I have chicks dying they're from 1wk to 2 months old, they get very lethargic & sleepy acting then the next day or 2 they die I know it's no pasty butt but I'm not sure otherwise I've already lost 10 & I don't wanna lose anymore, I haven't had any trouble with my hens but they're outside is it safe to give them iodine in their water or what should I do