COB stands for corn, oats, and barley. It's sweetened with molasses and generally fed to horses.
Since American Guinea Hogs mostly forage for their own food, we use COB to call them to the barn at night. Overfeeding American Guinea Hogs causes them to become obese and can affect fertility so we have to be careful how much grain they get on a daily basis.
Bonnie and Bacon usually devour COB above all else!