Diphallia in a Mixed-Breed Puppy: Case Report.

An 8 mo old intact male mixed-breed dog presented for diphallia with paraphimosis of the nonfunctional, accessory penis. Bloodwork, an abdominal ultrasound, and a positive contrast retrograde urethrogram were performed and revealed no other structural abnormalities. Surgical excision of the accessory penis was elected. This is one of three reported cases of diphallia in the dog in the English literature, but this is the only case in which no other congenital abnormalities were identified. The authors also review diphallia in both the veterinary and human literature.