Broodys chicks developed chest crackle

[tacothechicken]

Hey guys! So I let two of my girls hatch a total of 7 chicks a week back. Since then we've had either muggy weather rainfall or the rare sunny 75°F day. They lost one chick two days ago I the night to what I originally expected was chill( there was a rainstorm.) But today I took a chick to clear up a poopy butt only to here that distinct crackle when it yelled for mom I proceeded to scoop each one up to find all but one chick had the same crackle. I put them whith one of the broodys in the shop and a hot spot of 100° F in there cage in case she couldnt cover all 5. I gave them some probiotics vitamins and electrolites. Should I just leave them inside due to risk factor once they recover? They all eat and drink and sound off just fine but they have a crackle when they loudly vocalize. What else can I do? Ive never had such tiny babies whith this issue as usually my girls brood late summer. But this year they started. Suuuuper early.

 

[Wyorp Rock]

I'm not sure if I would provide the additional heat source, especially at 100F. They are over a week old, so 85-90F would be sufficient. A broody really "should" keep them warm.

Crackling can be from a number of things - poor ventilation, excess ammonia from feces, dusty conditions, mold, respiratory disease and the list goes on.
Does your flock have a history of respiratory disease?

Personally I would leave them housed where they were originally unless it's not secure or protected from the elements and see how it goes.

 

[tacothechicken]

No history of respiratory, but moms have been keeping them in the main coop whith the flock and we have much dust I clean the coop regularly and its straw bedding so it generally minimal dust from that in comparison to shavings or some such. Ive not seen any signs of mold or anything like that. :/ I assume though it was caused by shacking up in the main coop whith the adult birds droppings, plus rain may have caused issues. Our coop is protected but it does get chill due to being a walk in design at night so I may set up a larger area and let them hang out in the workshop till they feather out a little more and set up some more wind blockage in the main coop.