Do not feed medicated starter to cocci vaccinated chicks. Apparently the combo makes chicks more susceptible to cocci.I found a stiff dead chick tonight. I saw a little blood by its ear, I wonder what happen. I heard it chirping or crying, but did not check up on him until a little latter. I felt like something was wrong, so I went outside to check my brooder and it was dead. I ordered them to be vaccinated and I am feeding medicated chick starter. Not sure what to make of it. The rest running around, and look healthy.