[Toadies]

Pigs chew, as you know, so if you can keep access to the wood away from them, it would be best. Putting your screening, preferably with a small grid, on the inside of the supports would keep theit little teeth farther away from temptation. A dry wood (like beech, birch, oak) has less oils and, consequently, is safer for the little guys. Wood is famous for absorbing moisture (pee, water), so research on animal-safe sealers available in your area would be a good idea.