Cryptorchidism is the retention of the testicles in male horses. There are several different types of cryptorchidism based on the degree of retention:

The hardest type to deal with is a complete abdominal retention. With this, the testicle is fully retained in the abdomen, and is mobile within the abdominal cavity. Typically this testicle will be small and flabby. It is extremely unlikely that it will produce sperm, although there has been one case reported. The sperm in such a case would not be fertile. The testicle is not externally palpable.


Incomplete abdominal retention is only marginally easier to deal with, in that the retained testicle is not mobile within the abdominal cavity, but is usually located close to the deep inguinal ring, with portions of the testicles attached tissue passed through the vaginal ring, where they can sometimes be palpated externally with the horse standing, and often when the horse is laid down under anesthesia.


Permanent inguinal retention is where the testicle has descended through the deep inguinal ring, but is trapped within the inguinal canal. It is difficult or impossible to palpate, and may be palpable upon the horse being laid down under anesthesia. Caution should be used in that it is possible to mistake the results of this palpation for those of an incomplete abdominal retention. In both instances the tail of the epididymis within a vaginal process may be felt. Either testicle can be retained, with the other testicle also sometimes being retained abdominally. An animal with this condition is sometimes known as "high flankers".


Temporary inguinal retention is the condition that holds the most hope for the horse's owner. The retained testicle may be palpable within the inguinal canal with the horse standing, but will certainly be palpable with the horse laid down under anesthesia. The right testicle is the one most commonly affected (in more than three-quarters of cases). With this type of retention the testicle will usually descend of it's own volition by the time the colt is three years of age, although cases of it not descending until the horse is six have been recorded. In this type of retention, the testicle can sometimes be aided in it's descent by treating the animal with hCG (human chorionic gonadotropin), which will artificially stimulate the natural testosterone production, thereby encouraging descent.

© 2000 Jos Mottershead and Equine-Reproduction.com

Thanks for posting those information regarding this kind of disease. As of the moment, I'm glad that our male horse doesn't have that kind of sickness. Other than going to a vet, what is the first aid we can do if ever we have seen these symptoms in our horses?