Hector the Bulldog
Hector the Bulldog is a character in the Looney Tunes franchise. He is an English Bulldog, usually the pet of Granny. He is muscle-bound and has grey fur (except for "A Street Cat Named Sylvester" and "Greedy for Tweety" where his fur is yellow-ish).
Normally, he clobbers Sylvester so he won't eat Tweety.