Cryptorchidism in Horses: Welfare and Surgical Management

Cryptorchidism (retained testicle) in horses requires surgical removal. Welfare considerations cover both the retained testis complications and the surgical procedure itself.

Key Facts

Cryptorchidism occurs in approximately 2-8% of male horses — one or both testes fail to descend
Retained testes produce testosterone causing stallion-like behavior in geldings
Retained abdominal testes are at higher risk of testicular torsion — a welfare emergency
Surgical removal (cryptorchidectomy) requires general anaesthesia with higher risk than routine castration
Laparoscopic surgery is increasingly the preferred approach for abdominal retained testes

Welfare Challenges of Cryptorchidism

Cryptorchidism creates welfare challenges both from the retained testis itself and from the behavioral consequences of ongoing testosterone production. Horses with incomplete castration — where a retained testis was missed at primary surgery — continue producing testosterone, maintaining stallion behavior. This behavioral profile creates management difficulties, dangerous interactions with mares, and potentially affects the horse's ability to live in appropriate social groups.

Testicular torsion of a retained abdominal testis represents an acute welfare emergency. The twisting of the blood supply to the retained testis causes severe, sudden abdominal pain indistinguishable from acute colic. Emergency surgery is required — delayed treatment causes irreversible testicular necrosis and systemic toxemia.

What You Can Do

Have any horse with stallion behavior after castration tested for residual testosterone
Seek specialist surgical referral for cryptorchidectomy — abdominal retained testes require laparoscopy
Treat sudden severe colic in horses as a potential torsion emergency if cryptorchidism is known
Ensure surgical team is prepared for general anesthesia risk in cryptorchidectomy procedures
Monitor for signs of internal bleeding post-operatively — a risk in abdominal surgery