Cryptorchidectomy (removal of a retained testicle)
Joe (not his real name) was presented to Willamette Valley Equine for castration (gelding). However, Joe had one testicle that was not descended, but retained within the abdomen. In order to remove both testicles, Joe had general anesthesia and Laparoscopic surgery to remove the retained testicle. This procedure allows the retained testicle to be removed from the abdomen using an operating camera and long instruments placed into the abdomen through small incisions and the operation is viewed on a video monitor. Other methods of removal of a retained testicle must be accomplished through a larger incision and manual extraction of the testicle from the abdomen. The normally descended testicle on the other side is removed routinely through an incision in the scrotum.
The horse is anesthetized and placed on his back on the operating table for surgery. The abdomen is clipped and scrubbed and several small (1 cm) incisions are made for insertion of the instruments. The camera is inserted into the abdomen and the abdominal cavity inflated with carbon dioxide. The retained testicle is then identified in the abdomen. The testicle is grasped with long forceps and a loop of suture placed around the testicular cord and tightened. Laparoscopic scissors are used to sever the spermatic cord and the testicle is removed from the abdomen through a larger cannula. The small incisions are sutured closed and then the other normal testicle is removed routinely through an incision in the scrotum.
Common misconceptions about cryptorchid horses
1. Descent of the testicles from the abdomen occurs before birth. The testicles are not fully developed and often are found in the inguinal canal (a passageway from the abdomen to the scrotum) between the abdominal wall and the scrotum in the young colt. As they develop, they descend into the scrotum. Once the testicles descend from the abdomen, they cannot return to the abdomen. In some colts, however, they will remain partially developed in the inguinal area (a "high flanker"). In a horse with a retained testicle, the ligament that attaches the testicle to the epididymis is elongated. The epididymis (testicular vessels and spermatic cord) can descend into the scrotum or inguinal area and be mistaken for a testicle, while the testicle remains in the inguinal canal or abdomen.
2. Another common misconception is that if all the epididymis is not removed, the gelding can still exhibit stallion like behavior ("proud cut"): This scenario is impossible for 2 reasons: the epididymis is firmly attached to the normally developed testicle and is removed along with the testicle in a routine castration. In addition, the epididymis does not produce the hormone, testosterone, and cannot induce stallion-like behavior in a gelding even if part of it somehow was not removed. If the epididymis alone is removed from a horse with a retained testicle (the epididymis is mistaken for a small testicle) and the real testicle is left in the inguinal canal, then this horse is truly proud cut. Blood testosterone levels can be used to determine if a horse has retained testicular tissue.
If your colt has only one visible testicle in the scrotum, three scenarios are possible:
1. The testicle is still in the abdomen.
2. The testicle is in the inguinal region (high flanker).
3. The testicle never developed (very rare).
Laparoscopy is a valuable procedure used to determine where a retained testicle is located. Laparoscopic cryptorchidectomy can be performed when one or both testicles are retained in the abdomen. Laparoscopic removal of retained testicles allows the colt to return to activity faster due to the smaller incision size. Most horses are back to work or pasture in 2 weeks. Ask your veterinarian about this procedure and whether it would benefit your colt if he has a retained testicle.
