If you're talking about a checked bag, you can bring whatever you want as long as the destination and any layovers don't outlaw it. You just need to inform them ahead of time.

I once heard a rumor of a guy that had a gun in his checked baggage and his flight had an emergency layover somewhere. Apparently the location of the emergency layover didn't like what he was carrying and he was arrested as soon as the plane touched down. So you should probably watch out for that too.