My guess is that you moved to quickly to write down "feeding my dog." He was probably half joking and after the pause after he said "feeding my dog" was about to give you the real answer. When you wrote down "feeding my dog" and asked "What's Important About feeding your dog to you?" he probably continued to answer with responses about the dog to just mess with you. Two things to consider about this situation: 1. What if he was messing with you and you couldn't tell? 2. What if he was serious and you didn't respond with something to move him out of his ridiculous multiple response flow about the dog?
To point #1 above: part of asking good questions is developing a reasonable level of "people reading" skill. We aren't teaching to blindly march through the process and ignore all the signals people send you, besides their words, when they communicate with you.
To point #2: Remember, the formula: tell the truth, succinctly and directly, in a way that's all about them. eg: "I don't if you're serious about all these dog answers or not, but I get the point that you care about your dog. Besides your dog, What's Important About... To You?"