Journal of Veterinary Medical Science最新文献

Chitin digestion in pangolins and other anteaters is thought to be aided by commensal bacteria in the digestive tract, in addition to their chitinase. This study characterized the gut microbiota of captive Javan pangolins using amplicon sequencing. Fecal samples were collected from two individuals and were sampled twice over one week. The dominant bacterial phyla identified were Firmicutes (Bacillota), Bacteroidetes (Bacteroidota), Proteobacteria (Pseudomonadota), and Actinobacteria (Actinomycetota). The most prevalent genera included Clostridium, Bacteroides, Lactobacillus, Bifidobacterium, Streptococcus, and Sporosarcina. Alpha and beta diversity were relatively low between paired samples, but the short sampling interval limits conclusions about microbial stability. These findings provide insights into the Javan pangolin's gut microbiota and support future research on microbial contributions to their digestion, health, and conservation.

Canine lymphoma is a common hematopoietic malignancy with limited therapeutic options, particularly in drug-resistant cases. Overexpression of Exportin 1 (XPO1) promotes oncogenesis by impairing the nuclear-cytoplasmic translocation of tumor suppressor proteins (TSPs). KPT-335 (Verdinexor), a selective XPO1 inhibitor, restores TSP function, inducing cell cycle arrest and apoptosis. In this study, we investigated the in vitro effects of KPT-335 alone and in combination with doxorubicin or vincristine in four canine lymphoma cell lines. KPT-335 reduced XPO1 protein expression in a dose-dependent manner, an effect reversed by proteasome inhibition, suggesting proteasome-mediated degradation. Combination treatments significantly suppressed cell proliferation compared with single agents. These findings highlight the preclinical evidence of combining KPT-335 with conventional chemotherapies in canine lymphoma.

Postoperative ileus (POI), commonly induced by intestinal manipulation (IM) during laparotomy, results in intestinal wall injury, inflammation, adhesion, and impaired gastrointestinal motility. This study evaluated the effects of mosapride citrate (Mos), a 5-HT₄ receptor agonist, and trehalose (Tre), a cytoprotective disaccharide, on gastrointestinal transit in an IM-induced POI mouse model. Mature male C57BL/6J mice were subjected to IM and allocated into five groups: IM + vehicle (control), IM + Mos (0.2 mg/kg, two times), IM + Tre (100 mg/kg, two times), IM + combined Mos & Tre, and IM + sequential Tre + Mos treatment. Gastrointestinal transit was quantified using phenol red method. All four treatment groups exhibited a significant increase in phenol red recovery in the lower small intestine compared with the control group (P<0.05). Notably, sequential administration (Tre + Mos) resulted in greater dye progression beyond the manipulated region than that of simultaneous (Mos & Tre) treatment (P<0.05). These findings suggest that although both agents individually promote gastrointestinal transit, the therapeutic effect is enhanced when Tre is administered first, followed by Mos. Thus, the timing and sequence of administration play a critical role in the treatment of POI. Sequential Tre + Mos therapy may represent a promising strategy for accelerating the functional restoration of gastrointestinal transit after intestinal injury.

Bovine respiratory disease syndrome, primarily caused by bovine parainfluenza virus type-3 (BPIV-3), is characterized by a high incidence in calves. However, despite its significant clinical importance, the codon usage patterns and evolutionary dynamics of BPIV-3 hosts remain elusive. Hence, this study aimed to systematically analyze the codon usage bias of the BPIV-3 structural protein gene HN, and the roles of mutational pressure and natural selection in its evolution were evaluated. Herein, analysis of indicators such as effective codon number (ENC), relative synonymous codon usage, and codon adaptation index revealed a low codon bias for BPIV-3, with codon preferences showing significant differences from the host. Notably, ENC-GC content at the third codon spot analysis indicated that natural selection dominated codon usage. Additionally, phylogenetic analysis divided BPIV-3 into three main genotypes (namely a, b, and c), with genotype C exhibiting a higher codon adaptability to the host. Altogether, these findings reveal the host-BPIV-3 evolutionary interaction mechanisms, providing a theoretical basis for vaccine design and epidemiological surveillance.

This study examined the effect of platelet-rich plasma (PRP) administration on the repair of articular cartilage damage in domestic pigs with experimentally induced leg weakness. The left hind stifle joints of six 56-day-old castrated domestic pigs were artificially injured; PRP was injected into the stifle joints of three pigs. Histopathological analysis of dissected articular cartilage revealed that all specimens were lightly stained with Alcian blue, and regions containing immature chondrocytes or chondrocyte clusters indicated cartilage repair. The average cartilage thickness was 189.44 μm in the control group and 386.53 μm in the treatment group, showing a significant difference (P≤0.028). These findings suggest that PRP administration promotes articular cartilage repair in domestic pigs.

C-telopeptide (CTX) fragments of type I collagen are widely used as markers of bone resorption in mammals. This study evaluated the performance of two enzyme-linked immunosorbent assays (ELISAs) using antibodies against different CTX epitopes-CTP-18 and CTP-8-in ovariectomized (OVX) mice, and examined the cross-species applicability of the CTP-18 ELISA in Pacific bluefin tuna (Thunnus orientalis). In OVX mice, both serum and urinary CTP-18 levels significantly increased compared to sham-operated controls (P<0.05), and were moderately correlated with deoxypyridinoline (DPD) levels and inversely with bone mineral density. In contrast, CTP-8 was less responsive. The CTP-18 antibody cross-reacted with mouse, rat, human, and tuna sera, and showed good dilution linearity in tuna samples. Tuna serum CTP-18 levels were positively correlated with DPD (r=0.82, P<0.05). These findings suggest that the CTP-18-based ELISA is a reliable tool for monitoring bone resorption not only in rodents but also in fish, providing a new approach for assessing skeletal turnover in aquaculture species.

Canine epitheliotropic cutaneous T-cell lymphoma (ECTCL) is a malignant neoplasm exhibiting various skin lesions. Metastasis to the lymph nodes and distant organs contributes to the poor prognosis of ECTCL; however, the underlying molecular mechanisms remain unclear. In the present study, the roles of chemokine receptors, such as CC chemokine receptor (CCR) 4 and CCR7, in the migration of tumor cells were examined using a canine cutaneous lymphoma model. Three mouse groups were prepared and xenografted with wild-type (WT), CCR4 knockout (KO), or CCR7KO canine ECTCL (EO-1) cells. The proportion of EO-1 cells in tissues and blood was significantly lower in the CCR4KO and CCR7KO groups than in the WT group. Only the iliac lymph node, a sentinel lymph node for the xenograft site, was enlarged with the infiltration of EO-1 cells in all groups. The size of the iliac lymph node was smaller in the KO groups than in the WT group. All mice developed a subcutaneous nodule at the xenograft site, which was smaller in the KO groups. In the cell proliferation assay, chemokine ligands stimulated an increase in EO-1 cells in the WT group, but not in the KO groups. These results suggest that CCR4 or CCR7 plays a vital role in the initial migration to sentinel lymph nodes and proliferation in a canine cutaneous lymphoma model.

A 5-month-old imported boar showed posterior paralysis upon arrival in Japan. Both limbs had coldness, algesia, and thigmesthesia. A thrombus was detected from the abdominal aorta to the left external iliac artery. Irregular vegetation was observed on the left atrioventricular valve. The skeletal muscles in the hind limb appeared like boiled meat. The histological diagnoses were endocarditis, glomerulonephritis, and meningoencephalitis with Gram-negative bacilli as well as diffuse intravascular coagulation and diffuse alveolar damage. The bacilli were identified as Actinobacillus suis via immunohistochemistry and 16S rRNA gene sequencing. This is the first case report of acute posterior paralysis due to iliac thromboembolism in swine with A. suis infection. Iliac thromboembolism should be considered if posterior paralysis is observed in swine.

Isoleucyl-tRNA synthetase 1 (IARS1) is essential for protein synthesis. Although IARS1 mutations cause growth and metabolic disorders in humans, its role in embryonic development remains unclear. We generated Iars1 knockout (KO) mice and observed complete absence of homozygous KOs among 44 pups, indicating embryonic lethality. A χ² test confirmed significant deviation from Mendelian ratios. At E12.5, multiple resorbed implantation sites were observed, and histology at E9.5 showed embryos lacking recognizable structures. Evidence of implantation (decidual swellings with residual trophoblast and maternal vasculature) indicates post-implantation survival but failure to progress beyond early organogenesis. These results demonstrate that IARS1 is indispensable for early mouse development and provide a useful model to study the link between IARS1 deficiency and disrupted organogenesis.

A 6-year and 11-months-old male striped skunk, Mephitis mephitis, showed inappetence and died. Necropsy revealed multiple hepatic masses, an enlarged spleen, wedge-shaped lesions in the kidneys, and a cervical cyst with white nodules. Histopathologically, the hepatic masses were diagnosed as biliary cystadenomas accompanied by chronic inflammation, the cervical cyst was a thymoma, and the splenic and renal lesions were diagnosed as infarctions. Amorphous eosinophilic material was observed in the liver, spleen, and kidney. These proteinaceous deposits were positive for Congo red staining with yellowish to green birefringence under polarized light. These deposits were immunohistochemically positive for amyloid A (AA). This report describes the pathological features of AA amyloidosis, biliary cystadenoma and cervical thymoma in a striped skunk.