I've been feeding fermented feed for 5 months...I call it chicken crack. They seriously LOVE it! Here is what I do. I use a large mayonaise tub (the Sam's club big size--I thinks its a gallon size? I'm not home, so I can't run and check), I fill it half way with hot water, 1/2 cup of apple cider vinegar and then I put 6 solo cups (yes, very accurate measurement lol) of layer feed. Cap it and leave it in my sink overnight. Sometimes it will overflow the first night. Anyway, on the second day, I can smell it, smells just like my wine when it is fermenting in the primary bucket. On day three, its perfect. I have 10 hens, they eat half of a container every day. I have 2 going at all times. They don't waste a bit of it. I put it out at 6 am and by night its pecked clean. I also have a feeder with dry feed, but I only put a few cups in a week. They really like the fermented much better.
they also are reaping the benefits of all our garden scraps right now. I'm sure in the winter they will be eating a lot more-- the garden supplements a lot.
Hope that helps.