Search Results

Abstract

Objective—To categorize histologic lesions affecting the tongue, determine the frequency with which they develop, and identify risk factors associated with their development in dogs.

Design—Retrospective case series.

Animals—1,196 dogs.

Procedures—Diagnostic reports of lingual biopsy specimens from dogs evaluated from January 1995 to October 2004 were reviewed.

Results—Neoplasia comprised 54% of lingual lesions. Malignant tumors accounted for 64% of lingual neoplasms and included melanoma, squamous cell carcinoma, hemangiosarcoma, and fibrosarcoma. Largebreed dogs, especially Chow Chows and Chinese Shar-Peis, were at increased risk for melanoma. Females of all breeds and Poodles, Labrador Retrievers, and Samoyeds were more likely to have squamous cell carcinomas. Hemangiosarcomas and fibrosarcomas were commonly diagnosed in Border Collies and Golden Retrievers, respectively. Benign neoplasms included squamous papilloma, plasma cell tumor, and granular cell tumor. Small-breed dogs, especially Cocker Spaniels, were at increased risk for plasma cell tumors. Glossitis accounted for 33% of diagnoses; in most cases, the inciting cause was not apparent. Whereas large-breed dogs were more likely to have lingual neoplasia, small-breed dogs were more likely to have glossitis. Calcinosis circumscripta accounted for 4% of lingual lesions and predominately affected young large-breed dogs. The remaining submissions consisted mostly of various degenerative or wound-associated lesions.

Conclusions and Clinical Relevance—The frequency of lingual lesions was not evenly distributed across breeds, sexes, or size classes of dogs. Veterinarians should be aware of the commonly reported lingual lesions in dogs so that prompt diagnosis and appropriate management can be initiated.

Abstract

Objective—To describe the character and frequency of causes of death and associated lesions in long-distance racing sled dogs.

Design—Retrospective case series.

Animals—23 dogs.

Procedures—Medical records of dogs that died during or soon after competition in the Iditarod Trail sled dog races (1994 through 2006) were examined for findings of gross necropsy and histologic evaluation of tissue samples. From the data, descriptive and comparative statistics were obtained.

Results—Recognized causes of death included aspiration of gastric contents (n = 4), aspiration pneumonia (4), acute blood loss secondary to gastric ulceration (3), and sled dog myopathy (2). A cause of death was not established for 7 dogs. Prevalent lesions among the study population included rhabdomyolysis (n = 15), enteritis (10), gastritis (10), aspiration pneumonia (8), and gastric ulceration (8). All dogs with aspiration pneumonia had concurrent gastric mucosal lesions. Subjective biventricular cardiac hypertrophy was evident in most dogs; other lesions detected frequently included centrilobular hepatic fibrosis, gastric dilatation, and mild cardiac myodegeneration and necrosis.

Conclusions and Clinical Relevance—Unexpected death is a rare event among conditioned sled dogs during competition in endurance races. Potentially life-threatening conditions of dogs that are associated with periods of long-distance physical exertion include aspiration pneumonia, gastric mucosal lesions, and severe rhabdomyolysis. Dogs that develop clinical signs suggestive of these conditions should be excluded from strenuous activities. Epidemiologic investigations are required to clarify the risk for death associated with these lesions in dogs competing in endurance races.

Abstract

Objective—To identify epidemiological trends in cutaneous neoplasms affecting equids in central North America and compare them with previously reported trends.

Design—Retrospective case series.

Sample—3,351 cutaneous biopsy specimens from 3,272 equids with a neoplastic diagnosis.

Procedures—Diagnostic reports from 2 diagnostic laboratories (Colorado State University and Prairie Diagnostic Services Inc) were reviewed for frequency of specific lesions and epidemiological trends. Variables included in analyses (if known) were age, sex, breed, geographic location, date of diagnosis, location of neoplasm on the body, and presence or absence of ulceration.

Results—Sarcoid, squamous cell carcinoma (SCC), and melanoma were the 3 most common tumors diagnosed. Tumors associated with UV radiation (SCC, SCC in situ, hemangioma, hemangiosarcoma) were 2.3 (95% confidence interval [CI], 1.8 to 3.0) times as common in biopsy specimens received by Colorado State University than in specimens received by Prairie Diagnostic Services Inc. Appaloosa horses and American Paint horses, respectively, were 7.2 (95% CI, 5.6 to 9.2) and 4.4 (95% CI, 3.6 to 5.4) times as likely as other breeds to have tumors associated with UV radiation. Thoroughbreds were predisposed to cutaneous lymphoma, whereas Arabians were more likely to have melanomas. Draft and pony breeds were 3.1 (95% CI, 1.9 to 5.1) times as likely as other breeds to have benign soft tissue tumors. Morgans and pony breeds more commonly had basal cell tumors. Tumors in the perianal region were significantly more likely to be SCC or melanoma while tumors on the limbs were more likely to be giant cell tumor of soft parts.

Conclusions and Clinical Relevance—Signalment, anatomic location of the mass, and geographic location of the horse can be used to help equine practitioners formulate differential diagnoses for cutaneous masses. Further research is necessary to identify the biological basis for the development of many equine cutaneous neoplasms.

Abstract

Objective—To describe complications and outcome associated with chronic nonseptic pleural effusion treated with pleuroperitoneal shunts in dogs.

Design—Retrospective study.

Animals—14 dogs.

Procedure—Medical records at 4 veterinary schools were examined to identify dogs with chronic nonseptic pleural effusion that were treated by use of a pleuroperitoneal shunt between 1985 and 1999. Signalment, history, physical examination and laboratory findings, cause and type of pleural effusion, medical and surgical treatments, complications, and outcome were reviewed.

Results—10 of 14 dogs had idiopathic chylothorax, and 4 had an identified disease. All but 1 dog with idiopathic chylothorax and 1 dog with chylothorax from a heart base tumor had unsuccessful thoracic duct ligation prior to pump placement. No intraoperative complications developed during shunt placement. Short-term complications developed in 7 of 13 dogs, necessitating shunt removal in 2 dogs and euthanasia in 1. Eight of 11 dogs with long-term follow- up developed complications; the overall mean survival time and the interval in which dogs remained free of clinical signs of pleural effusion were 27 months (range, 1 to 108 months) and 20 months (range, 0.5 to 108 months), respectively.

Conclusions and Clinical Relevance—Pleuroperitoneal shunts can effectively palliate clinical signs associated with intractable pleural effusion in dogs. Numerous short- and long-term complications related to the shunt should be expected. Most complications can be successfully managed, but even when shunts are functional some treatments fail because of severe abdominal distension or massive pleural fluid production that overwhelms the functional capacity of the shunt. (J Am Vet Med Assoc 2001;219:1590–1597)

Abstract

Objective—To determine the suitability and estimate the sensitivity of an immunohistochemical (IHC) test for disease-associated prion protein (PrP^Sc) in biopsy specimens of rectoanal mucosa–associated lymphoid tissue (RAMALT) for diagnosis of scrapie in sheep.

Animals—762 sheep at high risk for having scrapie and indemnified by the National Scrapie Eradication Program.

Procedures—The IHC test for PrP^Sc was applied to 2 RAMALT and 2 third-eyelid biopsy specimens and a postmortem RAMALT specimen from each sheep. Results were compared with those of a reference test in which results for tissues from obex and retropharyngeal lymph nodes, tonsil, or both were considered in parallel.

Results—The reference test identified 139 sheep as having scrapie. Biopsy-related complications occurred in 3 sheep. Sensitivity of the IHC test in RAMALT ranged from 85.3% to 89.4%, depending on the anatomic location from which RAMALT was obtained. Results for the test applied to 1 RAMALT specimen were similar to results interpreted in parallel for 2 third-eyelid specimens (sensitivity, 87.0%). The proportion of inconclusive test results attributable to insufficient lymphoid follicles in biopsy specimens was lower when considering results for 2 RAMALT specimens in parallel (10.1%) than when considering results for 2 third-eyelid specimens in parallel (23.7%). Specimens of RAMALT that were inappropriately collected from an area caudal to the rectoanal interface yielded a high proportion of inconclusive results (33.3% to 50.0%).

Conclusions and Clinical Relevance—The IHC test for PrP^Sc in RAMALT was an effective means of detecting subclinical scrapie in live, high-risk sheep.