I have a coop that is 6' by 12'. In the coop I have their roosting limbs, nesting boxes and a water bowl. I do have hay covering the ground, which is dirt. In the run is dirt also. I really didn't know about the DLM until now. The main reason why I'm just reading about it is because I started with 5 hens and 1 rooster and I have lost 2 chickens in 5 months and I think my black production "Glenda" has that Mareks, which my other two that died had it too. I know that this disease is untreatable and its airborne, however out of the first two I lost couple months apart why now is Glenda catching it? My breeder told me it may be the way I'm cleaning my coop. I'm not sure if I agree because I try not to move any hay or anything that has dust that can be breathed in by my chickens. If Glenda dies than I will be down to Delaware, Chenoa and Chimi (my rooster)...2 hens out of five in less than 6 months. This is so frustrating! I love my chickens so dearly and would love to get more but if this continues to happen than I don't want to go through this pain every couple months. I've been crying my eyes out...it hurts the worst the most because they are such innocent creatures. They would probably still be alive if I just left them with the breeder. Advice anyone please help!!!!!!!!!