One of my Hens had a cough about 2 month ago. I treated everyone with Oxytetracycline HCl in their water for 7 days. She was better in 24 hours. This morning she is sneezing. 12 hens are out all day free and come in at night. Should I start the antiobiotic again? Love my ladies. Really hook on all your good information and just the joy shared.