X4 @Shadrach
In all honesty keeping a clean, well ventilated coop & plenty of exercise space would be my best preventative advice. I deep litter my run but clean out my coop every few days, depending on weather & amount of poop. I do use ACV in 1 water tub out of 3 because my girls like it. Nothing likes living in a grubby unhygienic space ~ not even pigs~ so I do my best to keep things as clean as possible ~ not always easy with chickens but they do appreciate it.
In all honesty keeping a clean, well ventilated coop & plenty of exercise space would be my best preventative advice. I deep litter my run but clean out my coop every few days, depending on weather & amount of poop. I do use ACV in 1 water tub out of 3 because my girls like it. Nothing likes living in a grubby unhygienic space ~ not even pigs~ so I do my best to keep things as clean as possible ~ not always easy with chickens but they do appreciate it.