Breed-related expression patterns of Ki67, γH2AX,and p21 during ageing in the canine liver

Veterinary Research Communications - Cellular senescence is a molecular hallmark of ageing that is associated with multiple pathologies, and DNA damage marker γH2AX, together with cell cycle...     

Distribution of substance P and calcitonin gene-related peptide in the spinal cord of Cavalier King Charles Spaniels affected by symptomatic syringomyelia

The causes of clinical signs associated with syringomyelia in the Cavalier King Charles Spaniel (CKCS) are incompletely understood. In this study we compared expression of two pain-related neuropeptides: substance P (SP) and calcitonin gene related peptide (CGRP), in the spinal cord dorsal horn of normal dogs with that in CKCS with and without clinical signs of syringomyelia. There was a decrease in expression of both peptides in CKCS with 'symptomatic' syringomyelia that was also associated with significant asymmetry in SP-I and similar, though non-significant, asymmetry in CGRP-I compared with other groups. The asymmetric distribution of these pain-related peptides may be a consequence of syrinx-associated damage to grey matter but may also play a role in generation of pain.     

Breed, age and gender distribution of dogs with chronic hepatitis in the United Kingdom

Standardised histological criteria are now available for the diagnosis of canine chronic hepatitis (CH). CH is common in dogs, but no studies have reported breed, age and gender distributions in the United Kingdom (UK). The objective of this study was to determine which breeds had an increased risk for developing CH in the UK and to report the age and gender distribution for those breeds. The databases of six veterinary histopathology laboratories were searched for cases with a histological diagnosis of CH according to standardised criteria. The breed, age and gender of dogs was recorded and compared to a control population to calculate the odds ratio and 95% confidence intervals for developing CH. A total of 551 cases of CH were identified, consisting of 61 breeds. Nineteen breeds were represented by five or more cases. Breeds with an increased risk for developing CH included the American cocker spaniel, Cairn terrier, Dalmatian, Dobermann pinscher, English cocker spaniel, English springer spaniel, Great Dane, Labrador retriever and Samoyed. The median age at diagnosis for all breeds with CH was 8 years (range 7 months to 16 years). Dalmatians, Dobermann pinschers and English springer spaniels with CH were significantly younger than Cairn terriers, English cocker spaniels and Labrador retrievers with CH. Females were over-represented when all cases were examined together. In conclusion, several breeds in the UK have an increased risk of CH, some of which have not been previously reported.     

Chronic hepatitis in the English springer spaniel: clinical presentation, histological description and outcome

Medical records and liver histology of 68 English springer spaniels (ESS) with a histological diagnosis of CH were reviewed retrospectively. PCR was performed on liver tissue for canine adenovirus-1 (CAV-1), canine parvovirus, canine herpesvirus and pathogenic Leptospira species. Follow-up information was obtained to calculate survival times. Median age at presentation was three years seven months (range, seven months to eight years five months) and there were 48 female and 20 male dogs. Clinical signs were non-specific and five dogs were asymptomatic. All dogs had an increase in serum activity of one or more hepatobiliary enzymes. Histopathology demonstrated hepatocyte necrosis and apoptosis with varying amounts of fibrosis. A predominantly lymphoplasmacytic infiltrate throughout the hepatic parenchyma was found in all 68 dogs, but 45 of these dogs also had a neutrophilic component to the inflammatory infiltrate. There was no significant copper accumulation and no aetiological agent was identified by PCR. The median survival time was 189 days (range, 1 to 1211 days), 38 dogs died within three months and 12 dogs survived more than a year following diagnosis.     

The clinical presentation and histopathologic-immunohistochemical classification of histiocytic sarcomas in the Flat Coated Retriever

The Flat Coated Retriever is a breed at risk of development of histiocytic sarcoma (HS), but in contrast to the disseminated form of disease recognized in the Bernese Mountain Dog, most reports of HS in Flat Coated Retrievers describe a localized lesion affecting the musculature or fascia of limbs. The purpose of this study was to review data and material received though an ongoing Flat Coated Retriever tumor survey to better define the presentation of HS in the breed and to determine the utility of subclassification of tumors arising at different sites by histology and immunohistologic phenotyping. Data on 180 dogs bearing HS-like tumors were available for review, which showed that although the majority (101 lesions, 57%) were primary limb lesions, 47 dogs (26%) had visceral, mainly splenic lesions with no peripheral primary tumor. A detailed histologic and immunohistologic review of 20 limb tumors and 20 splenic tumors showed that 2 distinct phenotypic subtypes could be identified: a histiocytic subtype, most prevalent in the splenic tumors, and a histiocytic-spindle-pleomorphic subtype, mainly seen in the limb tumors. Despite their variable morphology, all tumors expressed major histocompatibility complex class II and the leukocyte antigen CD18, but only those tumors in the spleen consistently expressed CD11d. The majority of tumors also contained a mild to moderate infiltrate of T lymphocytes.     

Choroid plexus carcinoma cells in the cerebrospinal fluid of a Staffordshire Bull Terrier

An 11-year-old female intact Staffordshire Bull Terrier was referred to the Queen's Veterinary School Hospital at the University of Cambridge with sudden onset of episodic behavioral changes, a mammary mass, and papilledema in the right eye. On physical examination the dog appeared depressed and had a head tilt to the right with anisocoria. Using magnetic resonance imaging, a broad-based lesion that obliterated the fourth ventricle was detected in the right brainstem. There was no evidence of pulmonary metastasis. Cerebrospinal fluid (CSF) was then obtained; fluid analysis showed an increased cell count (165 cells/μL, reference interval 0-7 cells/μL) and total protein (0.30 g/L, reference value <0.25 g/L). Cytologic evaluation revealed a population of atypical epithelial cells arranged in cohesive rafts and characterized by moderate to occasionally marked anisocytosis and anisokaryosis. The appearance was highly suspicious of a malignant epithelial neoplasm. The dog was euthanized and on postmortem examination an asymmetrical nonencapsulated cerebellar mass was found within the choroid plexus of the fourth ventricle with local extension into the cerebellopontine angle. Histologic sections of the cerebellar mass contained arborizing papillary structures covered by a single layer of atypical epithelial cells that showed local infiltration into the adjacent neuropil. The diagnosis was choroid plexus carcinoma. The atypical epithelial cells were negative for pancytokeratin and strongly positive for vimentin. The finding of clusters of choroid plexus epithelial cells in the CSF demonstrates the value of utilizing a relatively noninvasive diagnostic technique for diagnosis of choroid plexus tumors.     

Intentional marginal excision of canine limb soft tissue sarcomas followed by radiotherapy

Objectives: To evaluate the outcome in a group of dogs treated with postoperative radiotherapy following intentional marginal excision of soft tissue sarcomas from their limbs and to assess parameters for prognostic significance. Method: Patients that had had intentional marginal excision of limb soft tissue sarcomas followed by radiotherapy were selected. A coarse fractionated protocol of four once weekly 8 to 9 Gy by 4 MV x-rays was used. The time to local recurrence was determined. Tumour grade, size, site, number of surgeries, surgeon and time from last surgery to radiotherapy were evaluated as potential prognostic indicators. Results: Fifty-six cases were included. Minor surgical complications occurred in four patients (7%). Tumour recurred locally in 10 dogs (18%). Fourteen dogs died from tumour-related causes (25%). From Cox proportional hazard analysis time from surgery to radiotherapy was the only predictor of tumour recurrence (P=0·039); hazard ratio 8·63. Delaying radiotherapy beyond 4 weeks was associated with improved outcomes. Three dogs developed serious but non-life-threatening local complications; wound dehiscence, self-trauma and osteonecrosis of underlying bone. Clinical Significance: Intentional marginal excision followed by hypofractionated radiotherapy is a viable option for canine limb soft tissue sarcomas, providing good long-term clinical outcomes and low morbidity.     

Studies on the evolution, pathology, and immunity of commercial fattening rabbits affected with epizootic outbreaks of diarrhoeas in Mexico: a case report

Epizootic outbreaks of diarrhoeas have emerged and disseminated in different rabbit farms in Mexico causing great economical losses, during the past years. Seven, 5-weeks-old New Zealand White (NZW) rabbits chosen at random from 35 ill animals that were remitted for postmortem, histopathology, and ultrastructural examinations were studied. Bacteriological and parasitological studies were carried out in three additional ill rabbits of same age. In a field trail 45, 5-weeks-old apparently healthy NZW rabbits were observed daily for sanitary status for a 5-week period. Some of the rabbits did not response to the preventive drug treatment and were therefore, used to study the development of the disease. Clinical signs, gross lesions, and mortality throughout the fattening period were recorded. Eight, 8-weeks-old NZW rabbits who survived an outbreak were assessed for gamma-globulins in serum of the total protein fraction during a 3-week period. Gamma-globulins were also measured in eight free-disease healthy rabbits of same breed and age. Lesions of the small intestine consisted of mucoid enteropathy, lymphocytic plasmocytic enteritis with atrophy and fusion of villi, and hyperplasia of globet cells. Serosal edema was present. Ultrastructural examinations of jejunum and ileum from 3/7 diseased rabbits, revealed enterocytes in apoptosis, mixed with degenerative and/or necrotic changes together with infiltration of lymphocytes, macrophages, neutrophils, and loss of microvillus. There were electron dense structures suggestive of virus particles inside the nuclei and cytoplasm of some enterocytes. There was lymphoid spleen atrophy and proliferation of reticuloendothelial cells in 7/7 rabbits. Interstitial pneumonia in 4/7 rabbits was found. Encephalitozoon cuniculi was detected in the brain of 1/7 rabbits. Escherichia coli were detected in 3/3 cases and Eimeria spp. in 2/3 cases. Mortality rate in the field study was 51.1% and the spread of the disease occur in 9/9 cages. The proportion of gamma-globulins in rabbits who survive an outbreak was much lower (P=0.0001) than free-disease healthy rabbits (8.1+/-1.0 and 14.0+/-1.0, respectively). The disease was multifactorial and consisted of sub-acute mucoid enteropathy probably induced by viral infection and aggravated by the proliferation of opportunistic pathogens common to rabbits. This may explain the severe degenerative and necrotic changes observed in the small intestine of diarrhoeic rabbits.