I just had this same problem! I was told that it usually indicates a sinus or ear problem, so I gave them Duramycin 10 and the chick that was really not looking well is looking much better now and everyone is ok. If you need help with dosing....it's 1/4 teaspoon to one gallon, I had a real hard time figuring it out and got an answer on hear for that also. GOOD LUCK!