Animator Sydney Padua, in her blog, draws some insights about how different animals walk [click through, to get to her blog, and see the images much larger, and so read the writing that accompanies each drawing]:
Here’s some of my notes on four-legged walks (our feature animal: COWS!) for a class I’m teaching at the Animation Workshop, for those who might find it useful– as always, study as much as you can from reference and understand WHY the action is as it is.