I may shock a few of you with this, but here in the states we (some of us) let our pigs have "free choice feed" that means we keep the hopper always full and they can eat when ever they like.
Also, the pigs that have this option, have access to lush pasture, so they have a lot more activities to keep them from just keeping their snouts in the grain. This is also how I feed all my dogs
. When fed this way from birth, they don't feel the need to over eat. The dogs are always happy and lean (not fat), the pigs are the same way. When the pigs get about 100# or so, we start feeding them a measured ration. Works very well. Just thought I would offer up a little diversity
.