Sad to say our old Henrietta , 7 yr old .. has Salpingitis .. walking like a penguin.. but still eating. Another hen also has developed symptoms. we plan on putting them both down.. will this spread thru the entire coop ? DO we have to cull the other 6 hens & 2 roosters ?? one chick just hatched one chick.. is it in danger ? ? HELP .. hate to kill all of them ! Are there shots we should be giving the healthy hens. do you vaccinate on a regular basis or add vitamins to their water as adult ckens ?