I have large blacks as well, and don't have any problem with them and other animals. The chickens are always in their pen picking around and are never bothered by the pigs. The cats sleep with them and they hang with the cattle. I had a few piglets escape and spend the day exploring/wandering through the coops and cow sheds before deciding to go back over the pen fence at feeding time and no harm done. (they are yarded during the winter)
My perimeter fences are good so I don't care if something gets out of its assigned slot for a bit of a walk about and all of my animals know each other. Even the horses meet the pigs as the winter pig pen is in the middle of everything and the fence is only 2 feet tall.
I would not keep them in my horse pasture though since the horses are dominate and like to play foot ball with anything smaller then they are. Since I know the horses chase the poultry, dogs ect... I would not risk pigs; even though they are large, they can't move fast. Horses are also hard on a pasture and would be bad in combination with pigs rooting. I also, would not keep them in with the cows at calving time since that is when the cows jump on everything that moves.
During the summer my pigs share the pastures with the cows and chickens. Since my boar cannot be kept with the sows when they are open, he is much happier if he has company of some kind and does well with the angus during those times and doesn't leave them to find other company.
Large blacks are a very docile breed; mine are raised from birth with other animals and so far have not been inclined to eat them or me.