Yeah in a fair chase in the open a big heavy dog won't catch a rabbit, they're not gonna be consistently running down rabbits, but circumstances can lead to it happening once in a while. Mind you, rabbits are nothing compared to jack rabbits and hares. You don't need a SUPER fast dog to catch them with some consistency. My late neo x shouldn't have been able to catch this (albeit mangy) fox, but he did- Didn't eat it though, luckily. Did eat this fella, and more like him. This photo is unusual because often all he left was clumps of fur and a neat little stomach pouch filled with vegetable matter.