Dermoid sinus in a golden retriever

A case of dermoid sinus is reported in a golden retriever. The skin lesion was characterised by a fistulous tract in the dorsal cervical region. Surgical dissection revealed a cyst connected by a fibrous cord to the seventh cervical vertebra.     

Oronasal blastomycosis in a golden retriever

Blastomycosis is one of the most common systemic fungal infections in dogs in North America Pulmonary manifestations are most common; localized disease is rare. A case of localized oronasal blastomycosis mimicking oral neoplasia is described. Long-term therapy with itraconazole resulted in clinical cure.     

Cerebral ganglioneuroblastoma in a golden retriever dog

An 8-month-old Golden Retriever dog was euthanatized because of a large cerebral mass extending from the right frontal lobe to the thalamus that was composed of both mature and immature neuronal cells. The better differentiated cells had abundant eosinophilic cytoplasm with prominent Nissl substance and were generally positive for neurofilament and variably positive for synaptophysin. The generally smaller and less-differentiated cells were infrequently positive for proliferating cell nuclear antigen and were negative for any neuronal and glial markers. No apparent glial differentiation of the immature tumor cells was detected. Based on morphologic and immunohistochemical features, the diagnosis of cerebral ganglioneuroblastoma was made. This neoplasm is very rare in all species, especially in the central nervous system, and has never been reported previously in this site in a dog.     

Multifocal osteoma cutis in a golden retriever

A 10-year-old, spayed female, obese golden retriever, presented for immune-mediated thrombocytopenia, was successfully managed with the administration of vincristine and prednisone. However, 6 mo after discontinuing corticosteroid therapy because of suspected iatrogenic hyperglucocorticoidism, the patient was presented with multiple, firm, bilaterally symmetric, dermal masses composed histologically of differentiated cortical bone.     

Renal nephroblastoma in a 3-month-old golden retriever

Nephrectomy was performed in a 3-month-old intact female golden retriever dog for a renal nephroblastoma. The dog has remained disease-free for 19 months with nephrectomy alone. The adoption of human Wilms’ tumor grading criteria may be useful in determining clinical stage, adjuvant treatment options, and prognosis in this rare disease.     

Uterine carcinoma in a 10-month-old golden retriever

A 10-month-old golden retriever was presented for investigation of reduced appetite, occasional vomiting and general dullness. Abdominal radiography demonstrated a large mid-abdominal soft tissue mass. Exploratory laparotomy identified a uterine mass, which was removed surgically. Histopathology confirmed uterine adenocarcinoma. Adjunctive chemotherapy with epirubicin was performed. The dog remained clinically normal without evidence of metastatic disease 24 months after surgery. Canine uterine adenocarcinoma is an extremely rare tumour and, as far as the authors are aware, this is the youngest reported case to date.     

Genetic management of Dutch golden retriever dogs with a simulation tool

Excessive inbreeding rates and small effective population sizes are an important problem in many populations of dogs. Proper genetic management of these populations can decrease the problem, and several measures are available. However, the effectiveness of these measures is not clear beforehand. Therefore, a simulation model was developed to test measures that aim to decrease the rate of inbreeding. The simulation program was used to evaluate inbreeding restriction measures in the Dutch golden retriever dog population. This population consisted of approximately 600 dams and 150 sires that produce 300 litters each year. The five most popular sires sire approximately 25% of the litters in a year. Simulations show that the small number of popular sires and their high contribution to the next generation are the main determinants of the inbreeding rates. Restricting breeding to animals with a low average relatedness to all other animals in the population was the most effective measure and decreased the rate of inbreeding per generation from 0.41 to 0.12%. Minimizing co‐ancestry of parents was not effective in the long run, but decreased variation in inbreeding rates. Restricting the number of litters per sire generally decreased the generation interval because sires were replaced more quickly, once they met their restriction. In some instances, this lead to an increase in inbreeding rates because the next generations were more related. The simulation tool proved to be a powerful and educational tool for deciding which breeding restrictions to apply, and can be effective in different breeds and species as well.     

Peripheral hypomyelinization in two golden retriever littermates

Peripheral hypomyelinization was found in 2 Golden Retriever littermates that had pelvic limb ataxia, depressed postural reactions, and depressed segmental reflexes. Diagnostic findings included infrequent denervation potentials, reduced or absent evoked potentials, and markedly diminished motor nerve conduction velocities. Light and electron microscopy of peripheral nerves revealed fewer than normal myelinated axons, myelinated sheaths inappropriately thin for the caliber of the fiber, poor myelin compaction, greater than normal numbers of Schwann cell nuclei, many Schwann cells with voluminous cytoplasm, and greater than normal amount of perineural collagen. Findings were compatible with a peripheral hypomyelinization process; a defect in Schwann cell function was suspected.     

Idiopathic Horner's syndrome in the golden retriever

A prospective study was made of cases of idiopathic Horner's syndrome in dogs referred to the author. Over a six-year period the condition was recorded in 62 golden retrievers. Examination suggested that the lesions affected the preganglionic neuron.     

Congenital hypomyelinating polyneuropathy in two golden retriever littermates

Serial peripheral nerve biopsies from two golden retriever littermates with chronic neurologic disease were taken for morphologic and morphometric evaluation. Teased nerve preparations were difficult to interpret due to the lightness of myelin staining. Light and electron microscopic findings were characterized by the following: reduced number of myelinated axons, presence of myelinated sheaths inappropriately thin for the caliber of the fiber, poor myelin compaction, increased numbers of Schwann cell nuclei, increased concentration of neurofilaments in myelinated axons, many Schwann cells with voluminous cytoplasm, and increased perineurial collagen. Onion bulb formation was not seen. In contrast to control data, a poor correlation was seen between numbers of myelin lamellae (ML) and axonal circumference (AC). The frequency distribution of ML ranged from 5 to 55 lamellae in affected animals (mean, 28 lamellae) compared to 20 to 140 lamellae in controls (mean, 66 lamellae). The ML/AC ratio was significantly reduced (P less than 0.001) in nerves of affected dogs. Morphometric results indicated that fibers of all calibers were hypomyelinated.     

Immune-mediated haemolytic anaemia associated with a sarcoma in a flat-coated retriever

A seven-year-old flat-coated retriever presented with a history of lethargy, dyspnoea and inappetence of several days' duration. Clinical examination revealed pale mucous membranes and tachypnoea, and haematology demonstrated marked autoagglutination. Thoracic radiographs revealed an increased opacity in the perihilar region. The owners declined further evaluation and the dog was treated symptomatically with immunosuppressive doses of prednisolone and azathioprine. The dog's demeanour improved, although it was eventually euthanased seven weeks later because of dysphagia and worsening dyspnoea. Postmortem examination revealed a widespread, poorly differentiated sarcoma involving the lungs, pericardium, thoracic lymph nodes and spleen. Immune-mediated haemolytic anaemia is a well recognised condition in dogs and is occasionally associated with neoplastic conditions. This is the first case report to describe immune-mediated haemolytic anaemia associated with a diffuse, poorly differentiated sarcoma.     

Choanal lymphosarcoma in a 7-year-old golden retriever: diagnosis and treatment

A 7-year-old, spayed female, golden retriever with a 1-year history of progressive stertor and reverse sneezing was referred for further diagnostics. Endoscopy and computed tomography of the head revealed a bilobed mass in the choanae. Cytologic and histopathologic examinations of the mass were consistent with lymphosarcoma. Treatment consisted of chemotherapy.     

Surgical management of subvalvular aortic stenosis and mitral dysplasia in a golden retriever

A 12monthoid neutered male golden retriever was presented with a history of lethargy and exercise intolerance. Clinical examination, electrocardiography, radiography and echocardiography supported a diagnosis of fixed subvalvular aortic stenosis with a Doppler pressure gradient of 77.5 mmHg. Surgical inspection also revealed gross structural abnormalities of the mitral valve consistent with mitral dyspiasia. intervention consisted of resection of the dysplastic mitral valve and the subvalvular aortic stenosis. The mitral valve was replaced with a bioprosthetic valve. Total cardiopulmonary bypass time was 65 minutes and aortic crossclamp time was 55 minutes. A full recovery was made and 11 months postoperatively the aortic transvalvular gradient was 30 mmHg. At the time of writing, 12 months after surgery, the dog was clinically normal and requires no medication.