluated 8 ductal adenomas and 5 ductal carcinomas, including OXTR expression. Luminal cells were positive for cytokeratin 19 and pan-cytokeratin. Suprabasal myoepithelial cells were strongly positive for p63, weakly and focally positive for vimentin, and negative for smooth muscle actin and calponin, therefore indicating that p63 is the most suitable marker for these cells in ductal tumors. Unlike humans, OXTR was expressed in luminal cells of normal canine mammary ducts and in both luminal and suprabasal myoepithelial cells in ductal tumors, suggesting a role in ductal tumor development.

A 5-year-old Poodle presented with a plantigrade stance three weeks after traumatic gastrocnemius tendon rupture. Surgical exploration confirmed a complete rupture; following debridement and tenorrhaphy, a 20-mm defect remained. This gap was bridged using a double-layer ultra-high-molecular-weight polyethylene (UHMWPE) suture tape and augmented with flexor digitorum lateralis (FDL) transposition. At 2 months, ultrasonography confirmed maintained tendon continuity without foreign body reaction. By 3 months, posture normalized and gait analysis showed near-symmetric hindlimb loading. No major complications occurred during the 12-month follow-up. Combined UHMWPE bridging and FDL augmentation is an effective surgical option for chronic gastrocnemius ruptures with substantial defects when primary apposition is not feasible.

This study investigated the timing of puberty and seasonal changes in spermatogenesis in raccoons (n=156) from Wakayama Prefecture. In the 0-year class, testis size, weight, and seminiferous tubule diameter increased in winter, although only a few raccoons were sexually mature. Most raccoons in the 1-year class attained sexual maturity by autumn–winter of their second year. In the ≥2-year class, testicular activity regressed during summer. Spermatogenesis scores were used to assess age-dependent spermatogenic development. Logistic regression indicated that testes with epididymides ≥19.1 mm in size and ≥9.6 g in weight corresponded to a 50% predicted probability of the presence of morphologically mature spermatozoa. These findings provide region-specific indices of male reproductive cycles in raccoons.

Understanding the underlying issues related to animal transport is essential for promoting animal welfare. However, no research has focused on the transport process and its physiological effects on spent layer breeder chickens. Therefore, this study aimed to investigate a single commercial transport process in spent layer breeder chickens and evaluated its physiological and behavioral effects across three strains of focal hens: Sakura, Lohmann Julia (Julia), and Hy-Line Brown (Brown). A total of 1,611 chickens (1,547 hens and 64 roosters, aged 700 days) including various crossbreeds and lineages were transported over 32.9 km in 55 min. The total mortality rate was 0.25%. Each chicken was sequentially housed in two transport crate types and remained there until shackling. The maximum duration from initial capture to shackling was 7 hr 30 min. Temperatures inside cages and crates were higher than ambient conditions. Transported focal hens showed reduced body weight and elevated heterophil-to-lymphocyte ratios. Brown hens exhibited higher heterophil-to-lymphocyte ratios and lower core body temperatures compared to the overall mean. Additionally, transported focal hens exhibited wet plumage, shivering, and piloerection due to rain exposure, although temperatures near them remained within their thermal comfort zone. These findings reveal the complexity of the transport process and its adverse effects on spent layer breeder chickens, highlighting genetic differences among strains in physiological and behavioral responses. They also underscore the need for careful animal monitoring, preventing wetting, and adopting strain-specific transport management practices to improve animal welfare.

A 5-month-old Munchkin cat was referred for hematuria. Computed tomographic angiography revealed hepatic arteriovenous malformation (HAVM) within the left lateral liver lobe and multiple acquired portosystemic shunts (APSSs), in addition to a bladder calculus. Following medical management, the cat underwent attenuation of arterioportal communications. Because ligation of the left hepatic artery did not normalize portal pressure, the left hepatic division was resected. Surgical ligation of a subset of the APSSs was performed 1 month later. Postoperatively, clinical signs improved, hepatopetal portal flow was restored, and biochemical liver function parameters normalized. The remaining APSSs regressed spontaneously. To our knowledge, based on the English-language literature, this is the first reported case of feline or canine HAVM in which liver function parameters normalized.

Porcine circovirus type 2 (PCV2) is the major causative agent of porcine circovirus-associated disease. We investigated the dynamics of maternally derived anti-PCV2 antibodies (MDA) in 40 piglets born to five healthy, unvaccinated sows on a Japanese swine farm. Anti-PCV2 antibody levels were measured by ELISA from birth to 19 days of age and analyzed together with serum total protein and IgG concentrations. Data were stratified by sow, and uncertainty was estimated using sow-cluster bootstrap analysis. The S/P ratio increased after colostrum intake, peaked at 1–3 days of age, and then declined exponentially until day 19. These findings characterize pre-vaccination anti-PCV2 MDA kinetics and indicate that serum total protein at birth may reflect passive immune status.

Leucocytozoon spp. are common avian haemosporidian parasites that can cause clinical symptoms with lethal cases in poultry worldwide. However, leucocytozoonosis has not been reported in domestic ducks (Anas platyrhynchos domesticus) in Japan. Two adult domestic ducks maintained in a zoological garden in Japan became lethargic, exhibited labored breathing, and died in July 2024. These ducks had hemorrhages in the visceral organs with splenomegaly and hepatomegaly. Megaloschizonts of haemosporidia were histologically observed in the spleen and other organs. Partial sequences of Leucocytozoon mitochondrial cytochrome b gene DNA were determined and classified as lineages known to infect wild waterfowl (Anseriformes). To the best of our knowledge, this is the first known fatal case of leucocytozoonosis in domestic ducks in Japan.

Serum amyloid A (SAA) is a major acute-phase protein in cats; however, the agreement between commercially available feline SAA assays has not been fully evaluated. This study compared two analytical systems: the FUJI DRI-CHEM vf-SAA (sandwich fluorescence immunoassay) and VET-SAA Eiken (immunoturbidimetry). Eighty residual plasma samples from client-owned cats were analyzed. Methods were compared using Spearman’s correlation, Passing–Bablok regression, and Bland–Altman percentage difference analysis. These assays revealed a strong association (Spearman’s ρ=0.948). Passing–Bablok regression indicated proportional and constant bias (y=0.3325x + 1.155), and Bland–Altman analysis demonstrated a large negative mean percent difference (−86.2%). These findings suggest that the results are not interchangeable and method-specific reference intervals may be required.

The African grey parrot (Psittacus erithacus) is endangered due to habitat loss, poaching, and illegal trade. In 2022, Chubu University and the Uganda Wildlife Education Centre–Conservation Area (UWEC-CA) have initiated an ex-situ conservation project for rehabilitation and future reintroduction. Noninvasively genetic sampling was conducted using feces from four parrots at UWEC-CA and naturally shed feathers from 22 parrots at 11 Japanese zoos. Non-invasive genetic sampling enabled reliable sex identification and mitochondrial sequencing of parrots in Uganda and Japan. Phylogenetic analysis revealed two major clades, including a Gabon-associated lineage within which all UWEC-CA parrots clustered, providing baseline genetic context relevant to ex-situ conservation management and evidence-based reintroduction.

Canine pulmonary adenocarcinoma (CPAC) is a rare, aggressive tumor with no established prognostic molecular biomarkers. The expression of monocarboxylate transporter 4 (MCT4) and glucose transporter 1 (GLUT1), key glycolysis-related proteins, is induced by hypoxia and is generally associated with poor prognosis in human pulmonary adenocarcinoma; however, their clinical significance in dogs remains unclear. This study investigated the expression of MCT4 and GLUT1 in 61 CPAC cases. Immunohistochemistry revealed significantly higher MCT4 and GLUT1 expression in tumors compared with normal lung tissues. High expression of both proteins was associated with lymph node metastasis. Kaplan–Meier analysis showed that high MCT4 expression was associated with prolonged overall survival, while GLUT1 showed no prognostic impact. However, MCT4 was not retained as an independent prognostic factor in multivariable Cox proportional hazards analysis. These results suggest that MCT4 and GLUT1 are upregulated in CPAC and may have distinct biological and clinical significance compared with human pulmonary adenocarcinoma.

Autism spectrum disorder (ASD) affects about 1 in 100 people worldwide, yet its causes remain poorly understood. Environmental factors, such as perinatal lead (Pb) exposure, have been linked to neurodevelopmental disruption, especially during periods when the blood-brain barrier is immature. This study aimed to assess ASD-like behavioural outcomes in offspring following maternal Pb exposure during neurodevelopment using a C57BL/6J mouse model. Pregnant dams received 100 ppm Pb acetate in their drinking water from the second week of gestation until weaning; controls were given deionised distilled water. Male offspring underwent behavioural assessments at 5 and 9 weeks of age using the three-chambered Social-Nonsocial (S-NS) interaction test and the Morris water maze. Pb concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS), and real-time PCR was used to target Shank3, an ASD-associated gene. Lead concentrations were significantly elevated in the blood, brain, bone, liver, and kidney of exposed offspring, confirming effective maternal-foetal Pb transfer. However, no significant differences were observed between groups in behavioural performance or Shank3 expression. These findings suggest that perinatal Pb exposure at 100 ppm in the last trimester of pregnancy, under the conditions tested, does not induce measurable ASD-like phenotypes in male C57BL/6J mice. Further studies are warranted to investigate dose-dependent effects, sex-specific vulnerabilities, and the broader molecular pathways involved.

Aquaporins (AQPs) are membrane proteins that facilitate the transport of small molecules such as water, glycerol, and urea. In mammals, 13 AQP isoforms (AQP0 to AQP12) exhibit tissue-specific expression. Over the past two decades, aquaporins (AQPs) have received considerable attention for their role in tumor biology. Squamous cell carcinoma (SCC) originates from stratified squamous cells and commonly affects the skin and oral cavity. SCC is prevalent in dogs and cats; however, no studies have reported an association between SCC and AQPs in these species. This study investigated the immunohistochemical expression of AQP1, AQP3, AQP5, E-cadherin, and Ki-67 in cutaneous and oral SCCs of dogs and cats. AQP1 and AQP5 were not expressed in tumor cells. In contrast, AQP3 and E-cadherin localized to the plasma membrane, primarily within island-like structures in both cutaneous and oral SCCs. Ki-67-positive cells appeared in small group and cord structures within tumor regions exhibiting reduced AQP3 expression. Therefore, AQP3 expression may be down-regulated in malignant tumor cells in SCCs of dogs and cats. These findings indicate that AQP3 may serve as a novel biomarker for assessing malignancy in SCCs of dogs and cats.

The thyroid gland is a highly vascularized organ in vertebrates. However, the information on the vascular pattern of this gland in pigs remains limited. This study elucidates the morphoanatomy and arterial supply of the gland in three breeds: Landrace (L), Large White (W), and Crossbreed (LWD). Two hundred twelve pigs were used and dissected to observe the arteries supplying blood to the gland. As a result, the gland was classified into three types based on its appearance: pear-shaped, butterfly-shaped, or partially separated. Moreover, the arteries supplying the gland were observed and then compared among breeds. The arterial supply of the thyroid gland on the cranial side consisted of branches from the cranial laryngeal artery, cranial thyroid artery, superficial cervical artery, and common carotid artery. Otherwise, the caudal side was supplied by the caudal thyroid artery, superficial cervical artery, bicarotid trunk, internal thoracic artery, and external thoracic artery. Furthermore, significant differences were identified between L and LWD, as well as between W and LWD, in the pattern of arterial origin on the cranial right side of the thyroid gland. Similarly, on the left side, significant differences were observed not only between L and W but also between W and LWD. On the caudal side, significant differences were found between L and W, as well as between W and LWD. These anatomical variations provide important insights for research and clinical applications involving the thyroid gland in pigs.

The glottis of 26 dogs with respiratory signs was examined by virtual laryngoscopy for peering into the throat from within the trachea (RDVL: rostral direction virtual laryngoscopy) with and without sedation of butorphanol, medetomidine, and alfaxalone (BMA). These dogs are divided into two groups of with or without sedation. In 9 unsedated dogs, there were many Chihuahuas, and the primary symptom was coughing. In 17 sedated dogs, Toy Poodles and Pomeranians were the most common breeds, and the primary symptoms were coughing and worsening respiratory symptoms at excitement. RDVL provided a reliable view of glottic motion, and the airway space was interfered with for flaccid adductors. RVDL without sedation is recommended. However, BMA sedation is suggested when necessary.

Branching patterns of the adrenal artery exhibit interspecies and individual variations. As Eulipotyphla species have distinctive morphological characteristics, observations in this group may provide insights into the comparative anatomy of this artery. This study used 15 house musk shrews (Suncus murinus). In most cases, adrenal arteries arose from a single parent artery, namely the caudal phrenic artery, abdominal aorta, or renal artery. In one left case, adrenal arteries emerged from both the abdominal aorta and renal artery. The most common pattern of adrenal arterial supply was one middle and one caudal adrenal artery on both sides, with no cranial one. The house musk shrew exhibited a simpler branching pattern than other species, offering comparative anatomical insights into the adrenal artery.

Ticks harbor diverse Rickettsia spp., including several spotted fever group rickettsiae of veterinary and public health importance. However, information on tick-associated Rickettsia spp. in Zambia remains geographically limited. In this retrospective molecular survey, we examined 1,587 individual ticks collected from vegetation and domestic animals in eight provinces of Zambia during 2016–2018. Ticks were identified morphologically and screened for Rickettsia spp. by PCR targeting the citrate synthase gene (gltA). Representative gltA positive samples were further characterized by sequencing of ompA, ompB, htrA, sca4, and the 16S rRNA gene. In total, 204 ticks (12.9%) were tested positive for gltA and detected in all eight provinces examined. Sequencing of gltA revealed 26 sequence variants, of which 25 clustered within the spotted fever group and one belonged to transitional group rickettsiae. Multilocus phylogenetic analysis identified sequence variants related to recognized or putative tick-borne rickettsiae, including R. africae, R. conorii, R. massiliae, R. aeschlimannii, Candidatus R. jingxinensis, Candidatus R. rhabdomydis, and R. hoogstraalii. These findings indicate that ticks in Zambia harbor genetically diverse Rickettsia lineages and provide a geographically broad molecular baseline for future surveillance, isolation attempts, and genomic characterization of tick-borne rickettsiae in the region.

Musladin–Lueke syndrome (MLS) is an inherited connective tissue disorder in Beagle caused by a homozygous missense mutation in the ADAMTSL2 gene. It is rare, but recognized globally. This report presents the first case in Japan definitively diagnosed via genetic testing. The 6-month-old male Beagle exhibited characteristic "tiptoe" gait, joint stiffness, lateral deviation of the eye socket, and undescended testes. At 10 months of age, bilateral Cryptorchidectomy was performed, and echocardiography revealed no abnormalities. At 12 months of age, the patient demonstrated progressive forelimb stiffness, chronic digital abrasions, and mild left atrial enlargement on echocardiography. As no curative treatment exists, we implemented symptomatic management using custom-made orthotic boots, which significantly improved the patient’s quality of life. The high probability that this condition remains underdiagnosed in Japan underscores the necessity to raise awareness among veterinary clinicians.

Neoplasia-related extrahepatic biliary obstruction (EHBO) is rare in dogs. An 11-year-old spayed mixed-breed dog had intermittent jaundice for several months. Imaging showed a lesion extending from the distal common bile duct to the major duodenal papilla. To relieve EHBO, transduodenal ampullectomy was performed, followed by partial duodenectomy including the papillary orifice and cholecystoduodenostomy. Histopathological examination revealed ampullary adenocarcinoma with invasion into the duodenal muscularis propria; margins were tumor-free. At >2 years after surgery, metastasis was not detected, and the dog remained clinically well. To our knowledge, this is the first report of canine ampullary carcinoma, suggesting that transduodenal ampullectomy can be useful for both palliative biliary decompression and the assessment of invasion depth to guide subsequent definitive surgery.

Squirrels (family Sciuridae; hereafter referred to as sciurids) are frequently treated with veterinary medical products, such as fipronil, a topically applied insecticide used for ectoparasite control; however, fundamental information on their drug-metabolizing capacity remains limited. In this study, we examined whether hepatic cytochrome P450 (CYP) profiles and microsomal fipronil metabolism differ among sciurids, Eurasian red squirrel (Sciurus vulgaris orientis), Siberian flying squirrel (Pteromys volans orii), Pallas’s squirrel (Callosciurus erythraeus), and laboratory rodents (Mus musculus and Rattus norvegicus). We integrated sequence, expression, and functional analyses with a primary focus on CYP2C and CYP3A, key enzymes involved in xenobiotic metabolism. No clear evidence of sciurid-specific loss or major divergence was detected in CYP2C/3A, and microsomal fipronil metabolic efficiency did not differ significantly among the examined species. RNA sequencing (RNA-Seq) revealed distinct hepatic CYP expression profiles beyond CYP2C/3A; notably, CYP2B represented <1% of total major CYP expression in the Eurasian red squirrel, a proportion lower than that observed in laboratory rodents. These findings provide baseline information on hepatic CYP profiles and microsomal fipronil metabolism in sciurids and may support future comparative studies of wildlife drug metabolism.

An 11-month-old neutered male mixed-breed cat was presented to the referring hospital with the chief complaint of progressive ataxia. Magnetic resonance imaging (MRI) revealed a well-defined, ovoid, solitary mass on the left side of the fourth ventricle. Immunostaining of surgically excised tissue led to a diagnosis of feline infectious peritonitis (FIP). To our knowledge, this is the first report of a central nervous system (CNS)-FIP presenting as a solitary fourth ventricular mass identified by MRI. CNS-FIP should be considered as a differential diagnosis when encountering cases of young cats with a solitary mass lesion in the fourth ventricle.

Although orthovoltage radiation therapy remains widely used in veterinary medicine in Japan due to its affordability and operational simplicity, accurate calculation of dose distribution is challenging. Treatment planning varies between practitioners and tends to rely on empirical methods. This study aimed to compare the effects of three different orthovoltage beam directions on dose distribution in feline nasal lymphoma using Monte Carlo simulations. CT images from five clinical cases were analyzed using three irradiation plans: Plan A (beam directed perpendicularly to the hard palate), Plan B (perpendicularly to the nasal bridge), and Plan C (from the oral cavity). Each plan used a 4 × 4 cm field and delivered a 10 Gy dose at 280 kVp. Doses to the tumor, brain, and both eyes were calculated. Mean dose for the tumor did not significantly differ among the three plans. Plan B resulted in significantly higher doses to the ipsilateral eye compared to Plan C, but delivered the lowest brain dose. Depth-dose analysis revealed a peak just above the bone at the beam entrance, followed by a sharp attenuation in all plans. These findings suggest that beam direction substantially affects dose distribution in orthovoltage therapy, particularly for organs at risk including superficial bones and overlying skin. Meticulous planning is essential to ensure sufficient tumor dose coverage while mitigating and distributing adverse effects, especially in complex regions like the feline nasal cavity.

Exfoliative toxins (ETs) produced by staphylococci primarily target and cleave desmoglein 1 (Dsg1), a desmosomal adhesion molecule expressed in stratified squamous epithelia. A new ET gene was recently discovered in Staphylococcus felis, a commensal and opportunistic pathogen responsible for skin infections in Felidae. This study focused on characterizing ExfA, a protein encoded by this novel S. felis ET gene, examining its enzymatic characteristics, pathogenic potential, and prevalence. Recombinant ExfA eliminated immunofluorescence for Dsg1, but not for Dsg3, in the feline epidermis and directly digested the baculovirus-expressed extracellular segment of feline Dsg1. Additionally, recombinant ExfA digested mouse Dsg1α and Dsg1β, and when injected into neonatal Slc:ICR mice, caused superficial epidermal splitting. Molecular modeling and docking analyses indicated that ExfA forms a closed oxyanion hole and is predicted to interact with the substrate in a manner similar to that of serine proteases. An epidemiological survey of feline skin isolates in Japan found that 46.7% of S. felis clinical isolates contained exfa, and culture supernatants from 71.4% of exfa-positive isolates digested feline Dsg1. In summary, S. felis ExfA demonstrates enzymatic activity that can degrade feline Dsg1, is frequently found in cat-derived S. felis strains, and may play a role in colonization and invasion of feline skin.

This study evaluated the utility of meat juice (MJ) from market-purchased pork in Japan and Vietnam for serological surveillance of mosquito-borne viruses, specifically Japanese encephalitis virus (JEV) and Getah virus (GETV). We confirmed the presence of specific antibodies against JEV and GETV in the MJ samples using enzyme-linked immunosorbent assay and virus neutralization test. The lack of correlation between JEV- and GETV-specific optical density values suggests independent infections in Vietnamese pig populations. The high seroprevalence observed in Vietnam highlights the practical utility of MJ as a viable alternative to serum for effective large-scale arboviral surveillance in field settings. These findings underscore the need for comprehensive mosquito-borne virus control in swine health management.

Hypoxia-inducible factor–prolyl hydroxylase (HIF-PH) inhibitors stimulate endogenous erythropoietin (EPO) production and are used for the treatment of anemia of chronic kidney disease (CKD) in humans. In veterinary medicine, molidustat (MOL) has demonstrated acceptable safety and efficacy with anemia of CKD in cats. Roxadustat (ROX) is another HIF-PH inhibitor that has a longer half-life than MOL, allowing for less frequent dosing. Therefore, ROX may offer an advantage in improving medication adherence. However, the safe dose range and erythropoietic effects of ROX in cats remain unclear. In the present study, an exploratory pharmacokinetic analysis of single-dose ROX administration was conducted in healthy cats to assess its safety and erythropoietic effects. In addition, a repeated-dose study was performed to evaluate safety and tolerability during continued administration. In the single-dose study, no apparent adverse events were observed at doses ≤20 mg/kg; however, severe adverse events including vomiting and systemic clinical signs leading to death were observed at 80 mg/kg, indicating that high-dose administration should be avoided. Following ROX administration, increases in reticulocyte counts and serum EPO concentrations were observed, suggesting erythropoietic activity in cats. In the repeated-dose study, ROX administered at 5–8 mg/kg for six weeks was not associated with apparent adverse events based on clinical condition and complete blood count. These results suggest that this dose range may serve as a candidate for future clinical evaluation in CKD cats.

Carriage of antimicrobial-resistant bacteria in wildlife is a growing public health concern. We isolated an extended-spectrum β-lactamase-producing Escherichia coli from the feces of a wild bear collected in a persimmon orchard in 2025. The bear isolate exhibited resistance to ampicillin, cefazolin, cefotaxime, tetracycline, and chloramphenicol. Whole-genome sequencing revealed that the strain belonged to ST5044-OUT:H29 and harbored the bla_CTX-M-55 and other resistance genes integrated into the bacterial genome. Comparative genomic analysis showed close relatedness to isolates from a Vietnamese pig farmer and a Japanese slaughterhouse wastewater, with pairwise distances of 0–80 single-nucleotide polymorphisms. DNA metabarcoding revealed a diet dominated by wild vegetation, with a minor anthropogenic plant component. Thus, wild bears may contribute to the dissemination of antimicrobial-resistant E. coli at the human–wildlife interface.

Hemilaminectomy is the most common surgical procedure for type I thoracolumbar intervertebral disk herniation (TL-IVDH). Despite the clinical relevance of postoperative morphological assessment to predict postoperative complications, only a few studies have evaluated long-term changes at the surgical site, such as those affecting the spinal cord and vertebrae, after hemilaminectomy for type I TL-IVDH. This retrospective study describes postoperative changes at the surgical site, including disk height, in dogs that had undergone hemilaminectomy and subsequently experienced late recurrence. 19 dogs were eligible for inclusion in this study. The disk height index (DHI) at the initial affected site was significantly reduced compared to the time of initial onset. The maximal spinal cord compression rate at the initial affected site at the time of recurrence decreased significantly compared to that at the time of initial onset. Two dogs had bone regrowth at the site of first surgery at the time of recurrence. No recurrence of disk herniation or spinal cord injury caused by bone regrowth was observed at the surgical site. In conclusion, structural changes such as decreased DHI and bone regrowth were observed at the surgical site a long time after hemilaminectomy, but these changes were not the direct cause of the neurologic signs observed at recurrence.

Contagious bovine pleuropneumonia (CBPP) is a severe respiratory disease of cattle caused by Mycoplasma mycoides subsp. mycoides (Mmm). A method combining PCR and restriction enzyme analysis (PCR-REA) is described in the World Organisation for Animal Health manual to differentiate Mmm from the related species Mycoplasma mycoides subsp. capri. However, the primers in the manual did not amplify the target region from an attenuated Mmm strain. Genome sequence comparison revealed mismatches between the primers and the target sequences of Mmm strains. Newly designed primers with corrected bases successfully amplified the target region from M. mycoides strains, and REA patterns distinguished the two subspecies. These results indicate that the new primers provide reliable Mmm detection and enhance preparedness for future CBPP outbreaks.

This study was conducted to characterize the spatial epidemiology and socio-economics of bovine brucellosis on dairy farms in the Kilinochchi and Mullaitivu Districts of Northern Province, Sri Lanka. A cross-sectional study involving bulk milk sampling and interviews using a structured questionnaire was conducted at 214 dairy farms. Milk samples were tested for Brucella antibodies using an indirect enzyme-linked immunosorbent assay. Global spatial clustering statistics and SaTScan were also performed. The association between milk sero-positivity and socio-economic variables was evaluated using univariable analysis. Multi-variable spatial risk factor analysis was conducted using the integrated nested Laplace approximation selecting principal components (PCs) of land use and socio-economic and ecological variables with P<0.2 in the univariable analyses as explanatory variables. The crude and true herd-level prevalence was estimated at 12.1% (26/214; 95% confidence interval [CI]: 8.4–17.2%), and 11.2% (95% CI: 7.3% to 16.3%), respectively. The Cuzick and Edward’s k-nearest neighbor test found significant clustering at 8, 10, and 11 nearest neighbors; however, no local cluster was suggested by SaTScan. In the final multivariable model, the PC representing agricultural land as positive loading and forest land as negative was positively associated with brucellosis sero-positivity, whereas barn cleaning was negatively associated, suggesting good farm hygiene is important for preventing bovine brucellosis.

This study investigated breed-related differences in renal biomarkers in clinically healthy dogs, with a focus on Shiba Inu. Serum symmetric dimethylarginine (SDMA), creatinine, and cystatin C concentrations were measured in 23 Shiba Inu and 36 dogs of other breeds. Serum SDMA concentrations were significantly higher in Shiba Inu compared to other breeds. The median serum SDMA concentration (12.3 vs 9.5 μg/dL) and reference intervals (8.3–18.4 vs 4.4–14.6 μg/dL) in Shiba Inu were higher than those in other breeds. Serum creatinine concentrations were also higher in Shiba Inu, whereas no consistent differences were observed in serum cystatin C concentrations when body weight was partially matched between groups. These findings suggest that Shiba Inu may have a tendency toward higher SDMA and creatinine concentrations; therefore, when evaluating renal function in this breed, these biomarkers may need to be interpreted cautiously and in conjunction with other clinical assessments.

A 13-year-old Chihuahua presented with a distal forelimb soft tissue sarcoma and underwent surgical excision. To close the resulting large skin defect, a two-stage approach was performed using a basic fibroblast growth factor (bFGF)–impregnated artificial dermis composed of collagen gelatin sponge (CGS), followed by application of an acellular fish skin graft (FSG). After 10 days of bFGF-impregnated CGS application, uniform granulation tissue had formed, and an FSG was subsequently applied. Complete epithelialization was achieved 25 days after FSG placement without additional grafting. At 320 days postoperatively, no postoperative complications or local recurrence were observed. However, given the potential risk of promoting residual tumor cell proliferation, local bFGF use in malignant tumor-associated wounds should be restricted to carefully selected cases.

A 16-day-old male Japanese Black calf affected by skeletal dysplasia, a recessive genetic disorder characterized by marked enlargement of the limb joints due to epiphyseal enlargement. Histological examination revealed chondrocyte proliferation in both the humeral and femoral growth plates, with disorganized chondrocyte alignment and fewer bone trabeculae observed in the humerus. These findings suggest that the morphological changes of chondrocytes may be imbalanced during endochondral ossification at the growth plate. Joint enlargement was evident in the epiphyseal region at birth, despite the absence of articular chondrocyte hyperplasia. Although the details of the pathological mechanism remain unclear, cartilaginous epiphysis overgrowth during embryonic development or secondary ossification center expansion during endochondral ossification may cause the joint enlargement observed in this genetic disorder.

This study examined the impact of passive immunity at the herd level on survival probability during the first year of life for successful passive immunity (SPI) farms (n=19), < 20% of the proportion of newborn calves with serum immunoglobulin (Ig) G concentrations of < 10.0 g/L, and failure of passive immunity (FPI) farms (n=20) with ≥20%. The proportions of serum IgG concentrations on SPI farms were clearly shifted toward the high-concentration strata compared with FPI farms. SPI farms showed significantly (P<0.001) higher survival probability than FPI farms. These results suggest that having the proportion of higher serum IgG concentrations at the herd level may increase survival probability.

Maternal cells and antibodies are present in equine colostrum, but their relationship with immune cells in foals after colostrum ingestion remains unclear. This study longitudinally analyzed immune cells in the peripheral blood of neonatal foals at short intervals and investigated their relationship with colostral immune cells. Eleven clinically healthy draft mares and their foals were examined. Foal blood was collected before colostrum intake (0 hr) and at 2–3, 6, 12, 36–48 hr, and 3 and 7 days after ingestion. Mare blood and milk (0, 36–48 hr; 0 hr milk defined as colostrum) were also collected. Mononuclear cells were analyzed by flow cytometry using cluster of differentiation (CD)5, CD4, CD8, CD21, CD172a, and CD45RO, with double-staining for major histocompatibility complex class II (MHC II). Total leukocytes and CD4⁺, CD5⁺, CD8⁺, and CD45RO⁺ cells significantly increased during the first week of life, whereas MHC II⁺ CD5⁺, MHC II⁺ CD8⁺, and MHC II⁺ CD45RO⁺ cells increased earlier at 12 hr. CD5⁺, CD4⁺, and CD8⁺ cells were more abundant in colostrum than in milk. CD8⁺ cells were more abundant in colostrum than in blood, whereas CD21⁺ and CD45RO⁺ cells were more abundant in blood than in colostrum, with no correlation. An early increase in CD8⁺ MHC II⁺ T cells before gut closure is a novel finding and suggests possible migration of colostrum-derived CD8⁺ T cells into neonatal circulation.

A 10-year-old cat presented with a 2-year history of nasal discharge, sneezing, and nasal planum swelling. Granulomatous rhinitis caused by Prototheca wickerhamii infection was diagnosed on the basis of histopathological and genotypic analyses of biopsy samples. Oral voriconazole was administered; however, it caused adverse effects and was discontinued. The lesion, initially localized to the nasal planum, progressively extended into the nasal cavities, destroying the cribriform plate and orbital bone and invading the orbit and olfactory bulb. Following local voriconazole injection into the lesion, neurological impairment associated with increased intracranial pressure was observed. Despite transient resolution of clinical signs after resumption of voriconazole administration via a gastrostomy tube, the cat died from disease progression 465 days after the initial visit.