Journal of Veterinary Medical Science最新文献

Amyloidosis is a disease caused by amyloid deposition and has been reported in various animal species; however, reports on Afrotherian species, including Cape hyraxes, are extremely limited. In this report, we describe the case of a 4-year-old captive Cape hyrax affected by amyloidosis. Histological examination revealed amyloid deposits in the liver, spleen, kidneys, and heart, which stained orange-red with Congo red and exhibited typical birefringence under polarized light. Mass spectrometry-based proteomic analysis and immunohistochemistry identified serum amyloid A in the amyloid deposits. Based on these findings, the case was diagnosed as amyloid A amyloidosis. This is a first case of amyloid A amyloidosis in Cape hyrax and, to our knowledge, the first documented case in any Afrotherian species.

The objectives of this study were (1) to confirm the expression of diamine oxidase (DAO) in the intestines of healthy calves immune-histologically and to clarify whether the expression of DAO in the intestines of calves with diarrhea differs from that of healthy animals, and (2) to clarify the relationship between DAO and intestinal inflammation using haptoglobin (HPT), a biomarker commonly used to evaluate inflammation. The abomasum, duodenum, jejunum and ileum, cecum, colon, and rectum of each animal were sampled at necropsy for immunohistochemical staining targeting DAO. DAO was diffusely expressed in all areas from the abomasum to the rectum in healthy calves, whereas its expression was reduced in calves with diarrhea. Four Japanese black calves with mild dehydration caused by diarrhea were included in the study to investigate the potential relationship between DAO and HPT. DAO activity was extremely low in diarrhea cases, whereas HPT levels were high. When an oral rehydration solution (ORS) was administered to these cases for three consecutive days, HPT significantly decreased logarithmically and fecal properties returned to normal on the fourth day of treatment. In contrast, DAO activities were significantly increased by oral rehydration therapy (ORT), and DAO activities were significantly negatively correlated with HPT concentrations. The present results confirmed that DAO is expressed in the epithelial cells of the intestinal mucosa in cattle, and that both the small and large intestines significantly contribute to blood DAO levels. Furthermore, DAO expression was reduced by enteritis.

An 11-month-old female kitten was evaluated for lameness and an inability to close her mouth. The kitten had marked hypocalcemia with elevated intact parathyroid hormone and 1,25(OH)₂D₃ levels. Radiographic imaging indicated generalized osteopenia and dysplasia of temporomandibular joints. Since a nutritionally complete diet was being fed, dysfunction of vitamin D receptors (VDR) was suspected. Genetic tests revealed three variants (c.439A >G, c.509C >T, and c.529_530insGCA) in the VDR gene, and c.509C >T, replacing proline 170 with leucine (p.Pro170Leu), was predicted to be damaging by in silico analysis. VDR-deficient feline kidney epithelial cells were transfected with wild-type or p.Pro170Leu VDR expression vectors, revealing impaired responsiveness to 1,25(OH)₂D₃ in mutants. Based on these findings, the cat was diagnosed with vitamin D-dependent rickets type 2.

The wall of eyeball limits the penetration of the common fixatives, raising inadequate fixation or degeneration of internal tissue and posing challenges for preparing thin sections of the whole eyeball. In addition, many formaldehyde-containing fixatives exhibit the strong cross-linking effect that can excessively mask antigenic epitopes, thereby hampering immunological analyses. This study tried to develop an available fixative that exerts high permeability to mouse whole eyeballs and applicability to immunostaining. Glyoxal is known to have milder cross-linking capacity compared to formaldehyde, bringing better preservation of epitopes. We substituted the formaldehyde component in Davidson's solution with glyoxal and supplemented 1-butanol, methanol, 2-mercaptoethanol, and tris (2-carboxyethyl) phosphine hydrochloride (TCEP-HCl). Using modified fixatives and the GBMT solution, which was named by the initial letters of each component listed above, mouse eyeballs were immersion-fixed with the modified fixatives, and both tissue morphology and immunostaining quality were evaluated. The results showed that the GBMT solution prepared with glyoxal and specific combinations of additives improved morphological preservation of the eyeball tissues and enhanced immunofluorescence signals for certain cytoplasmic antigens, compared to the standard Davidson's solution. Our findings demonstrated that the successful development of a novel fixative enables both high-quality whole eyeball sectioning and improved immunostaining performance through immersion fixation alone.

Inflammation is a fundamental defense mechanism in animals, and its accurate detection is essential for diagnosis and treatment in veterinary medicine. Serum amyloid A (SAA), an acute-phase positive protein (APP), is widely used to detect inflammation in domestic animals. However, its application in wildlife, particularly raccoon dogs (Nyctereutes procyonoides koreensis), remains underexplored. This study aimed to establish a reference interval (RI) for SAA in raccoon dogs and explore its applicability as a biomarker of inflammation. A total of 83 blood samples from 43 raccoon dogs collected from the Korean Wildlife Rescue Center were categorized into three clinical groups: clinically healthy (CH), mild injury (M), and severe injury (S). The SAA concentrations were significantly higher in the S group than in the CH and M groups, whereas no significant difference was observed between the CH and M groups. The RI for SAA in CH raccoon dogs was determined to be 0.13-1.4 mg/L. Although SAA may have limited sensitivity for detecting mild or localized inflammation, the results support its use as a reliable marker of severe inflammation in raccoon dogs. Future studies should explore other APPs to improve the diagnostic accuracy of inflammation in wildlife health assessment.

Cancer in dogs remains a major challenge in modern veterinary medicine. Immunotherapy using immune checkpoint inhibitors (ICIs) is available for various human tumor types, and recent veterinary clinical studies have shown that ICIs are a promising approach for treating canine cancers. A canine chimeric anti-PD-L1 antibody, c4G12 (HFC-L1), has been investigated for canine cancer immunotherapy; however, its clinical benefits have not been well characterized in tumors other than pulmonary metastatic (stage IV) oral malignant melanoma (OMM). To explore the efficacy and safety of HFC-L1, we conducted a clinical study in dogs with stage I-III OMM or other tumor types (n=12). HFC-L1 treatment at a dose of 5 mg/kg every 2 weeks was well tolerated, and no grade 3 or higher treatment-related adverse events were reported. Among the dogs eligible for response evaluation (n=10), a partial response was observed in one dog with squamous cell carcinoma, resulting in an objective response rate of 10%. In addition, in a dog with ceruminous cell carcinoma, clinical evidence of a tumor response was observed in metastatic lung lesions. Together, these results suggest that the HFC-L1 therapy is applicable for the treatment of various tumor types, although its clinical benefits should be further evaluated in clinical studies involving a larger number of dogs with each tumor type.

The Tokara horse is a breed of native Japanese horse, for which hematological and biochemical data are lacking. The aim of this study was to obtain current hematological and biochemical data on Tokara horses. We enrolled 90 Tokara horses kept at the Kaimon Foothills Nature Park (Kagoshima) that underwent physical examinations and blood sampling between 2022 and 2024. All horses in this study were regarded as clinically healthy, based on physical examinations. Hematological and biochemical parameters also showed no abnormal values. Based on the above results, we consider that the data from this study will serve as reference values for blood tests in Tokara horses. However, we consider further research is needed on horses kept at two other locations (Nakanoshima and Iriki farm, Kagoshima).

Osteoarthritis (OA) or degenerative joint disease (DJD) is a degenerative joint disease that progressively causes loss of joint function and is the most common and costly form of arthritis. Non-steroidal anti-inflammatory drugs (NSAIDs) are currently one of therapeutic treatment options for OA. Because NSAIDs do not alter the underlying pathophysiological process on the structural degradation of joint tissue but merely control signs of pain and inflammation, recent developments have allowed the use of treatments termed disease modifying osteoarthritic drugs (DMOADs) aimed at targeting the pathophysiologic processes of OA with the view of preventing, retarding progression of, or reversing morphologic changes associated with OA. Several in vitro and experimental studies have reported potential efficacy of glucosamine (GlcN) and pentosan polysulfate (PPS) as novel therapeutic agents of OA. This review will evaluate the clinical efficacy and safety of DMOADs with particular focus on GlcN and PPS based on the prescribed outcome measures by European Medicines Agency.

Supraventricular tachyarrhythmia (SVTA) in dogs can cause cardiac dysfunction and may progress to heart failure. Pimobendan, an inotropic agent with calcium-sensitizing and phosphodiesterase III inhibition, is widely used in veterinary medicine. However, its influence on myocardial injury under persistent SVTA remains incompletely understood. This study aimed to evaluate whether pimobendan improves systolic function without exacerbating myocardial injury, using a canine model of rapid atrial pacing (RAP). Fourteen healthy Beagle dogs were allocated to either a control or pimobendan group. RAP was performed for three weeks at 390 bpm. Cardiac function was assessed by echocardiography before (baseline) and after RAP (3W). Concurrently, cardiac troponin I (cTnI) concentrations were measured to assess myocardial injury. In the control group, a significant increase in cTnI was observed at 3W compared with baseline (0.023 ± 0.029 ng/mL vs. 0.176 ± 0.173 ng/mL). Additionally, in the control group, echocardiographic parameters worsened, including fractional shortening (FS) (37.8 ± 4.6% vs. 24.5 ± 6.8%) and stroke volume (SV) (15.8 ± 3.1 mL vs. 10.5 ± 2.0 mL) at 3W compared with baseline. In contrast, the pimobendan group showed no significant differences in these echocardiographic parameters. cTnI concentrations also remained within the normal range without significant differences. These results suggest that pimobendan preserved systolic function without aggravating myocardial injury during sustained SVTA. Pimobendan may therefore be safe and effective cardiac inotropic agent for the treatment of dogs with SVTA.

This study aimed to determine the effects of precentrifugation storage time and temperature on coagulation and fibrinolysis parameters in Japanese Black calves. Blood samples were collected from calves under 6 weeks of age into plastic tubes containing 3.2% sodium citrate. Whole blood was stored at either room temperature or under refrigeration prior to centrifugation. Prothrombin time, activated partial thromboplastin time, fibrinogen level, and antithrombin level were measured. The results indicated that plasma parameters in samples centrifuged within 9 hr of collection showed no more than ± 10% variation compared with those in samples centrifuged within 1 hr of collection.