i have unvaxxed chickens and one got a lame foot at about 12 weeks (beginning of july). the condition lasted about 2 weeks and then got better for a few weeks. then she started flopping over every few steps, toes curled, walking on the top of her foot. another hen began to mother her. within 2-3 days that second hen began to have trouble walking. i separated the two chickens from the others and begin giving them all vitamins and electrolytes. the second hen quickly deteriorated, by the third day she couldn't get up. i put her down and figured i would have to do the same with the original chicken, but held out hoping she would recover for a 2nd time. she did. i know once a bird has marek's they always have it, but is it possible to "lose" symptoms or signs of marek's. was this a vitamin deficiency? i still have her separated from my other chickens, though i'm assuming they would all have marek's if she has it. the two chickens who showed symptoms (the one i put down and the one who "recovered") were/are the smallest and the only 2 who wouldn't get out of the run to go forage through the yard (though the recovered one is being a normal chicken now and running around the yard when the other chickens are in the run).