I have a swedish flower roo apprx. 1 1/2 yrs he has been clumsy then went lame. I put him on vit b and he is now walking still clumsy but very active and eats well. I read some other posts and I am worried about mareks, he is with the rest of my chicks and has been. He has been clumsy since he was 5 mos. old and is now over a yr. Does it sound like mareks going on that long? He became lame 2wks ago it took a week of vit b to show good improvement.