I have had 2 hens die on me in the past 3 months with the same symptoms......standing on roost ``trying to crow`` like , neck stuck way out ???gasping??? and then 30 min later dead???? I have been giving them apple cider vinager in thier water, giving them fruits and veggies also yoguart and soured milk...I am trying not to give them medication..... so I am I at the point I need to start give antibiotics? my other hens seem fine but my other 2 seemed ok too but I was wrong...... oh and it wasnt the croop. If I do start them on antibiotics (Tetracycline) how long do I have to wait to eat thier eggs and how long till I can incubate them?