Depends on how the pigs are raised and what supplements or additives they may be fed. But adding to an active compost pile should neutralize most everything. But rabbit manure is typically considered pretty safe, both wrt to any additives (few, if any) and the fact that it does not need to be composted before application. One of the few animal manures than can be applied direct from the source :-))

Yeah, depends a lot on how the pigs are raised. And also, depends on what you mean by composting. As in an active, hot compost pile that gets turned/tended? Or the pile left out on the back 40 somewhere to sit for a while with heaps of other stuff? Both methods can work, but take a different amount of time to compost up.

Rabbit poo is pretty safe like gardengal said too. I don't have rabbits, but know a couple people that do, they say it works fine.