I have lost two chicks a week apart. Both were two weeks old and seemed happy and healthy in the morning and were dead before bedtime. They fluffed out, were sleepy, and wouldn't eat or drink. One had a seizure of sorts before it died and then had blood in its poop. The chicks are eating Nutrena Medicated which says it protects from Coccis and to not use Corid (generic name?) in addition to the food. Could the chicks still have have died from Coccis? Even while on the medicated food? Should I go to non medicated food and treat the remaining chicks with Corid or just assume it was something else that killed them?