If your stallion needs to have a testicle removed due to disease, neoplasia (tumor), or severe trauma, don’t worry: Stallions can still lead productive lives as studs with only one testis, assures a researcher from Texas A&M University.

"Clinical experience suggests that unilateral orchiectomy of a diseased or traumatized testis is fairly common in breeding stallions," said Justin McCormick MS, DVM, of the school’s Department of Large Animal Clinical Sciences, in his presentation at the 2012 American Association of Equine Practitioners’ Convention, held Dec 1-5 in Anaheim, Calif.

McCormick explained that even wasn’t clear if sperm quality decreases following the removal of one testis, the research community recommends sexual rest for at least one spermatogenic cycle (about 12 days). However, a postoperative period of sexual rest following unilateral castration during the breeding season can negatively impact a stallion’s economic productivity due to lost breeding opportunities.

McCormick and his colleagues compared two different unilateral castration procedures to determine if one technique was more damning on sperm quality than the other.

"We performed unilateral castrations on nine Miniature Horse stallions using either a ‘first intention’ or a ‘second intention’ procedure to close the scrotum," explained McCormick.

First-intention healing means that the surgical incisions created to remove the affected testicles were sutured closed, and second-intention healing means that the incisions were left open to drain.

McCormick and his colleagues eva