The babies that I had turned out to be good feeders, even the slower ones. I sold those guys only by coincidence. However if I had say 5 or 6 babies I was trying to choose my holdbacks from. If all things considered they were all similar quality, I would probably opt to keep the ones that were the best feeders right off the bat if I couldn't keep them all. Just my opinion. Try these techniques and like Raul said, leave them alone and be patient.