I have a mixed flock of hatchery hens which I had vacinnated, chickens I purchased from individuals & those I hatched. This summer a young hen looked like she developed a leg problem and was unable to walk. I kept her inside the house and cared for her like that for about 3 months when I realized she wouldn't get better and I culled her. Two weeks ago her mother sudenly started the same thing. Her left leg sticking out front. She is 2 years old and eating like a horse so I really thought she injured her leg jumping down from something. Today she started gasping for air. This all seems to me like classic signs of Marek's but I didn't think a 2 year old hen could get it. If... and IF she has it is there any way to prevent it from spreading like wildfire? I'm scared to bits.