Ridgling

A ridgling (also spelled ridgeling), or rig, is a cryptorchid; a male animal with one or both testicles undescended, usually describing a ram, bull, or male horse, but cryptorchidism also can be an issue in dogs and cats. Because the heat inside the body is too high for sperm to survive, an undescended testicle is non-functional. The condition is most often discussed in the horse world, as the health behavioral issues surrounding adult males with the condition are of concern to owners and handlers of such animals.