You need to get some brewers yeast(NOT bakers yeast) found at the feedstores or some niacin tablets(non flush) can find them in the vitamin supplement section of most pharmacies. Sprinkle brewers yeast over their food or get the tablets and crush them and sprinkle on the food or in the water. It sounds like they have a niacin difficiency. Keep them on it until atleast 3 mos old. Also make sure they are getting plenty of greens.
Brewers yeast measurements is 1cup brewers yeast to 5lbs of feed
Tablets measurements is 100mg( 1 tablet) crushed into 1 gallon of water or over food.
