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Retained testicle (Cryptorchidism) in pets

When an animal has an undescended or retained testicle, we call this condition cryptorchidism. Cryptorchidism is seen in both cats and dogs, as well as other animals. Although cryptorchidism rarely causes signs, the retained testicle may become cancerous. Here our vet advises what to look for and what to do if you notice that your cat or dog has a retained testicle.

This article was written by a FirstVet vet


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Cryptorchidism is the failure of one or both testicles (testes) to descend into the scrotum. The word is derived from Greek words crypto meaning 'hidden' and orchid meaning 'testicle' and can affect both cats and dogs. The testes develop near the kidneys within the abdomen. They normally move down into the scrotum at around two to four months of age. In certain dogs it may occur later, but rarely after six months of age.


Signs of cryptorchidism

Cryptorchidism rarely causes pain or other signs unless complications develop. If both testicles are retained, the dog or cat may be infertile. Complications to be aware of include:

  • Tumour: clinical signs will depend on the type of tumour
  • Twisting of the spermatic cord (spermatic cord torsion): severe acute abdominal pain


Diagnosis of cryptorchidism

Cryptorchidism is usually diagnosed if the testicles cannot be felt in the scrotum after six months of age. Your vet will examine your dog and try to locate the undescended testicle. The retained testicle(s) is usually found in one of three places:

  • Abdomen: testicle unlikely to be felt unless abnormally enlarged
  • Inguinal canal: passage through which a testicle normally descends from the abdomen to the scrotum
  • Under the skin in the groin area: between the inguinal canal and the scrotum


Treatment of cryptorchidism

Once cryptorchidism has been diagnosed, surgery is recommended to remove the affected testicle(s). Your vet will usually recommend scheduling the procedure when the pet is fully grown and sexually mature, which also gives more time to allow the testicle to descend.

Neutering a dog with a retained testicle is recommended for three reasons: cryptorchidism is a genetic defect and affected dogs should not be bred in order to prevent this inherited trait being passed onto the next generation. Secondly, it reduces the risk of testicular cancer, which is ten times higher in cryptorchid dogs than normal dogs. Thirdly, it reduces the risk of unwanted behaviours, such as urine marking and aggression. The prognosis is excellent for pets that undergo surgical treatment before complications arise.


Read more

Blue Cross: neutering myths debunked and neutering your dog


When to see your vet

  • If you are concerned that your dog only has one testicle visible or you can not see either testicle


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