We put pigs together into a pen for the first time, and the mamma fights another pig for dominance while her piglet tries to nurse. Get out of the way piglet!
This lasted for about 5 minutes, then we never saw them fight again, except the usual little skirmishes around food.
It looks kinda tame, but when we were there, there was an intense electricity in the air, you could feel! Remember, these are several hundred pound beasts!