undescended testicle

In normal fetal development, the testicles develop in the abdomen and descend into the scrotum during the last months before birth. In a small percentage (3.4%) of newborns, one or both testicles fail to descend into the scrotum. In 80% of cases, the undescended testicle migrates into the correct position without intervention during the first year. The condition occurs in both testicles in about 10% of cases.

This condition is known as "cryptorchism". Failure to correct this condition is met with a significant increase in the risk of malignancy (testicular cancer) in the undescended testicle.

The prodecure to correct cryptorchism is called "orchidopexy". An inguinal incision is made and the undescended testicle, with its vascular and vas deferens pedicle are tunneled into the scrotum.

An undescended testicle is a common occurence in the canine species. Such an animal is known as a "monorchid". A dog with only one testis descended into the scrotum cannot be entered into the conformation section of a dog show. He may, however, participate in obedience trials.

This conformation restriction is because the reproductive abilities of the monorchid are questionable. The condition does not inhibit either sexual desire or copulation ability. In certain breeds even neutering will not stop this biological instinct.