Undescended testicle - Page 2

Sometimes the puppies with the "late" testicles have had both all along. Vets are the absolute worst at finding testicles on puppies. Most stand them erect on all 4's,  you can't do that with most puppies. The testicles on an 8 week old large breed puppy are not much  larger than a pea and are hard to find if you don't hold the puppy the right way (and that's not standing him erect on a table). Toy breeds are even harder to feel.

When the inguinal ring closes the testicles are where they will always be. They then can't go back and forth from the scrotum into the abdomen. The ring is supposed to close by the time a male puppy is no older that 2 weeks of age. Some close a lot later allowing the testicle/s to yoyo back and forth. The most current thinking is that those dogs will probably be poor breeding risks due to late closure of the ring and they will pass that tendence on to their progeny.  If both testicles are in the scrotum when the ring closes, they will alwasy be there; if not, they won't. The 6 month old that suddenly drops a testicle either had it all along or is a dog with a ring that closed later then it should have. I've seen testicles trapped in the ring when it closed.

If you are a breeder and you breed puppies with retained testicles, if and when they are neutered it's smart to ask the vet why the testicle didn't descent. Sometimes the ligament is too short - genetic - but sometimes the ligament gets wrapped up somehow preventing the testicle from descending - probably not genetic. Other times there is no apparant reason for the retained testicle.

It is still not clear, but it seems that cryporchidism is inherited from both parents in a somewhat random fashion. A friend bred a litter, 4 males, all with both testicles early on; repeated the breed, again 4 males, none with both testicles. Go figure.........