I have a group of 50 chicks. A week ago we lost 2. I hoped it was an isolated incident as there was no apparent cause and everyone was healthy. 3 days ago I found one gasping for air and stretching its neck out making squeaking noises, not eating or drinking. Isolated the chick immediately and treated it with vitamins, Ivermectin, and Vet RX. Looks like a textbook case of gapeworm but these chicks have never been exposed to the ground or to other chickens that have been exposed to earthworms or other sources of the parasite. The chick passed over night and seven others have come down with the same illness. All have passed except 2 that are declining rapidly. I chick-autopsied the first victim with a q tip swabbed in its windpipe and found no evience of worms, just clear mucus.. It has been hot and humid here, heat index of 100 or worse and raining daily which could be contributing to respiratory disease. If anyone has any ideas I need help before I lose all of them.