Most of us could probably stand to eat a little more fiber, but our rabbits literally can't go without it — too little fiber causes their gastrointestinal system to shut down. (petconsider.com)
One is that since there is very little fiber in the ancestor of the domestic dog there is therefore no need for fiber in the diet of modern day domestic dogs. (wileypup.com)
This is especially true for sugar - loaded cereals that contain little fiber. (adventureblooms.com)