I bought 26 chicks from E-Foul (Welsummers, Speckled Sussex, Austrolops and Ameraucanas), one male in the bunch. At about 3 weeks, 7 have what looks like Marek's: they can barely or not at all walk, and one has its head twisted down. They have only been in my garage and there have never been chickens here (the nearest ones are 2 properties away). One has already died. Could this be Merek's when they are this young?