Q. I recently went to look at a horse that I was interested in buying. The man selling the horse told me that when the horse was gelded only one testicle had dropped. A friend who came with me to look at the horse told me to walk away because he was “proud cut” and could potentially become a danger to my other gelding. After doing research about the term “proud cut,” I found the horse is actually a cryptorchid. I really like the horse—should I not consider buying him?

—Ashleigh, via email

A. A cryptorchid is where one or both testicles have not fully descended into the horse’s scrotum. This retained testicle can be located just above the scrotum in the inguinal ring or in the abdomen.

The retained testicle is unable to produce spermatozoa due to the increased surrounding temperature (versus the cooler temperature surrounding a descended testicle) but is still hormonally active. The main hormone produced by the testicle is testosterone, which causes stallionlike behavior (for example, increased vocalization around mares, mounting of mares, aggressive behavior toward other horses, etc.) to be exhibited. This behavior often starts when the horse becomes sexually mature, around 2 to 3 years of age. Often this behavior is unacceptable to the majority of owners