Immunophenotypic evaluation of working Labrador Retrievers and German Shepherd dogs living in the same environment

Digital Lesions in Dogs: A Statistical Breed Analysis of 2912 Cases

Breed predispositions to canine digital neoplasms are well known. However, there is currently no statistical analysis identifying the least affected breeds. To this end, 2912 canine amputated digits submitted from 2014–2019 to the Laboklin GmbH & Co. KG for routine diagnostics were statistically analyzed. The study population consisted of 155 different breeds (most common: 634 Mongrels, 411 Schnauzers, 197 Labrador Retrievers, 93 Golden Retrievers). Non-neoplastic processes were present in 1246 (43%), tumor-like lesions in 138 (5%), and neoplasms in 1528 cases (52%). Benign tumors (n = 335) were characterized by 217 subungual keratoacanthomas, 36 histiocytomas, 35 plasmacytomas, 16 papillomas, 12 melanocytomas, 9 sebaceous gland tumors, 6 lipomas, and 4 bone tumors. Malignant neoplasms (n = 1193) included 758 squamous cell carcinomas (SCC), 196 malignant melanomas (MM), 76 soft tissue sarcomas, 52 mast cell tumors, 37 non-specified sarcomas, 29 anaplastic neoplasms, 24 carcinomas, 20 bone tumors, and 1 histiocytic sarcoma. Predisposed breeds for SCC included the Schnauzer (log OR = 2.61), Briard (log OR = 1.78), Rottweiler (log OR = 1.54), Poodle (log OR = 1.40), and Dachshund (log OR = 1.30). Jack Russell Terriers (log OR = −2.95) were significantly less affected by SCC than Mongrels. Acral MM were significantly more frequent in Rottweilers (log OR = 1.88) and Labrador Retrievers (log OR = 1.09). In contrast, Dachshunds (log OR = −2.17), Jack Russell Terriers (log OR = −1.88), and Rhodesian Ridgebacks (log OR = −1.88) were rarely affected. This contrasted with the well-known predisposition of Dachshunds and Rhodesian Ridgebacks to oral and cutaneous melanocytic neoplasms. Further studies are needed to explain the underlying reasons for breed predisposition or “resistance” to the development of specific acral tumors and/or other sites.

Recurrent bacterial pneumonia in Irish Wolfhounds: Clinical findings and etiological studies

BACKGROUND

Increased incidence of bacterial pneumonia (BP) has been reported in Irish Wolfhounds (IWHs), and recurrence of BP is common. The etiology of recurrent pneumonia in IWHs is largely unknown.

OBJECTIVES

To describe clinical findings in IWHs with recurrent BP and investigate possible etiologies.

ANIMALS

Eleven affected IWHs, 25 healthy IWHs, 28 healthy dogs of other Sighthound breeds, and 16 healthy dogs of other breeds.

METHODS

Prospective cross-sectional observational study. All affected IWHs underwent thorough clinical examinations including thoracic radiographs, thoracic computed tomography, electron microscopic evaluation of ciliary structure, and bronchoscopy and bronchoalveolar lavage fluid (BALF) cytology and culture. Serum and BALF immunoglobulin concentrations were measured using an ELISA method, and peripheral blood lymphocyte subpopulations were analyzed using flow cytometry. Esophageal function was assessed by fluoroscopy (n = 2).

RESULTS

Median age of onset was 5.0 years (range, 0.4-6.5 years), and when presented for study, dogs had experienced a median of 5 previous episodes of BP (range, 2-6). The following predisposing factors to BP were detected: focal bronchiectasis (10/11), unilateral (2/9) and bilateral (1/9) laryngeal paralysis, and esophageal hypomotility (2/2). Local or systemic immunoglobulin deficiencies or primary ciliary defects were not detected.

CONCLUSIONS AND CLINICAL IMPORTANCE

Recurrent BP affects mostly middle-aged and older IWHs without any evident immune deficit or primary ciliary defects. Focal BE was a frequent finding in affected dogs and likely contributed to the development of recurrent respiratory infections. Laryngeal and esophageal dysfunction identified in a minority of dogs may contribute to recurrent BP.

Characterization of Inflammatory Changes Associated with Canine Oligodendroglioma

Oligodendroglioma is a common glial tumour in the dog. In human neuropathology, the immune cell microenvironment of gliomas has been investigated; however, the nature of the inflammatory cells within canine gliomas is currently unknown. The aim of this study was to determine the nature of the immune cells and determine an association between the inflammatory cells and tumour grade. Thirty-four (18 of grade II and 16 of grade III) formalin-fixed and paraffin wax-embedded samples of canine oligodendroglioma were evaluated by light microscopy and immunohistochemistry for expression of CD3, PAX5, Iba-1, HLA-DR, Mac387 and CD31. Variations in immune cell recruitment and activation were evident in all cases. Infiltrating CD3(+) T lymphocytes were common in most cases. PAX5(+) B lymphocytes were less common and restricted to perivascular cuffs within or around the tumour. Iba-1(+) cells were common within the tumour and formed a dense infiltrate around the tumour in a subset of cases. HLA-DR(+) cells were common within the tumour and in a subset of cases formed perivascular cuffs. Iba-1(+) cells typically had prominent ramified processes suggestive of activated microglia, while the HLA-DR(+) cells had a more rounded morphology typical of amoeboid microglia. Rare Mac387(+) macrophages were found in the tumour parenchyma, while increased numbers of Mac387(+) monocytes were noted within the vasculature. No association or significance was established between the immune cell infiltrate and the grade of the tumour (all P ≥0.16). This study establishes that there is a robust population of immune cells within canine oligodendrogliomas and indicates that further study is needed to determine the role of these cells in tumour pathogenesis and progression.

A longitudinal assessment of periodontal disease in 52 Miniature Schnauzers

Background

Periodontal disease (PD) is the most widespread oral disease in dogs and has been associated with serious systemic diseases. The disease is more prevalent in small breeds compared to large breeds and incidence increases with advancing age. In prevalence studies 84% of beagles over the age of 3 and 100% of poodles over the age of 4 were diagnosed with PD. Current knowledge of the rate of progression of PD is limited. The objective of this study was to determine the rate of PD progression in miniature schnauzers, an at risk small breed of dog.

Dogs (n = 52, age 1.3-6.9 years) who had received a regular oral care regime prior to this study were assessed for levels of gingivitis and periodontitis around the whole gingival margin in every tooth under general anaesthetic. Assessments were conducted approximately every six weeks for up to 60 weeks following the cessation of the oral care regime.

Results

All of the 2155 teeth assessed entered the study with some level of gingivitis. 23 teeth entered the study with periodontitis, observed across 12 dogs aged between 1.3 and 6.9 years. 35 dogs had at least 12 teeth progress to periodontitis within 60 weeks. Of the teeth that progressed to periodontitis, 54% were incisors. The lingual aspect of the incisors was significantly more likely to be affected (p < 0.001). The severity of gingivitis in periodontitis-affected teeth was variable with 24% of the aspects affected having very mild gingivitis, 36% mild gingivitis and 40% moderate gingivitis. Periodontitis progression rate was significantly faster in older dogs. Only one dog (age 3.5) did not have any teeth progress to periodontitis after 60 weeks.

Conclusions

This is the first study to have assessed the progression rate of periodontitis in miniature schnauzers and highlights that with no oral care regime, the early stages of periodontitis develop rapidly in this breed. An oral care regime and twice yearly veterinary dental health checks should be provided from an early age for this breed and other breeds with similar periodontitis incidence rates.