Yes, everyone is correct. The Great Horned Owl is a top predator, preys on what it wants to take to eat & is a danger to all poultry. They should be respected. There is an account on this forum of a full grown Pyrenees Dog taking on a Great Horned Owl that was attacking chickens. The dog eventually won but was cut up pretty good on its face. The OP described hearing her dog gowling and howling in a prolonged fight.
Great Horned Owls have been observed chasing Bald Eagles off their nests. And as the one poster stated, they are one of the few animals that eat skunks (and that is why a GH will often smell like one) & they will attack and kill a full grown opossum. A friend of mine lost all his ducks (one per night) to a GH. A Great Horned is one of the few birds of prey that is a danger to Geese too (the other being a Golden Eagle). Many folks around here loose their small dogs and puppies to GHs.
Great Horned Owls are federally protected and a permit would be needed to kill one.