I'm concerned with one of my young silkies. She breathes with her mouth open and closes it with each breath. Her mouth is barely you open when she does this. She has no other signs of illness and none of the other chickens she's with have this problem. It's been going on for quite a while. I tried some VetRX but that didn't do anything. Could it be genetic?
I have a Silkie with CRD issues and last Spring I had to take her to the vet to have minor nasal surgery to clear up the serious clog in the nostrils. Made no difference even with medicine because they look clogged to me again. She's my problem CRD child! Chickens will open their beaks during heatwaves too. Check your bird's nostrils against the nostrils of others to see if you can tell if there's clogging.