Budgerigar, Right testis, Sertoli cell tumor
Signalement: Budgerigar, male, adult, 50 gram
Diagnosis: Right testis: Sertoli cell tumor
Description: The right testis was enlarged and almost completely replaced by a well demarcated mass measuring approximately 3.6 x 2.5 x 2.0 cm. The mass was firm and on the cut surface whitish.
Comments: The bird was presented with progressive weight loss and euthanized with poor prognosis. No clinical signs of feminization (such as color change of the cere from blue to brown) were observed.
Necropsy revealed abdominal distension and displacement of abdominal organs by a large neoplastic mass expanding the right testis and partially infiltrating the left testis.
Histological examination confirmed the presence of Sertoli cell tumors, which were compressing the preexistent parenchyma. The tumor was composed of irregularly sized and shaped tubules separated by a moderate fibrovascular stroma and the remaining germinal epithelium was atrophic.
Testicular tumors are rare in birds. Reported tumors include seminoma, Sertoli cell tumor, interstitial cell tumor, lymphoma, undifferentiated sarcoma and teratoma. Seminoma and Sertoli cell tumor are the most common and have been mostly reported in caged psittacine birds, especially budgerigars.
Picture and author: Dr. Samoa Giovannini, Department of Veterinary Pathology, Freie Universität Berlin, Germany