Originally posted by Cap'n Bells:

SOLVED https://steamcommunity.com/profiles/76561197968876093/screenshots/ it might be Halstein or the wards but boars wont eat this close or breed. this is 1x1 square away.. now pen is 14x1 sq away and instant eating and piggy**

That was going to be my first guess that it was too close to his bubble which interferes with various things.

There are a few good videos too for breeding tames as with that small pen you're going to encounter some other limits(they'll stop breeding if more than 5 or so are so close). There are some really good pen examples with the breeding stalls set above to help keep the pig breeding(or wolf or lox depending on the set up) pretty much consistently ongoing.