Aloha,
Here in Hawaii we catch young boars, then "Lauhole" (castrate) them and set them free. Without there nuts they can't produce Keiki's. They put on much more fat as they grow and there meat don't smell. I always tag my Lauhole's to see if I catch them later, some of my friends do the same. We have different tags so if we catch each other's Lauhole's we note where it was caught and how heavy it was.
On average the Lauhole's are about 50 pounds heavier than the un-Lauhole of the same litter.
Aloha, Keone