Interesting list, and worth linking to as I wouldn't deliberately introduce anything poisonous next to pigs.
However I'm never sure who complies these lists.
I have used pigs to clear an ivy floor in a wood (Ivy is on the list), they simply dug the stuff up, and it is now glorious bluebells and other plants.
Rhodies are not on the list, but frequently quoted as poisonous, we have friends with 100 pigs in a wood stuffed full of Rhodie, they love it for shade
Another set of friends have theirs in an area with bracken in it (again on the list) - they simply ignore it.
Ragwort is also quoted some places as poisonous, again never seen anyone have this as a problem, and plenty of people have ragwort dotted around.
I think pigs are generally pretty cute on what they eat, and I'm not sure quite how anyone gets to a definitive list of what is poisonous.
After all on all medical definitions alcohol is poisonous to humans !