A 7-month-old male domestic ferret (Mustela putorius furo) was presented for evaluation of unilateral testicular enlargement. Microscopic examination of the left testicle revealed a neoplasm with differentiation along multiple cell lines (ectoderm, endoderm, mesoderm) including respiratory epithelium, bone and haired skin. A poorly differentiated epithelial component was dispersed throughout the neoplasm with invasion of testicular lymphatics. The animal developed progressive dysuria and was euthanized. At necropsy, metastasis of the poorly differentiated epithelial component was present in the urinary bladder, ureters, prostate gland, pelvic fat, abdominal and thoracic lymph nodes, kidney and lung. This is the first report of a malignant testicular teratoma with widespread metastasis in this species.

一只 7 个月大的雄性家养雪貂 ( Mustela putorius furo ) 被送去评估单侧睾丸增大。左侧睾丸的显微镜检查显示肿瘤沿多种细胞系（外胚层、内胚层、中胚层）分化，包括呼吸道上皮、骨骼和毛发皮肤。分化差的上皮成分分散在整个肿瘤中，侵犯睾丸淋巴管。该动物出现进行性排尿困难并被安乐死。尸检时，低分化上皮成分的转移存在于膀胱、输尿管、前列腺、盆腔脂肪、腹部和胸部淋巴结、肾脏和肺中。这是该物种广泛转移的恶性睾丸畸胎瘤的首次报道。