When a horse or pony founders, the signs seen are the result of both front hooves being sore (the back hooves are also often involved but because the front legs take for more weight, they show more pain).
Castration involves the surgical removal of a male horse's testicles. This operation is performed under anaesthetic (either local anaesthetic while the horse is standing, or general anaesthetic with the horse lying down fully asleep) to avoid any pain for the horse.
Herpes viruses have the ability to live in a host (animals or humans) for very long time periods without causing disease. Under certain conditions (stress), they emerge from the cell they are in and can be shed into the environment to infect others. This has been shown to occur with EHV1 in horses.
This frustrating condition can occur in any age, breed or sex of horse. It is often worse with exercise.
This often chronic condition affects the area behind the pastern, but may extend to above the fetlock and around the sides of the lower leg - from one to all four legs may be affected.