Hi folks. Haven't posted for a long time. I had an experience I wanted to share. I ordered some more Swedes from Greenfire that came in April of this year. One of the chicks came down with what looked like Marek's at about four weeks of age. This happened before in my last order with a hen I had named Sandy, and I ended up putting her down as she never got better. Splayed legs, toes curled, couldn't walk. I did have Sandy's blood tested and to my surprise, whatever it was was NOT Marek's, although it looked just like Marek's. Also had three others in that first batch with slightly crooked toes.
Well, this time from the first I saw the symptoms I put infant vitamins (poly-vi-sol w/out added iron) in the water and gave the chick snacks of foods I knew to have B-12 (hamburger, esp). Well, this hen got better! She's now running around with everyone else, no crooked toes. I began putting the infant vitamins in everyone's water, and have been ever since. I had 16 chicks, plus three more that a broody hen hatched to make a total of 19, and NOT ONE CROOKED TOE.
Long story short, I think these SFHs need B-12, or niacin, or some other vitamin they don't get enough of in their food. I saw an article on the web about curly-toe paralysis. It was a study about Leghorns with this issue, and them getting better on the whole if the vitamins were given early enough. Of course I can't find the article now. Anyway, my advice would be start those vitamins right away from the moment you receive, or hatch, the chicks. I put one and a half to two droppers-full in the gallon size water dispenser.
I know this is anecdotal but I really think vitamin deficiency may be the cause of the curled toes.