5 month old Dominique pullet with labored breathing

[easttxchick]

I just went out to give my birds some carrots and heard my 5 month old Dominique pullet, Cleo, seemingly struggling to breath. Her breathing sounds almost like a wheeze and the more stressed she gets, the louder and harder her breathing(for instance, when I picked her up and brought her into a hospital cage.)
She eats Flock Raiser with access to grit and oyster shell, free ranges except in inclement weather, pine shavings and pine pellets in the coop, ventilation is adequate, crop feels normal, abdomen feels OK, eating OK, comb and waddles are good and pink looking(no paleness as of yet)unsure of poo as I just brought her in. I was out with them this morning and all seemed OK with everyone.
Also, probably totally unrelated, I am currently treating the flock with Corid.
I also heard her sneeze once(of course when she shook, I could tell she had just dust bathed). Everyone else seems OK.
Just ran out to check on her and she was eating and clucking as normal, but just has that really harsh, wheezing breathing(almost sounds squeaky).
I am a veritable chicken pharmacy and have all kinds of antibiotics(soluble and injectable).
Also, she was vaccinated against Mareks.
Any ideas would be appreciated.

ETA: Noticed her tail drooping to one side a bit.

 

[chickenzoo]

Listen to her lungs right under her wings to see if she is actually wheezing in her chest, inspect her nares and sinuses to see if anything is stuck or clogged up, check inside her mouth for sores, swollen areas, discoloration, puss etc.... Could be a sinus infection or respiratory illness, so I'd give her a shot of Tylan 50.

 

[speckledhen]

Could be several things, even something stuck in her windpipe. Had that happen with a hen recently. Sounded like air escaping a balloon slowly. Also, is her heart racing? One of my Delaware pullets two years ago died suddenly of some sort of heart defect. Found her breathing open mouthed with her heart racing a mile a minute. She was gone the next day. She was about to lay her first egg and her heart couldn't take it.

 

[easttxchick]

Speckledhen, her heart beat seemed really rapid to me(as much as I know about chicken heart beats).
Chickenzoo Lungs sounded OK, nose and mouth clear.
She is eating and drinking fine still at this point.
Her breathing has quieted back to normal and seems to only get labored, wheezy, etc. if she gets excited, scared or nervous.
At this point, I am really doing nothing because I have no idea what I have here-just have her in a warm hospital cage with food and water. Not administering any meds yet.
Thanks so much for responding-I really appreciate the input.

 

[laceynoelle]

perhaps a respitory infection or something? I'll admit im not the moste xperienced here, but i had a chick doing the same thing as Cleo. thats what i guessed it was at the time, anyway. I just seperated her and made sure she had plenty to eat and drink, and i put soe pedialite in her water. Shes fine now. I hope your girl gets better.

 

[easttxchick]

Thanks laceynoelle.
Well, she was right as rain this morning, she is now back out with the others running around like a maniac. I understand it could be heart related and I may just suddenly lose her, but if that is the case, I want her to be happy out with the other birds. Just keeping an eye on her for now.
Thanks for the advice.