I am having a similar issue as the OP. 31 chicks from Mt Healthy hatchery arrived on 4/4. One was not doing well the day of arrival and ended up dying. I had another die yesterday and now one that is very weak and falling to the side today. The one I found dead yesterday was a shock. The one that seems like it will die today is displaying the same symptoms as the one that died on Friday. The chicks are in an 8x4 brooder in the chicken coop. I have three heat lamps up but have turned the middle one off as needed as well as raising/lowering the lamps as needed. The chicks were on electrolyte water for the first three days. I switched them over to plain water yesterday, but after seeing this last chick, I have replaced that with nutridrench water. The chick that is weak, I have a couple of drops of nutridrench directly and also tried to feed some egg yolk. The only yolk she got is from reflex if swallowing when I dipped her beak in he yolk. My chicks are currently in puppy pads. I lay clean pads over the old as needed. When they are a week old, I switch them to pine shavings. They are meat birds so I started them off with Purina game bird feed. Did the same with the batch I raised last year and all 30 survived-though it was late April when they arrived, and they came from Meyer Hatchery instead of Mt Healthy. I have been seeing runny droppings so I don’t know if the temperature fluctuating is the cause. Next year, I am going back to having the birds delivered at the end of April. I just tried a little earlier this year because the birds seemed very hot by the time they reached processing age. However, last night and tonight, the low will be 27. Then the temp jumps to 45-50 degrees during the day. I have found it very hard to regulate the temp and am worried it is the cause.