Differential expression of Toll-like receptors and inflammatory cytokines in ovine interdigital dermatitis and footrot.

Footrot is a common inflammatory bacterial disease affecting the health and welfare of sheep worldwide. The pathogenesis of footrot is complex and multifactorial. The primary causal pathogen is the anaerobic bacterium Dichelobacter nodosus, with Fusobacterium necrophorum also shown to play a key role in disease. Since immune-mediated pathology is implicated, the aim of this research was to investigate the role of the host response in interdigital dermatitis (ID) and footrot. We compared the expression of Toll-like receptors (TLRs) and pro-inflammatory cytokines and the histological appearance of clinically normal in comparison to ID and footrot affected tissues. Severe ID and footrot were characterised by significantly increased transcript levels of pro-inflammatory cytokines TNFα and IL1β and the pattern recognition receptors TLR2 and TLR4 in the interdigital skin. This was reflected in the histopathological appearance, with ID and footrot presenting progressive chronic-active pododermatitis with a mixed lymphocytic and neutrophilic infiltration, gradually increasing from a mild form in clinically normal feet, to moderate in ID and to a focally severe form with frequent areas of purulence in footrot. Stimulation with F. necrophorum and/or D. nodosus extracts demonstrated that dermal fibroblasts, the resident cell type of the dermis, also contribute to the inflammatory response to footrot bacteria by increased expression of TNFα, IL1β and TLR2. Overall, ID and footrot lead to a local inflammatory response given that expression levels of TLRs and IL1β were dependent on the disease state of the foot not the animal.This is the final version published by Elsevier in Veterinary Immunology and Immunopathology under a CC BY license. It was originally published here: http://www.sciencedirect.com/science/article/pii/S0165242714001706

Pathological findings in the pituitary glands of 201 dogs and cats

With the exception of classic functional adenomas in dogs and horses, pituitary lesions are infrequently described in the veterinary literature. Approximately 10% of pituitary glands from asymptomatic humans contain abnormalities but the equivalent proportion in small animals is unknown. Pituitary glands from 136 dogs and 65 cats collected during routine necropsies were examined to determine the prevalence of pituitary lesions and their histopathological diagnosis. Sections were stained with hematoxylin and eosin (HE), periodic acid-Schiff (PAS), Gordon and Sweet's reticulin and immunohistochemistry (against ACTH, GH, MSH-α and prolactin) stains for lesion characterisation.Pituitary abnormalities were identified in 36/136 (26.4%) dogs and 10/65 (15.3%) cats. Cystic changes were the most common lesion in dogs and cats, occurring in 18 (13.2%) dogs and 8 (12.3%) cats. Pituitary neoplasia was detected in 14.1% (12/85) of middle/old aged dogs; 1 (1.5%) cat had pituitary nodular hyperplasia. PAS enabled staining of secretory granules in ACTHimmunoreactive adenomas and reticulin stain helped differentiate them from hyperplastic nodules: adenomas showed PAS positive intracytoplasmic granules and loss of the normal reticulin network. One dog had a pituitary carcinoma with infiltration into the thalamus. Other pituitary abnormalities included: secondary metastases (2 dogs), hypophysitis (4 dogs, 1 cat). In the majority of cases the lesion appeared to be subclinical and could be considered incidental; of those cases with pituitary lesions, clinical manifestations were apparent in 4 dogs (2.9%) and no cats antemortem. Pituitary abnormalities are common in dogs and cats and their wider clinical relevance requires further investigation

Standardisation of canine meningioma grading: Inter‐observer agreement and recommendations for reproducible histopathologic criteria

The human grading system is currently applied to canine meningioma, although it has not been validated in dogs. The present study focused on standardising the human grading system applied to canine meningioma. Four veterinary neuropathologists graded 186 canine meningiomas as follows: Grade I tumour, with 50% of the tumour; (6) Report necrosis, small cells, hypercellularity and macronucleoli, even when focal; (7) Report anaplasia if multifocal

Discovery of os cordis in the cardiac skeleton of chimpanzees (Pan troglodytes)

© 2020, The Author(s). Cardiovascular diseases, especially idiopathic myocardial fibrosis, is one of the most significant causes of morbidity and mortality in captive great apes. This study compared the structure and morphology of 16 hearts from chimpanzees (Pan troglodytes) which were either healthy or affected by myocardial fibrosis using X-ray microtomography. In four hearts, a single, hyperdense structure was detected within the right fibrous trigone of the cardiac skeleton. High resolution scans and histopathology revealed trabecular bones in two cases, hyaline cartilage in another case and a focus of mineralised fibro-cartilaginous metaplasia with endochondral ossification in the last case. Four other animals presented with multiple foci of ectopic calcification within the walls of the great vessels. All hearts affected by marked myocardial fibrosis presented with bone or cartilage formation, and increased collagen levels in tissues adjacent to the bone/cartilage, while unaffected hearts did not present with os cordis or cartilago cordis. The presence of an os cordis has been described in some ruminants, camelids, and otters, but never in great apes. This novel research indicates that an os cordis and cartilago cordis is present in some chimpanzees, particularly those affected by myocardial fibrosis, and could influence the risk of cardiac arrhythmias and sudden death

Neuroaxonal dystrophy in a flock of pied imperial pigeons (Ducula bicolor)

Five juvenile pied imperial pigeons (Ducula bicolor) presented with neurological signs including torticollis, ataxia and poor flying ability. All were humanely destroyed and submitted for post-mortem examination. Microscopically, the most significant findings were in the brain and spinal cord. Spheroid formation was evident within the medulla, pons, diencephalon, cortical grey and subcortical white matter, spinal cord white and grey matter and the granular and molecular cell layers of the cerebellum. There was no evidence of associated inflammation. Immunohistochemistry revealed positive labelling within the spheroids for S100 axons and phosphorylated neurofilaments including SMI31, neurofilament cocktail and microtubule-associated protein 2. Transmission electron microscopy confirmed the light microscopical findings of frequent axonal spheroids. These results are consistent with neuroaxonal dystrophy, which has not been described previously in pigeons. This highlights the importance of considering neuroaxonal dystrophy in juvenile birds with neurological signs. A genetic basis is suspected in this group

Discovery Of A Bone In Chimpanzee Hearts

The os cordis (heart bone) is a rare bone found only in a few animals in the world. We discovered an os cordis in some chimpanzees. The os cordis was found in males and females, and in young and old animals. It was not present in chimps with healthy hearts, only in those with severe heart disease. We also discovered that a tissue called cartilage was present around the bone. The presence of cartilage gives us clues about how and why these rare bones develop

Trace metal accumulation through the environment and wildlife at two derelict lead mines in Wales

Trace metal pollution is globally widespread, largely resulting from human activities. Due to the persistence and high toxicity of trace metals, these pollutants can have serious effects across ecosystems. However, few studies have directly assessed the presence and impact of trace metal pollution across ecosystems, specifically across multiple environmental sources and animal taxa. This study was designed to assess the environmental health impacts of trace metal pollution by assessing its extent and possible transfer into wildlife in the areas surrounding two abandoned metalliferous mine complexes in Wales in the UK. Water, sediment, and soil at the mine sites and in areas downstream had notably elevated concentrations of Pb, Zn, and, to a lesser extent, Cd and Cu, when compared to nearby control sites. These high trace metal concentrations were mirrored in the body burdens of aquatic invertebrates collected in the contaminated streams both at, and downstream of, the mines. Wood mice collected in contaminated areas appeared to be able to regulate their Zn and Cu tissue concentrations, but, when compared to wood mice from a nearby control site, they had significantly elevated concentrations of Cd and, particularly, Pb, detected in their kidney, liver, and bone samples. The Pb concentrations found in these tissues correlated strongly with local soil concentrations (kidney: ρ = 0.690; liver: ρ = 0.668, bone: ρ = 0.649), and were potentially indicative of Pb toxicity in between 10 % and 82 % of the rodents sampled at the mine sites and in areas downstream. The high trace metal concentrations found in the environment and in common prey species (invertebrates and rodents) indicates that trace metal pollution can have far-reaching, ecosystem-wide health impacts long after the polluting activity has ceased, and far beyond the originating site of the pollution

Hereditary nephropathy in an English Cocker Spaniel

A thirteen-month-old male neutered orange roan English Cocker Spaniel dog was euthanized due to a prolonged history of lethargy, weight loss, severe azotemia and marked proteinuria, which was suggestive of chronic renal failure. At necropsy, both kidneys were pale tan and presented with a diffusely rough and granular appearing surface. Histologically, both kidneys showed severe, generalized, segmental to global, chronic membranoproliferative glomerulonephritis with glomerulosclerosis and proteinuria. DNA was extracted from hair follicles collected at necropsy, and a PCR amplifying exon 3 of gene COL4A4 was performed. The PCR showed that this dog had a homozygous mutation at the position 115 of the gene COL4A4, indicating that this dog suffered from hereditary nephropathy