protein source

["Louise Bower" <horsecrazy@access.mountain.net>]

I am interested in whey as a protein source.  I use COB and it is only 8% protein, so I want to add some protein not change my grain.  It is a straight grain mix with no additives or molasses.  I add my own supplements, and I don't know the % of protein of my hay, but it is orchard grass or timothy, no alfalfa.  I have found whey in the health food store, is this what I would use for the horse?  I have not seen any at my feed store.  I understand from another list that whey is an extremely good source of protein.  As the ridecamp gruru on nutition I would value your opinion.  Thanks, Louise