Alfalfa Hay for Horses . How Much Alfalfa Do Horses Need? A horse needs a fairly small amount of protein per day. Roughly 3/4 to 1 pound of digestible protein (DP) will meet most horses’ daily requirement. This need can be met by supplying Alfalfa as half of a horse’s roughage. Feeding horses Alfalfa reduces or even eliminates the need for supplements which often have a laxative effect. Our commitment to supplying high quality Alfalfa year round gives horses a consistent and safe supply of protein. Do All Horses Need Alfalfa? Alfalfa is most beneficial for horses with high energy needs due to their moderate to high level of exertion. Alfalfa may provide too much energy, protein and nutrients for horses that are only occasionally exercised. Those horses that spend less than five hours a week performing low to moderate intensity activities, such as showing or recreational riding, do not require the high levels of nutrients that high quality Alfalfa supplies. A feed program for recreational horses should limit Alfalfa and include forage with high chew time, such as Timothy hay to combat idleness.