Let their condition be your guide. Personally
I do not like alfalfa for horses. I would remove the alfalfa, add more
grass hay, and use beet pulp as required to keep weight on. You might even
consider adding a cup of oil to the dry beet pulp before soaking if more
calories are indicated.
Ed
Ed & Wendy Hauser 2994 Mittower
Road Victor, MT 59875