The economic loss caused by mastitis in dairy cows is extremely large worldwide and remains an issue where improvement is needed. The focus of this study was on-site measurement technology. We evaluated the usefulness of resistive pulse sensing (RPS) particle measurement in comparison with standard measurement and the clinical findings of udder quarters in cows. We measured the particle count in milk samples collected from healthy udder quarters, calculated statistically normal values, and judged cases with significantly deviated values as abnormal. We found that abnormal values detected using RPS measurement corresponded to those using standard measurement. Furthermore, it was possible to identify which specific udder quarter was causing the abnormality, and this matched the abnormalities observed in clinical findings. RPS also enabled the detection of subclinical abnormalities in udder quarters showing no visible symptoms. RPS is a simple particle measurement method, and it cannot be used to diagnose disease directly; however, its use on-site can facilitate the early detection of abnormalities and help to maintain milk quality. Because the device used in RPS mainly measures electrical current, it can be manufactured at low cost, making RPS a promising tool for future point-of-care testing.
A 17-day-old Japanese Black calf was presented with bilateral corneoconjunctival dermoids causing corneal irritation, corneal opacity, and visual impairment. Preoperative ocular ultrasonography showed no abnormalities of the lens, vitreous body, or posterior segment. After excision of the extensive dermoid lesions, large corneal defects remained; therefore, conjunctival flap reconstruction was performed to support corneal healing. Histopathological examination confirmed the diagnosis of ocular dermoid. Postoperative ocular ultrasonography revealed no intraocular abnormalities, and visual function recovered within 1 month after surgery. This case suggests that perioperative ocular ultrasonography may help assess surgical candidacy and monitor postoperative complications. Conjunctival flap reconstruction may be effective for managing extensive corneoconjunctival dermoids in calves.
Non-ST segment elevation myocardial infarction (NSTEMI) is caused by partial occlusion of a coronary artery due to atherosclerotic plaque disruption and superimposed thrombus formation. Common electrocardiographic findings in NSTEMI include permanent ST segment depression, indicative of subendocardial myocardial infarction. In our earlier research, we simulated the ST segment elevation observed in human ischemic heart disease by inducing subepicardial burn injuries in the bullfrog heart ventricle. In the present study, we successfully replicated ST segment depression, similar to that observed in patients with subendocardial myocardial infarction, by inducing burn injuries on the subendocardial surface of the frog heart ventricle, as confirmed by histological examination. The currents of injury generated by the damaged endocardium were thought to be responsible for this electrocardiographic change.
We recently identified a domestic cat hepatitis B virus (DCHBV) outbreak at a cat shelter in Okinawa, Japan. Viral genome sequencing showed that this particular strain was highly conserved and distinct from previously reported Japanese strains, suggesting that a single strain had spread within the shelter. However, the origin of this strain remained unclear. DCHBV strains were also identified in two stray cats in central Okinawa. The outbreak strain shared 99.4-99.8% and 99.5-99.8% nucleotide identity with the strain from stray cat #1 and #2, respectively, indicating a close genetic relationship among all DCHBV strains identified in Okinawa. Our findings highlight the importance of screening stray cats for DCHBV before admission to shelters to help prevent outbreaks.
A 9-year-old neutered male Labrador Retriever presented with increased intraocular pressure in the left eye and underwent enucleation for a suspected intraocular tumor. Grossly, a white to greyish-white solid mass occupied the anterior segment and was partially contiguous with the lens. Histologically, the tumor exhibited biphasic proliferation of epithelial and mesenchymal components. The mesenchymal component showed osteoid formation, and transitional features were observed between the two components. Based on histological and immunohistochemical findings, the tumor was diagnosed as a carcinosarcoma composed of an iridociliary adenocarcinoma component and an osteosarcomatous component. This is the first report of carcinosarcoma in the canine eye, expanding the understanding of the morphological diversity and histogenetic characteristics of canine iridociliary tumors.
This study aimed to determine the incidence of emesis in dogs receiving a low dose of intravenous medetomidine. Anesthetic records of dogs that received ≤3 µg/kg medetomidine intravenously before anesthesia induction were retrospectively reviewed. Data included demographics, doses, and the presence of emesis, retching, sialorrhea, or lip licking. A total of 155 cases met the criteria. The administered dose of medetomidine was 3.0 (0.5-3.0) µg/kg (median [range]). Emesis occurred in 3 of 155 dogs (1.9%), while retching, sialorrhea, and lip licking occurred in two, two, and five dogs, respectively. The incidence of emesis observed in dogs receiving low-dose (≤3 µg/kg) intravenous medetomidine was lower than that reported in studies using higher doses.
This report describes fungal dermatitis in a breeding colony of diplodactylid geckos (Correlophus ciliatus and Rhacodactylus auriculatus). Following the introduction of one gecko, the introduced gecko and two with indirect contact died with severe skin lesions. Subsequently, four geckos developed diarrhea, melena, emaciation, and dermatitis and died. Histopathologically, all cases showed necrotizing dermatitis with filamentous fungi. Nannizziopsis arthrosporioides was isolated and identified from two geckos, and these two animals were definitively diagnosed with a fatal cutaneous fungal infection caused by N. arthrosporioides. This is the first report of such cases in diplodactylid geckos in Japan. From an epidemiological perspective, we inferred that an outbreak caused by this fungus had occurred in a colony.
Serotonin (5-HT) regulates gastrointestinal (GI) motility by activating various 5-HT receptor (5-HTR) subtypes. However, the expression and distribution of 5-HTR subtypes in the GI tract of Japanese Black cattle under both healthy and diseased conditions remain largely unknown. This study examined the expression of seven-transmembrane 5-HTR subtypes in healthy and fat necrosis (FN)-affected Japanese Black cattle. We found clear expression of 5-HT1BR, 5-HT2BR, 5-HT4R, and 5-HT7R mRNAs in the GI tract, in both young and adult groups. Expression of 5-HT4R and 5-HT7R was higher at most sites in adult cattle than in young cattle. The highest 5-HT4R expression was observed in the colon of adult cattle. Given the availability of antibodies and use of 5-HT4R agonists in therapy, we further examined the localization of 5-HT4R. We detected 5-HT4R mRNA and protein in neurons of the myenteric and submucosal plexuses. In FN-affected cattle, expression of 5-HT1BR, 5-HT2BR, and 5-HT7R mRNAs tended to decrease in the GI tract, while 5-HT4R mRNA remained unchanged, in comparison with healthy adult cattle. Our results show that 5-HT1BR, 5-HT2BR, 5-HT4R, and 5-HT7R mRNAs are obviously expressed in the GI tracts of Japanese Black cattle. Because 5-HT4R mRNA expression did not differ between healthy and FN-affected cattle, 5-HT4R agonists may offer therapeutic benefits for both groups, suggesting potential for clinical application in Japanese Black cattle.
Snakebite-induced local tissue damage remains a challenge in snakebite envenoming management because venom toxins rapidly disrupt vascular and extracellular matrix integrity at the bite site. This study evaluated the inhibitory effect of marimastat, an inhibitor of zinc-dependent metalloproteinases, against local tissue damage induced by Indonesian Trimeresurus insularis and Calloselasma rhodostoma venoms in a mouse skin model. The minimum hemorrhagic dose (MHD) of C. rhodostoma venom was determined in BALB/c mice and estimated to be 7.07 µg, while the MHD of T. insularis was adopted from a previous study. Mice received intradermal injections of venom at 2× MHD, either alone or pre-incubated with marimastat at venom:marimastat ratios of 1:1, 1:5, and 1:10 based on MHD equivalents. Macroscopic hemorrhage and histopathological changes, including erythrocyte extravasation, inflammatory cell infiltration, and collagen degradation, were assessed three hours after injection. Both venoms induced marked hemorrhagic lesions and tissue damage. Marimastat reduced venom-induced hemorrhage in both models, with near-complete inhibition in the T. insularis 1:10 group and complete inhibition in the C. rhodostoma 1:10 group. Marimastat also decreased erythrocyte extravasation, inflammatory infiltration, and collagen degradation, indicating preservation of microvascular and dermal matrix integrity. These findings support the central role of snake venom metalloproteinases in local viperid tissue damage and highlight marimastat as a promising adjunctive treatment for reducing venom-induced skin injury.
A 7-year-old intact male toy poodle presented with abdominal distension, polydipsia, and polyuria. Abdominal ultrasonography revealed bilateral adrenal atrophy, and adrenocorticotropic hormone (ACTH) stimulation testing showed persistently low cortisol concentrations with concurrent low endogenous ACTH, indicating central hypoadrenocorticism. To localize dysfunction within the hypothalamic-pituitary-adrenal axis, a corticotropin-releasing hormone (CRH) stimulation test was performed. Endogenous ACTH increased markedly after CRH administration, whereas cortisol remained undetectable, demonstrating preserved pituitary responsiveness and supporting a diagnosis of hypothalamic hypoadrenocorticism. Treatment of hypoadrenocorticism with prednisolone alone resulted in long-term clinical stabilization without electrolyte abnormalities for over one year. To our knowledge, this is the first canine report classifying suspected hypothalamic hypoadrenocorticism using CRH stimulation testing.
Reference intervals (RIs) are essential for interpreting laboratory results. We established hematological and serum biochemical RIs for apparently healthy Mongolian Bactrian camels and evaluated age/physiological class and seasonal effects. Samples were collected from yearlings, subadults, adult castrated males, and lactating adult females in spring and autumn. Following CLSI EP28-A3c and ASVCP guidelines, 95% RIs were estimated by parametric, nonparametric, or robust methods according to sample size and distribution. Age/physiological class influenced multiple analytes, while season explained greater variation in several erythroid indices, total protein, and glucose. Season-specific RIs are therefore provided for analytes with substantial seasonal effects. These locally derived RIs support clinical interpretation and herd health monitoring under Mongolian pastoral conditions.
Ectopic ossification is defined as bone formation at a site where no bone tissue typically exists and usually presents a trabecular bone structure. Rare cases of ectopic ossification in cardiac masses have been previously reported. In general, cardiac masses are diagnosed by echocardiography, computed tomography, and magnetic resonance imaging (MRI). MRI, in particular, has been used in studies to evaluate cardiometabolic function and tumors in various non-human primates (NHPs). Here, we report a 15-year-old male cynomolgus monkey with significant weight loss and arrhythmia observed during a routine checkup. This is the first report of a cynomolgus monkey in which a cardiac mass with bone metaplasia in the right ventricle was confirmed by echocardiography, radiography and MRI before death.
When applying embalmed cadavers and organ specimens to gross anatomy practice and surgical training, their qualitative properties serve as important functional indices of how closely they resemble the living state. Among these properties, color hue and stiffness change remarkably after fixation. In the present study, we evaluated the properties of rat organs, including the brain, lung, liver, and skeletal muscle, after fixation by immersion in a 10% formalin solution and a non-formalin fixative, ethylene glycol-methanol-phenol (EMP) mixture. The colorimetric L*a*b* values, which are indicators of the lightness and chromatic components, showed that, compared with formalin fixation, EMP fixation significantly increased lightness in the lungs and livers, suggesting decoloration as a result of hemolysis and hemochrome elution, whereas deposition of a reddish pigment was induced in the brains and skeletal muscles. The ΔE values, the total color difference from the unfixed state, were higher in the EMP- than in the formalin-fixed livers. The biomechanical parameters for stiffness indicated that the EMP-fixed brains were hardened similar to those fixed by formalin, while the other EMP-fixed organs were significantly hardened compared with their formalin-fixed counterparts. These findings suggest that EMP fixation exerts a beneficial effect by enhancing reddish coloration, especially in the skeletal muscles, and would be useful for reducing the total amount of highly toxic formalin used in gross anatomy practice.
Three Japanese Black calves died within a two-month period on a beef cattle farm. Necropsy consistently revealed liquefactive necrosis of the ventral brain (extending from the olfactory bulb to the midbrain) and thymic atrophy. Histopathologically, necrosuppurative encephalitis characterized by abundant fungal hyphae was observed in all three cases. Fungal lesions also involved the olfactory mucosa, olfactory nerves, and olfactory bulb. Fungi isolated from the cerebrum of all three calves were identified as Lichtheimia ramosa. These cases were diagnosed as rhinocerebral mucormycosis, originating in the olfactory mucosa and extending to the cerebrum. Although mucormycosis is typically sporadic, this report documents the first occurrence of consecutive cases of bovine rhinocerebral mucormycosis caused by L. ramosa.
Antimicrobial resistance is a global public health threat, and accurate antimicrobial susceptibility testing is crucial for guiding appropriate antimicrobial use. Although the disk diffusion method is widely used in livestock, standardized breakpoints for veterinary pathogens are lacking. Bovine respiratory disease, a major cause of economic loss in calves, is commonly associated with Pasteurella multocida and Mannheimia haemolytica. This study aimed to establish inhibition zone diameter cut-off values for disk diffusion and to create an antibiogram for these pathogens. The cut-off values were calculated based on minimum inhibitory concentration (MIC) reference values: the Clinical and Laboratory Standards Institute clinical breakpoints for penicillin and tetracycline; the European Committee on Antimicrobial Susceptibility Testing epidemiological cut-off values for kanamycin and tilmicosin (P. multocida); and MIC cut-off values calculated from this study for cefazolin, marbofloxacin, thiamphenicol, and tylosin. The cut-off values for penicillin and tetracycline provide useful guidance for clinical drug selection, whereas caution is required when interpreting the results for the other agents evaluated because their cut-off values were based on epidemiological cut-offs rather than clinical breakpoints. Re-evaluation of previously reported cut-off values for kanamycin, cefazolin, and tetracycline using a larger number of isolates provided more robust thresholds that were less susceptible to strain-specific variation. The antibiogram revealed low susceptibility rates for some agents. Because antimicrobial use is associated with the development of resistance, these findings indicate the need for prudent antimicrobial stewardship and continued surveillance of resistance in livestock pathogens.
A 5-year-old cat presented with exophthalmos and neurological signs. Aspergillus udagawae was identified by histopathological examination and polymerase chain reaction (PCR) analysis of an orbital mass. Although magnetic resonance imaging suggested intracranial infection, cerebrospinal fluid (CSF) analysis and fungal culture were not clear. Serial CSF PCR detected Aspergillus sp., leading to diagnosis of central nervous system (CNS) infection and monitoring of treatment response. Following surgical debulking and administration of antifungal agents including voriconazole, the clinical signs resolved and CSF PCR reverted to negative. This case suggests that CSF PCR is a sensitive adjunctive tool for diagnosing and monitoring CNS aspergillosis in cats when conventional methods are inconclusive.
Heart rate variability (HRV) analysis is widely used to evaluate autonomic nervous system activity. Although a fixed 16th-order autoregressive (AR) model is commonly used for human short-term frequency-domain HRV analysis, its applicability to dogs has not been validated. This study evaluated the suitability of the fixed 16th-order AR model for canine HRV analysis by comparing HRV indices obtained using AR(16) with those derived from Akaike's Information Criterion (AIC)- and Bayesian Information Criterion (BIC)-selected AR models and the conventional fast Fourier transform (FFT) method. Twenty-three clinically healthy dogs underwent continuous heart rate monitoring for approximately 3 days using a wearable device. One stationary 5-min R-R interval segment was selected from each recording, and frequency-domain HRV indices were calculated using AR(16), AIC-selected AR models, BIC-selected AR models, and FFT. Agreement among methods was evaluated using intraclass correlation coefficients and Bland-Altman analysis. HRV indices obtained using AR(16) showed excellent agreement with AIC-selected model orders and good agreement with FFT, whereas agreement with BIC-selected model orders was lower, particularly for low-frequency-related indices. These findings support the applicability of the conventional fixed 16th-order AR model for canine frequency-domain HRV analysis and provide methodological validation for its use in future veterinary HRV research.
As the frequency and significance of bone marrow (BM) infiltration in enzootic bovine leukosis (EBL) remain unclear, this study evaluated BM involvement and its relationship with peripheral blood (PB) findings in 11 cattle with EBL using PB evaluation, and BM aspiration cytology. BM infiltration was identified in 5 of 11 (45%) EBL cases based on BM smears. All EBL cases showed circulating atypical lymphocytes, although BM infiltration was not consistently present. Two cases with extreme PB lymphocytosis showed BM infiltration. Cytopenia was variably observed and was most severe in cases with extensive BM involvement. This study provides combined assessment of PB and BM changes in EBL cattle and suggests that such evaluation enables a more comprehensive characterization of hematological alterations.
A 1-day-old Holstein calf presented with central corneal opacity and thickening, and a polypoid lesion in the medial canthus of the left eye, leading to vision loss and enucleation. Grossly, a mass extended from beneath the cornea to the medial intraocular region. Histologically, the mass was composed of proliferative foci of diverse mesenchymal elements, including mature cartilage and adipose tissue, immature cartilage and bone, and proliferating spindle-shaped cells in a myxoid stroma. Anterior segment abnormalities, including iris hypoplasia, iridocorneal adhesion, angle malformation, and lens anomalies, were also observed. The animal was diagnosed with an ocular choristoma with heterogeneous mesenchymal differentiation and anterior segment dysgenesis (ASD). To the best of our knowledge, this is the first report of choristoma with ASD in cattle.
An 11-year-old toy poodle presented with abnormal gait. Magnetic resonance imaging revealed a demarcated intradural extramedullary mass at the dorsal medulla oblongata, which was surgically removed. Histopathologically, a well-demarcated tumor was composed of small nests of meningothelial neoplastic cells separated by abundant fibrovascular tissue. The nuclei of neoplastic cells were often eccentric due to eosinophilic cytoplasmic inclusion bodies. Immunohistochemically, the neoplastic cells were positive for E-cadherin and vimentin, and endothelial cells were positive for CD31, von Willebrand factor, and vimentin. The cytoplasmic inclusion bodies of the neoplastic cells were E-cadherin-positive and, by electron microscopy, composed of folded membrane-like structures. The tumor was diagnosed as an angiomatous meningioma with cytoplasmic inclusion bodies, which were likely cell membranes containing E-cadherin.
