They're carpeted and so that may make a difference, but our 75 and 80 pound pit bulls have no trouble going up and down them. They won't go up the steps to the flybridge, which are not carpeted.
Big dogs are the only way to go. With two protective pit bulls, we don't bother to lock the doors when we leave the boat. You can see how vicious they are. I put my guns in storage too.