i had 12 rir,19 weeks old. about 4 weeks ago i bought 12 older birds at a swap meet. this will not happen again. my problem is after about a week some birds started rattling and haveing runny beaks. i have lost 4 birds since. they had tetra cyclene for 10 days ,this stopped friday.is this as bad as i feel it is??? should i think about destroying these birds ??? these are my egg hens thanks for the help.