Abstract. A total of 90 tumors from 85 domestic hamsters (70 Djungarian hamsters and 15 Syrian hamsters) were examined by histology. In the Djungarian hamsters, 64 neoplastic and 11 non-neoplastic lesions were identified, whereas 14 Syrian hamsters showed neoplastic disease, and one showed nonneoplastic disease. The Djungarian hamsters showed a high prevalence of neoplastic disease, similarly to laboratory Djungarian hamsters. In the Djungarian hamsters, almost all tumors were integumental, whereas hematopoietic tumors were the most common type in the Syrian hamsters. The most common integumental tumors in the Djungarian hamsters were mammary tumors, atypical fibromas and papillomas, and a spectrum of integumental tumors that have not been reported in laboratory Djungarian hamsters were identified. Most mammary tumors occurred in the females, whereas all atypical fibromas were observed in the males. In the Syrian hamsters, plasmacytomas and lymphomas were the most common tumors. The small number of Syrian hamsters in this study may reflect the low prevalence of spontaneous tumors seen in laboratory Syrian hamsters. The mean age of the affected hamsters was 19.8 months, which is relatively advanced. To our knowledge, this is the first comprehensive study of tumors in domestic hamsters.

The African pygmy hedgehog (Atelerix albiventris) is becoming a popular pet in Japan. The aim of this study was to determine the incidence of various diseases in African pygmy hedgehogs. We histologically investigated 105 samples from 100 privately-owned pet African pygmy hedgehogs that were submitted to two laboratories (North Lab and Patho Labo) between 2012 and 2017. Tissues submitted for this study were taken from female reproductive organs (33 cases; 31.43%), skin (20 cases; 19.05%), and the oral mucosa (19 cases; 18.1%). The most common histological diagnoses included endometrial stromal nodules identified as benign uterine neoplasia (14 cases; 13.33%); endometrial polyps identified as non-neoplastic polyps (7 cases; 6.67%), gingival hyperplasia and chronic suppurative inflammation in the oral mucosa (11 cases; 10.48%), fibrosarcomas in the skin (8 cases; 7.62%), and mammary tumors (8 cases; 7.62%). In this study, lymphoma and oral squamous cell carcinoma were less common than in the previous reports. The present study revealed the disease prevalence in captive African pygmy hedghogs that were histopathologically examined.

Background Aural cholesteatomas, also called tympanokeratomas, are destructive and expansile growths of keratinizing epithelium that develop in the middle ear. They have been reported sporadically in dogs, and surgery is usually the recommended treatment. Objectives To describe the common clinical, radiological and histological findings of cholesteatoma; to report on the outcome of conservative management. Animals Eleven dogs (13 ears) with cholesteatomas. Methods and materials Medical records were reviewed for dogs diagnosed with cholesteatoma between 2012 and 2018. All dogs had computed tomography (CT) and/or magnetic resonance imaging (MRI) followed by trans‐canal endoscopic procedure (TEP) for removal and biopsy of middle ear lesions. Dogs were then treated with in‐clinic flushing initially weekly tapered to monthly, as well as at‐home ear cleaning and application of topical otic steroid medication, initially daily then tapered to once or twice weekly. Results Nine dogs had a history of chronic otitis externa; head tilt or facial paralysis was present in seven and four cases, respectively. Otic examination identified a protruding nodule in seven ears. CT demonstrated soft tissue‐like material in 12 bullae and expansion in seven bullae. MRI revealed minimally contrast‐enhancing bulla contents in 12 ears. Post‐TEP and with maintenance medical treatment, nine ears had no further signs of middle ear disease during a mean follow‐up of 27.9 months. Conclusions and clinical importance The results suggest that otitis externa may not necessarily precede cholesteatoma in all dogs. MRI appears to be more sensitive than CT for identifying cholesteatomas. Conservative treatment of cholesteatomas could be useful before or as an alternative to surgery.

ABSTRACT. As ferrets can suffer from a wide variety of cardiac disorders, indicators for detecting cardiac abnormalities on plain chest radiography are necessary. A total of 64 ferrets without heart disease underwent radiography in the right lateral (RL) and ventrodorsal positions (VD), and the lengths of the RL-sixth dorsal vertebra (6th DV), RL-and VD-long axis (LA) and RL-and VD-short axis (SA), RLand VD-vertebral heart size, VD-length of the eighth costa (LEC) and VD-thoracic width at the eighth thoracic vertebra (8th TV) were measured to establish standard values of normal cardiac appearance. We evaluated statistical differences between genders and ferrets weighing < 1 kg and ≥ 1 kg for a total of 38 items. As a result, significant differences (P<0.05) were observed in all items, including some differences that have been reported previously. In particular, the present study established highly accurate standard values for weight differences. Standard values calculated based on the 6th DV and a relational expression obtained by the regression coefficient of the ratio of VD-SA to VD-8th TV, VD-8th TV=2.887 + (0.769 × VD-SA), were considered useful for evaluating normal cardiac morphology in ferrets.

An entire, female, mixed-breed cat of unknown age was presented with a 6-week history of lethargy, anorexia and vomiting. There was an increase in the number of white blood cells in the blood, including neutrophils and eosinophils; moderate anaemia; ascites; and possible mesenteric peritonitis. Exploratory laparotomy revealed firm, multifocal small nodules in the mesentery. As the nodules were surgically unresectable, they were biopsied. Histologically, the nodules were composed of thin trabeculae of dense collagen fibres mixed with plump fibroblasts and numerous eosinophils, consistent with feline gastrointestinal eosinophilic sclerosing fibroplasia. Bacteria were not detected on histological examination of the nodules and cytology of the ascites. Remission of disease occurred following treatment with prednisolone and ciclosporin A for 22 days and antibiotics for 40 days. After remission, ciclosporin A was administered for 236 days and then discontinued. Eosinophilia also resolved after treatment with ciclosporin A. The cat is still alive and in good condition on day 689. This report describes what may be an atypical case of feline gastrointestinal eosinophilic sclerosing fibroplasia, lacking involvement of the gastrointestinal tract, and was apparently cured by treatment that involved ciclosporin A.

It remains unclear whether epithelial cell-derived cytokines, including interleukin (IL)-25, IL-33 and thymic stromal lymphopoietin (TSLP), contribute to development of canine chronic enteropathy (CE), which includes antibiotic-responsive enteropathy (ARE), food-responsive enteropathy (FRE) and inflammatory bowel disease (IBD). In the present study, we examined mRNA expression of il-25, il-33 and tslp in the duodenal and colonic mucosae of dogs with ARE, FRE and IBD. Real-time PCR analysis revealed that mRNA expression of il-33 was significantly lower in the duodenum in dogs with FRE than in healthy dogs. The results suggest that epithelial cell-derived cytokines may not be an inducer of Th2-type immunity in the gut of dogs with CE, and decreased expression of IL-33 may be involved in induction of FRE. Further studies are required to clarify roles of epithelial cell-derived cytokines, especially IL-33, in the pathogenesis of canine CE.

BackgroundMucosal imbalance of interleukin (IL)‐1β and IL‐1 receptor antagonist (Ra) has been reported in the duodenal mucosa of dogs with inflammatory bowel disease (IBD). However, the imbalance in the colonic mucosa and its role in duodenitis and colitis in IBD of dogs remain unclear.ObjectivesTo measure the expression of IL‐1β and IL‐1Ra proteins in the colonic mucosa of dogs with IBD, and to determine the effect of IL‐1β on expression of occludin (ocln) mRNA, a tight junction component, in the duodenal and colonic mucosa of dogs with IBD.AnimalsTwelve dogs with IBD and 6 healthy dogs.MethodsIL‐1β and IL‐1 Ra proteins in the colonic mucosa were quantified by ELISA in 7 of the 12 dogs with IBD. Expression of ocln mRNA in the duodenal and colonic mucosa was examined in the 12 dogs by real‐time PCR.ResultsThe ratio of IL‐1β to IL‐1Ra in the colonic mucosa was significantly higher in dogs with IBD than in healthy dogs. The ex vivo experiment determined that IL‐1β suppressed expression of ocln mRNA in the colonic mucosa, but not in the duodenal mucosa, of healthy dogs. Expression of ocln mRNA in the colonic mucosa, but not in the duodenal mucosa, was significantly lower in dogs with IBD than in healthy dogs.Conclusions and Clinical ImportanceA relative increase in IL‐1β may attenuate ocln expression, leading to intestinal barrier dysfunction and promotion of intestinal inflammation in the colonic mucosa, but not in the duodenal mucosa, of dogs with IBD.

A 10-year-old castrated male miniature dachshund was presented with an abdominal mass. The dog had a history of splenectomy. Triple-phase helical computed tomography was utilized, revealing a hepatic mass and multiple intra-abdominal solid masses. In triple-phase helical computed tomography the images, hepatic mass and two of four intra-abdominal masses were heterogenous in all phases. Therefore, we diagnosed a malignant hepatic tumor and presumed intra-abdominal metastases. The masses were surgically removed and were histologically composed of normal spleen tissues, findings which were consistent with ectopic spleen.