Cryptorchidism refers to a condition where one or both testicles have failed to descend into the scrotum. In normal dogs, the testicles that developed from gonad cells in the abdomen will migrate to the scrotum. This arrangement is necessary to maintain scrotal temperature which needs to be slightly lower than body temperature. Normal body temperature will lower sperm count and will prevent the spermatozoa from being sufficiently matured for effective fertilization. Unlike human testicles that should have descended at birth, dog testicles will stay hidden in the abdomen when the dog is born. The testicles will move down to the scrotal sack 4 to 7 weeks after the dog’s birth. If one testicle or both testicles have failed to move down when the dog hits the 2 months mark, the descent is most unlikely to happen. The dog will be considered a cryptorchid.

This condition that is quite common in dogs and in other mammals is an inherited trait. Cryptorchidism is often associated with genetic mutation. There are various reasons why the testicles of the dog would not travel to the scrotal sack as it is supposed to. Cryptorchidism can be due to intersex condition. A problem could have occurred while the reproductive system of the dog is being formed. Undescended testicles may remain in the abdomen or may have been stuck on its way to the scrotal sack and remained in the inguinal canal. Undescended testicles are commonly undeveloped and non-functional. Sperm will not be produced in testicles situated on the wrong part of the body. The condition can lead to serious concerns later in the dog’s life.

The dog can develop a condition known as testicular torsion. Because the undescended testicle will not be confined and held tightly inside the scrotal sack, its movement will not be limited. These movements can cause the spermatic cords to twist cutting off the oxygen and blood supply. This is a serious condition as without nourishing blood and oxygen, the testicle will die. The dog will be in severe abdominal pain so that it would cry when the abdomen is touched. Affected dogs will vomit, have no appetite and pant excessively. Dogs with intact testicles have a 10% risk of developing testicular cancer. This is the reason why dog experts would advise owner that have no plans of breeding to have the pet neutered. Cryptorchid dogs’ risk of developing testicular cancer is 13% higher than dogs with normally descended testicles. Cryptorchid dogs are prone to develop three kinds of tumors. Steroli cell tumors, Leydig cell tumors and Seminomas are cancerous growths common in dogs with undescended testicles. Leydig cell tumors develop from the mutation and replication of the cells that regulates the production of the testosterone. This kind of growth is commonly benign and rarely spread to other parts of the body. A cryptorchid dog will develop steroli cell tumors when the cells that help spermatozoa to mature mutate and replicate. Estrogen is a hormone typically produced in female dogs although male dogs also have this hormone in small quantities. Steroli cell tumors cause the excessive production of estrogen in cryptorchid dogs. Anemia, bone marrow hypolasia and the development of prostate problems are commonly associated with estrogen toxicity. Dogs with undescended testicles will produce high levels of testosterone. This condition will result to the development of prostate problems and perianal tumors. The dog may also suffer from sexual dysfunctions. Seminomas develop from the mutated cells that produce sperms. Both the steroli cell tumors and the seminomas can develop to the size of basketball. The possibility that these tumors will metastasize to other parts of the body is high. Crytorchidism cannot be prevented but the condition can be easily resolved with castration. The surgical procedure will remove booth the normal testicle and the undescended one.