The presence of only one testicle in the scrotum is called cryptorchidism or testicular ectopia. Normally, a dog's testicles descend into the scrotum at two months of age, but in some cases, testicular descent can be a little slower. 

The first thing to do is to take your puppy to the vet as soon as possible so that, through a clinical examination and possibly an ultrasound scan, the vet can give you the most accurate advice.

What you need to know is that:
- it is not possible to make a definitive diagnosis before at least 6 months of age
- if, once development is complete, the testicle is not in the scrotum, the dog cannot be used for breeding
- surgical repositioning of the testicle is prohibited by law
- generally, the retained testicle must be removed, as it is more prone to developing tumors. However, this procedure is not urgent and can be performed after 12 months of age.

Call us for an appointment and we will evaluate the best strategy for your dog together.