Before it got so high I fed newly weaned calves Purina Pre-Con. You could order it in bulk blended with Bovatec or Rumensin. Or with AS-700. But not both the growth stimulant and the anti-viral medication. Fed at about 2% of body weight per head per day I was getting average daily gains between five and ten pound range during the usual 21 day feeding period. It was expensive, but it got the calves to eating and the gains were outstanding. Never lost one to bloat.
About a half dozen years ago Purina priced it over $250/ton in bulk and I said that's enough of that. So I just put them on the usual ration of ground corn, soybean meal, soybean hulls and free choice hay. I blended a balanced mineral with Bovatec to the ground corn/sb meal mix and top dressed with AS-700 for 18 to 21 days. You don't want to go over 21 days with the AS-700 or you might cause damage to the kidney. I feed the corn mix and soyhulls starting at 4.5 pounds per head per day. I increase the feed in the steers and bulls 1/2 pound every two to three weeks up to 7.5 pounds of each. I usually never let the heifers have more than 5.5 pounds, so that they don't get fat.