That's pretty close to what I feed mine. The feed's from a different place (Schulte Farm Services at Independence), but the same amount. I also keep a protein tub out for them, and they have free choice salt and mineral. When grass comes out in the spring I stop the feed and protein tub. I'll have them palpated this fall, and then the ones I'm keeping go in with the mature cows. Most people will disagree with me, but I sell the calves when they're 60-90 days old so the heifers can grow out better and the calves won't pull them down. They'll usually breed back quicker also when the calves are pulled.
When you're going to breed them will affect how you should treat them. Mine were weaned last summer, so they're about 13-15 months old now. I'll put a bull on them about the end of this month.
Have they been wormed recently?