Wintering Early Weaned Calves at Mickey's

We early weaned 172 head of calves in October and hauled them to Mickeys. They had an average weight of 328 lbs. We moved them back to the Goat Ranch on April 20, and they had an average weight of 444 lbs, for an adg over the 180 days of .64 lbs...awful. We supplemented some ddg (guessing 2-3 lbs per day) and lost 4 head (we hauled 168 head back to the Goat Ranch)...a 2.3% death loss. Awful. I'm not sure why we can't get better gains, but this is discouraging considering we are moving to a stocker program that will utilize stockpiled forage for the first couple of months. I'm hoping poor genetics (all calves were first calf heifers calves) and poor grass at Mickeys were to blame. I'm still hoping we can get 1.5 lbs adg in our stocker program....we'll be finding out soon enough.