Nope! To increase weight on any cattle, animals need protein, and other basic nutrients. Grass hay can vary from almost zilch nutrients (except roughage, which they definitely need) to protein content in the upper teens or higher. Alfalfa hay has a very high nutrient level, but don't overfeed it. The special bagged feeds sold by such companies as Purina, Nutrina, Hi-Pro and others are excellent supplements to hay and/or pasture. We feed this to our calves after weaning (about 2-3 lbs a day) along with a few 20% range cubes, some bermuda pasture, and 1-2 flakes of alfalfa daily, along with molasses mineral tubs. Ours have excellent condition and conformation, if I do say so myself. We're looking at "balanced nutrition" here with all the necessary minerals to boot. You can view some of the results on this type of feeding program by viewing our cattle website: <A HREF="http://www.runningarrowlonghorns.com" TARGET="_blank">www.runningarrowlonghorns.com</A> and you can judge for yourself! Have a good one!