Could you provide a few more details? What are all of her symptoms? Is one leg or both paralyzed, or does she have curled under toes, or walking on her hocks? Do her eyes appear normal? Is it hot out where she might be dehydrated or suffering heat stroke? Is she eating or drinking? Is she gasping for air? Have you added any new members to your flock recently who might have been a carrier for Mareks? There can be a number of conditions that may resemble Mareks disease. It can be confirmed with a necropsy by the state vet if you lose her. RAL lab does a home blood test if you are interested. I really hope that it is not MD, and that you can save her. I would start some vitamin B complex 1/4 tablet daily in case of a riboflavin deficiency.