Horses: Unilateral Castration Contraindicated and Expensive

Horse which have only one testicle removed (by unilateral castration), frequently as a result of failing on cryptorchidism identification before a surgical castration, is a costly and unethical practice occurring too often according to researchers.

David Moll, DVM, MS, Dipl. ACVS and colleagues at the Oklahoma State University College of Veterinary Medicine, defined the incidence of cryptorchidism and unilaterally castrated horses and have lately discussed their findings in a study published in Journal of the American Veterinary Medical Association. The researchers also collated the cost of diagnosing and treating these horses.

Between January 2002 and December 2006, 160 horses were taken to Oklahoma State for castration. Of the total, 16 (10%) of horses had been unilaterally castrated formerly, and 44 (27.5%) were diagnosed with cryptorchidism and sent for complete castration.

The horses referred for cryptorchidism had 2.36 years old (average), while unilaterally castrated horses were (4.09 years) prior the treatment. No other meaningful differences in the distribution of retained testicles were recorded except for more right inguinal testicles on unilaterally castrated horses compared to cryptorchid horses.

Unilaterally castrated horses were more expensive to diagnose and treat. The average cost of a standard cryptorchid surgery was about 22% less expensive than surgery performed on unilaterally castrated horses, in addition to money anteriorly spent by the owner on the original unilateral castration or additional diagnostic procedures performed before referral.

"Horses that are unilaterally castrated may continue to exhibit stallion-like behavior, and can be a diagnostic and surgical challenge," informed Moll.

Also, Moll suggested that unilateral castration is amoral, resulting in a significant economic loss to the owner, and pointlessly exposes the horse to additional anesthetic, sedation and surgical episodes.

The paper "Comparison of the diagnosis and management of unilaterally castrated and cryptorchid horses at a referral hospital: 60 cases (2002-2006)" was published September 15, 2007 in the Journal of the American Veterinary Medical Association. Contributing authors were Moll, Marshall, BVMs, and Moorman, DVM.