Seth Petruzelli is a silverback who cares about other species of mammals.  He takes great umbrage at people who are cruel to dogs and has called out Michael Vick, the NFL quarterback who served time for pitting pitbulls against one another.  Seth issued the challenge on his Facebook page:

I'm making my official challenge to Michael Vick.  Any weight, 200 or above.. UFC, make it happen!

Who let the dogs out?  Seth Seth Seth Seth!