I have a scrawny rooster just under 18 weeks of age that I am attempting to diagnose. My goal is to keep the rest of my backyard flock healthy and safe, as I am getting ready to have the roosters processed. I live in a subdivision in a city. I do not know any livestock vets and I do not know any chicken folks to help me. I wanted to support local business and I also specifically wanted Lavender Orpingtons, so in the beginning of July I went to a local Michigan hatchery to pick up some babies. All were plump and healthy, seemingly. Along with the 6 Orpington chicks, I also got 8 silver spangled hamburg bantams. (I lost all of the bantams, but I blame that on myself for not putting a draft shield, even though there was no draft in the garage.) Fast forward several weeks and it becomes obvious that I have 5 hens and 1 rooster. Everything seems normal and good, just a bizarre hen in the group was assertive. A month ago, I begin observing conformation problems in the assertive hen. Her comb and wattles are larger and more red than her 4 sister's, but much smaller than the rooster. I also noticed that her tail is not fluffy and held much higher than the rest, but I attributed this to genetics and poor breeding. My big boy started crowing several weeks ago. I also noticed that the weirdo, ugly hen moved and walked slightly differently than the rest. Again, I attributed this to genetics and assertive personality. Then the ugly hen began attempting to crow this week and all red flags went up. I am now observing them all constantly and reading as much as I can, but I am getting very upset that my whole flock has been exposed to Mareks. The ugly hen - that is actually a scrawny rooster - now has a noticeable limp and balance issues. When the scrawny rooster goes to scratch his head, he will slightly fall over and has to catch himself with his wing. The balance issues are only noticeable when he is standing still or moving slowly. His legs will slightly shake and he will lean to one side, but only slightly. When he is running about, he has an odd run/hop. He is eating and drinking just fine. He does not have any weird twitches or neck issues, everything seems to be subtle. My healthy rooster is twice the width and size of the scrawny rooster. In fact, everyone seems to be healthy and fine except this odd ball. The man I purchased these birds from is not friendly and very defensive. When I purchased the chicks stored in his building, it seemed clean and nothing was blatantly dirty or out of place. I did not know at the time about bio-security and he welcomed the public into the barn to look at and handle chicks they wanted to purchase. He was friendly when I was purchasing the babies, but when I called with questions and concerns Mr. Hyde popped out. I have been reading about Mareks and Coccidiosis and I cannot determine what to do, how to diagnose, or how to proceed. Have I exposed my flock and property to a bad virus? Any help would be greatly appreciated.