My opinion is the cracked corn started the problem by making them weak do to lack of protein which is mostly what they need. Without grit and the lower protein they were barely getting by. Then you said you switched them to MEDICATED starter. Medication puts a strain on the digestive tract, and that tract was already weakened by the use of cracked corn. Sudden switches in feed also create create stress to the system. As my chicks mature I always gradually change the feed by mixing it with the old mix.
On one other note when you put chicks in a brooder and close it up to hold heat with out sufficient ventilation, you expose the chicks to their own CO2 and it will build in their system and is very deadly. If you found your chicks in the morning after uncovering them and they were damp, they died from CO2 poisoning. I lost Three 2 month old BRs in the extreme cold just because they piled on top of each other in there coop box for body heat. The 3 on the bottom suffocated from CO2.
There is no sense in beating yourself up over it, just monitor the chicks you have left and maybe add some more. Always start them on chick starter, provide them with grit(play sand) even on chick starter. And make sure they have adequate ventilation.
On one other note when you put chicks in a brooder and close it up to hold heat with out sufficient ventilation, you expose the chicks to their own CO2 and it will build in their system and is very deadly. If you found your chicks in the morning after uncovering them and they were damp, they died from CO2 poisoning. I lost Three 2 month old BRs in the extreme cold just because they piled on top of each other in there coop box for body heat. The 3 on the bottom suffocated from CO2.
There is no sense in beating yourself up over it, just monitor the chicks you have left and maybe add some more. Always start them on chick starter, provide them with grit(play sand) even on chick starter. And make sure they have adequate ventilation.
