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This information is provided by Provet for educational purposes only.

You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

When one or both testicles fail to descend into the scrotum it is called crytporchidism....but does it matter ?

During foetal development the testicles develop high up in the abdomen - near the kidneys. In most domesticated species (horses, cattle, sheep and pigs) by the time male animals are born   the testicles have moved backwards and have already descended into the scrotal sac. In dogs they descend within 5 days of birth. 

If they do not descend testicles may be retained in the inguinal canal (in the groin) or within the abdominal cavity itself. Retained testicles are always smaller than descended testicles and they are unable to produce sperm because they are not kept at the correct temperature

A cryptorchid animal with one descended testicle is not sterile and it is quite able to sire youngsters. On the other hand hormone production by the retained testicle can continue as normal, so the animal retains male characteristics and behaviour. However, the trait to develop undescended testicles  is thought to be genetically  inherited so affected animals should not be used for breeding.

One of the physiological purposes for the scrotum is to keep the testicles outside the body and at a lower temperature than they would be if kept inside the body. One consequence of being retained (and therefore being  kept at a higher temperature) is a failure of the testicle to be able to produce sperm. Another, is the tendency to develop cancer. The risk of developing testicular cancer is extremely high in retained testicles. 

Neutering (castration) is recommended to :

  • Prevent transmission of the cryptorchidism to offspring
  • Prevent the development of testicular cancer in the retained testicle(s)


Updated October 2013