Hello all, Today I noticed one of my Cream Legbars is lethargic and has a very bad looking, dark and droopy comb. She also has runny, whitish smelly diarrhea. She lies still and is very lethargic. All other hens look and act normal. The sick hen is one year old. I have isolated her from the others. She was vaccinated against Marek's disease at the hatchery. What can I do? Please help, I have read a lot but have so far had very healthy hens and chicks so do not know much about diseases. Thank you in advance for any suggestions.