Journal of Veterinary Medical Science

Tyramine, a trace monoamine produced from tyrosine by decarboxylation and found naturally in foods, plants, and animals, is a suspected virulence factor of Melissococcus plutonius that causes European foulbrood in honey bee brood. In the present study, we developed a method for quantitative analysis of tyramine in culture medium and honey bee larvae with a limit of quantitation of 3 ng/mL and a recovery rate of >97% using Liquid Chromatography-Mass Spectrometry/Mass Spectrometry and deuterium-labeled tyramine, demonstrating for the first time that a highly virulent M...

Mastitis causes significant economic losses to the dairy industry due to decreased milk production in infected cows. Identification of mastitis-causing pathogens, such as streptococci, is necessary for selecting an effective antibiotic for treating mastitis. Although bacterial cultivation is widely used for pathogen identification, it requires more than 24 hr to complete. Contrarily, Lateral flow assays are simple, rapid, and inexpensive testing procedures. In this study, the effectiveness of an immunochromatographic test kit for detecting streptococci in milk samples from cows with clinical mastitis was evaluated as an alternative to bacterial cultivation...

The study aimed to investigate the effect of Grid1, encoding the glutamate ionotropic receptor delta type subunit 1(GluD1), on puberty onset in female rats. Grid1 mRNA and protein expression was detected in the hypothalamus of female rats at prepuberty and puberty. Additionally, the expression of Grid1 was suppressed in primary hypothalamus cells and prepubertal rat. Finally, investigated the effect of Grid1 knockdown on puberty onset and reproductive performance. The levels of Grid1 mRNA in the hypothalamus, the fluorescence intensity in the arcuate nucleus and paraventricular nucleus of the prepubertal rats was significantly lower than pubertal...

This study investigated the diagnostic and surgical management of urachal abscessation involving the urinary bladder in three cattle aged >18 months. While the abdominal floor or paralumbar fossa are typically considered for accessing the urachus and bladder in calves and heifers, the distance is too great to perform the procedure under direct vision in adult cows. Therefore, a novel preinguinal approach was used for access in cows with urachal abscesses after 18 months. Access was successfully achieved in all the three cows through a preinguinal incision to the urachal abscess at the apex of the bladder...

In the present study, recombinase polymerase amplification (RPA) was combined with the colloidal gold lateral flow dipstick (LFD) method to establish a new, stable, and efficient assay for the detection of canine distemper virus (CDV). We designed a set of specific primers labeled with biotin and a specific probe labeled with dSpacer and C3 spacer, according to the conserved region in the N-terminal gene sequence of CDV. The reaction conditions and systems were then optimized, and the sensitivity and specificity were analyzed for potential clinical application...

A 1-year-old mixed-breed cat was referred for an approximately 2-cm mass centered on the upper right canine tooth. Computed tomography (CT) revealed the lesion extended to the nasal cavity and orbit, causing thinning and expansion of the adjacent cortical bone. Excisional biopsy confirmed the diagnosis of a feline inductive odontogenic tumor. Based on the findings of CT imaging, the primary alveolar bone lesion was removed with the tumor, while the adjacent bones, which had been expanded and thinned, were preserved by marginal resection including the surrounding periosteum-like membrane...

The components of milk from beef cows remain to be elucidated. This study examined the differences in the antimicrobial components of milk between dairy and beef cows. Quarter milk was collected from both Japanese Black (beef type) and Holstein (dairy type) cows to compare the concentrations of antimicrobial components. The concentration of lingual antimicrobial peptide (LAP) was higher, whereas that of the other antimicrobial components (lactoferrin, S100A7, and S100A8) was lower in beef cows than in dairy cows...

Spirometra infections in companion animals and wildlife in Japan have been diagnosed based on the morphology of the adult worms and eggs, and the etiological agent has been mainly ascribed to Spirometra erinaceieuropaei. However, recent studies have revealed that two other species, Spirometra mansoni and Spirometra asiana, coexist in Japan. Spirometra asiana is a new species recently discovered in Japan. Although morphological discrimination between these two species is difficult, molecular identification is useful...

In this study, we examined the morphological features of the placentas from 3 species of rorqual whales (Balaenopteridae), namely Bryde's (Balaenoptera brydei), sei (B. borealis), and common minke (B. acutorostrata) whales, and verified the secretion of 2 placental-specific peptide hormones, placental lactogen (PL) and chorionic gonadotropin (CG). The placentas were collected in the second phase of the Japanese Whale Research Program under a special permit in the North Pacific (JARPN Ⅱ) between 2009 and 2010...

Cranial cruciate ligament rupture (CCLR) is a common cause of stifle joint pain in dogs. This study assessed the short-term outcomes in the management of CCLR, with or without concurrent medial patellar luxation (MPL), in small-breed dogs, comparing surgical intervention using tibial plateau leveling osteotomy (TPLO) with non-surgical approaches. Dogs weighing less than 10 kg and suffering from CCLR were divided into two groups: surgical and non-surgical (nine stifles per group). Both groups followed the same rehabilitation protocol...

This study investigated age-related radiographic changes in the distal parts of the forelimbs by radiographic evaluation and identified the radiographic changes associated with diseases specific to foals. The hoof angle (HA), distal phalanx angle (P3A), distal phalanx palmer angle (P3PA), distal interphalangeal joint angle (DIPJA), and metacarpophalangeal joint angle (MPJA) on lateromedial radiographs of forelimbs were measured on the day after birth (Day 1); at 1, 2, 4, 6, and 8 weeks of age; and then at monthly intervals until 12 months of age...

In this study using computed tomography (CT), the volumes of the internal cranial cavities, such as the braincase, frontal sinus and tympanic cavity, and the ratio of the volume of each cavity to the skull volume in Japanese wolves were quantified, and CT images of the frontal sinus were observed. The results were then compared with those of other wolf subspecies, including Akita, a dog breed, to clarify the characteristics of the internal cranial cavities in Japanese wolves. The present study revealed that the Japanese wolf had a relatively larger braincase volume and a relatively smaller frontal sinus volume than the wolf ssp...

Here we report a case series of two dogs diagnosed as renal interstitial cell tumor (RICT) accompanied by elevated serum erythropoietin level and marked polycythemia. RICT is a rare tumor in dogs, originating from renal interstitial cells. While several renal tumors such as renal lymphoma, adenocarcinoma, carcinoma, sarcoma, fibrosarcoma and nephroblastoma may cause polycythemia, polycythemia caused by RICT has never been reported in dogs. The tumors in both dogs were solitary and lied within cortex or cortico-medullary junction...

Ezetimibe is a cholesterol absorption inhibitor that blocks the intestinal absorption of both biliary and dietary cholesterol, thereby lowering primarily low density lipoprotein-cholesterol (LDL-chol) in human studies. This study aimed to investigate the effects of ezetimibe on dyslipidemia control in nine dogs with hypercholesterolemia. Changes in total cholesterol (T-chol) and each lipoprotein fractions were evaluated at 0, 2, and 4 months following initiation of ezetimibe treatment. A significant decrease in T-chol was observed, and a mean T-chol concentration below 400 mg/dL was achieved at 2 and 4 months...

Sensorineural hearing loss (SNHL) induced by noise has increased in recent years due to personal headphone use and noisy urban environments. The study shows a novel model of gradually progressive SNHL induced by repeated exposure to moderate noise (8-kHz octave band noise, 90-dB sound pressure level) for 1 hr exposure per day in BALB/cCr mice. The results showed that the repeated exposure led to gradually progressive SNHL, which was dependent on the number of exposures, and resulted in permanent hearing loss after 5 exposures...

A mixed-breed, 8-year-old male dog developed neutropenia, thrombocytopenia, and hyperglobulinemia. Bone marrow hyperplasia and splenic plasmacytosis were cytologically observed. The dog had never been outside of Tokyo or Shizuoka Prefecture. Splenectomy was performed to confirm and remove the cause of splenic plasmacytosis. A histopathological diagnosis of splenic plasmacytoma was made; however, serum protein electrophoresis showed polyclonal gammopathy. Further screening was performed, and Ehrlichia canis infection was confirmed...

Pestiviruses are classified into two biotypes based on their cytopathogenicity. As the majority of pestivirus field isolates are noncytopathogenic, their titration requires alternative methods rather than direct observation of cytopathogenic effects, such as immunostaining using specific antibodies or interference with cytopathogenic strains. However, these methods require microscopic observation to assess virus growth, which is time- and labor-intensive, especially when handling several samples. In this study, we developed a novel luciferase-based pestivirus titration method using the superinfection exclusion phenomenon with recombinant reporter pestiviruses that possessed an 11-amino-acid subunit derived from NanoLuc luciferase (HiBiT)...

Fosfomycin (FOM) is an approved veterinary medicinal product for large animals in Japan, but Clinical breakpoint (CBP) for antimicrobial susceptibility test (AST) is not defined for animals. This study aimed at conducting a pharmacokinetics/pharmacodynamics (PK/PD) analysis to determine the PK/PD cutoff for the CBP in horses. Drug concentrations following single intravenous administration (IV) of 20 mg/kg body weight (BW) FOM in nine horses were measured using liquid chromatography/mass spectrometry. The data were modelled using a nonlinear mixed-effects model, followed by Monte Carlo simulations...

Chicken chaphamaparvovirus causes diarrheal symptoms and can be detected in fecal samples. This study reports the detection of chicken chapparvovirus 2 in debilitated chickens with hemorrhagic hepatitis at a broiler farm in Japan. After euthanasia and necropsy, liver hemorrhage was observed. Nuclear inclusion bodies in the hepatocytes were identified using histological analysis. High-throughput sequencing analysis using RNA from livers of three affected chickens revealed infection by chicken chapparvovirus 2 and chicken anemia virus...

After the native population of Oriental stork (Ciconia boyciana) in Japan disappeared, a reintroduction project was implemented in 2005. All released storks and most wild-fledged storks were individually identified using colored rings on their legs. The size of the reintroduced population reached 256 by the end of 2021. In this study, we investigated the causes of stork injury and death in wild populations to clarify important medical issues for successful reintroduction. During the survey, 153 of 412 (78 released and 334 fledged storks) storks were injured or died between 2005 and 2021...