I have a flock of about 28 hens. I am loosing one about every week. Up to 6 in the last month and a half, and about 4 over the previous 3 months. None of the chickens have any signs of illness whatsoever. They all suddenly stopped laying around the end of July. My 2 roosters (about 8-10 months old) suddenly stopped crowing at the same time, and haven't made a peep since. When I lost the first one suddenly, I found mites on her during the inspection, and after a closer look at everyone else, found that one of my roosters, which I brought home from a feed store about a month before was LADEN with them. (I checked him over well before I brought him home and never saw any, but I'm thinking I missed them.) So we went through 2 very thorough (one week apart) treatments of Sevin, on every bird, and the entire coop. Waited to see the eggs return, and nothing. Wormed them, twice, according to instructions. Still nothing, and still dying mysteriously. I have researched all I can find, and nothing matches. They are all visibly healthy and well fed. I would love input from anyone who may know what is up with my birds. I can't believe this is just a case of Sudden death syndrome, as its happening too frequently. AGES: Most are 10 months old and had begun laying frequently at 5-6 months old. About 8 are 3 years old. All heavy/full size breeds. FEED: Scratch and Peck Organic 16% layer and Organic, soy free, whole grain scratch. Free fed Oyster shell (Also in feed) Mostly organic table scraps, daily. Probiotic water supplement in addition to plain yogurt as a treat about once a month. HOUSING: Completely free range until last March, now in an enclosed 20x30' run, (due to stinking Bald Eagles) and huge coop, free ranging occasionally. SYMPTOMS: No breathing issues, no egg binding, crops are fine, good weights, They've been treated for mites, and worms. No neurological symptoms before death, no ruffled feathers, some lethargy noticed in 2, they were isolated, and well cared for, but did not recover. Most birds have been found dead first thing in the morning, under the roost. A couple in the run. THE OTHER THING: About 2 years ago, while living at another home, I brought home 2 non-hatchery lavender Ameraucanas from a local breeder. One died of apparent neurological disfunction, but survived in this state for some time, inside, with care, unable to walk or stand, before dying. She was sent for necropsy, which came back positive for Mareks. I lost 2 more birds with the same kind of symptoms, but the rest survived. About a year later, I had a Mama hatch out chicks, all which survived, and we moved, bringing our chickens along. I purchased 30 chicks last spring, all which were vaccinated for Mareks. I kept them in isolation for as long as possible, before introducing them to the older flock, to help their chances of survival, and combined flocks at about 3 1/2 months of age. They were all healthy and happy until about 7 to 8 months of age, and around the same time I brought a seemingly healthy rooster home. If you have ANY input at all, I would be grateful for a response. I am now dreading going to feed in the morning, wondering who I might find dead next.