Incidence of cryptorchidism in dogs and cats.

Over a period of 54 months, 3518 dogs and 3806 cats were castrated; 240 of the dogs and 50 of the cats were cryptorchid. Pedigree dogs, in particular the German shepherd dog, boxer and chihuahua were over-represented. Among the dogs, right-sided inguinal cryptorchidism was the most common form, followed by right-sided abdominal cryptorchidism. The location of the affected testicle(s) was most variable in the boxer. Among the cats, left- or right-sided inguinal cryptorchidism were the most common forms of the condition.