We feed our dogs dried food so enough of that gets thrown onboard for a few days or weeks. Ours dogs are too small to climb the companionway. I never thought about that as we have an old low freeboard boat which means it's only three steps up, or down the companionway ladder and an easy step from dinghy to deck. How high is the climb you have to deal with into the cabin?

The last big dog we had was a Springer Spaniel. He would climb extension ladders up two stories onto roofs, without fail. The only problem, I had to carry him down. He would have just skipped the steps on our companionway, going either way.