If you should ever put down or lose another chicken, it would be good to keep the body cold, and have your state vet do a necropsy. They look for MG and IB among other things. If chicks that were brought in came from a breeder, then there could have been a disease passed onto your flock. Hopefully, they will get over the illness and back to good health. You will find the 3 labs in Alabama here for necropsies in order to get more info:
https://www.metzerfarms.com/poultry...l4rPyP4Uc700UGDlSgRg8wzM0oJJdR-XLFn3O3TPZ2j8Z
https://www.metzerfarms.com/poultry...l4rPyP4Uc700UGDlSgRg8wzM0oJJdR-XLFn3O3TPZ2j8Z
