I have 9 girls they are only 14 weeks old and I don't know which ones are having these issues or making the noise. I've been trying to find out but anyways I've been finding an almost black diarrhea in the coop. Is this something I should be really concerned about? Also today this is the first time I've heard it but I heard a funny noise coming from one of them by time I went over it stopped so I don't know who it was. It sounded kind of cough like but not really or I don't know maybe a noise someone or something would make if they were trying to clear their throat. What should I do about all of this? And should I be really worried?