Koa, a 14-month-old mini horse weighing approximately 50kg, recently presented for castration. However, he was diagnosed as a rig (cryptorchid) due to one retained testis, which required surgical intervention.
Recently, Koa’s behavior had become problematic around mares and fillies, making the procedure necessary. The retained testis, located in the abdomen, required a full general anesthetic to locate and remove safely. This was expertly handled by Dr. Taylor Bunworth, who managed the clinical challenges and potential complications associated with anesthetising a horse of Koa’s size.
To prevent the risk of evisceration (intestinal prolapse), a potential complication in ponies and minis due to their large inguinal canal, a closed castration technique was used. The inguinal ring and canal were also surgically closed to eliminate this risk.
Interestingly, rigs often have a higher sex drive because the retained testis, being internal, is exposed to higher temperatures, which renders it infertile but still hormonally active.
The complexity of this procedure varies depending on the location of the retained testis – it can be just under the skin, in the canal, or even as high as the kidney where it originates during embryonic development. Every case truly is unique!
Koa is recovering well and should now be much calmer around his equine companions.
