The simple ten minute operation involves the removal of the stallions testicles by a veterinary surgeon - in our case this was our super vet called Anne. The operation is not reversible and the once my colt is gelded he will no longer be able to breed - which is exactly the result I wanted given that I have two mares at home.
Although the operation is only ten minutes, it is a good 45 minutes to an hour long to ensure that the colt is sedated then knocked out under anesthetic. We chose to do this in his field at home so he was safe to recover after and his day started out quite normally for him including eating his breakfast.
I have watched many operations on small animals such as neutering years before as my first weekend job with assisting in a vets when I was 14. In fact, I was interviewed for the job whilst the vet was spaying a cat and because I didn't pass out I was given the job there and then.
After I watched the operation - he was given time to come around. We'd had to delay the first op as the ground was so frozen and there was a risk he could develop hypothermia.
Luckily, all went well and fingers crossed he seems to be OK. They don't actually stitch the holes up to allow for drainage of fluid out of the area so I was given instructions to check for a lot of bleeding or bad swelling during the course of the next week. So he's now gone from a little foal to a proper little man. Ouch!
He felt a bit sorry for himself but he's back to his exuberant self playing with his horse ball in the field.