There's a few studies that do seem to indicate that turmeric MAY provide some cocci support in suitable doses, when mixed with feed. Chicken07 compiled information here:
viewtopic.php?f=5&t=7984943&p=345579Heaven knows what colour it might turn white chicks though

I use unmedicated crumble (Red Hen chick - not organic though) as the medication in the medicated stuff doesn't seem to be effective against my strain of cocci. I instead use Amprolium in the water at preventative doses, as appropriate.
However, I have also found that warmth, cleanliness, and space are basically the main way to prevent cocci without using drugs. Give the (hen and) chicks enough space that they're never treading in their own wet droppings, clean out their sleeping area _regularly_, and provide them with a separate "sunroom" area to sunbake without breezes, and I can raise an entire batch without medicating once, and with minimal losses (1-2 per 30, say - and they were Marans anyway!).
(And anyone who knows my ongoing cocci issues knows what sort of miracle that is!).
However, when I say space, I'm talking an orchard for at most 20 chicks. 20 x 20m sort of things. Basically, raise your chicks in a paddock with lots of shelter, greenstuff, and a portable sleeping area that can be shifted weekly to a new, clean spot, plus excellent feed support, vitamins in the water, and add in turmeric/oregano/whatever else, and I reckon you could raise chicks organically and with minimal losses.
I've been collecting ute covers and using them as the "sunrooms" for the chicks - works brilliantly. They don't tend to sleep in there at night, interestingly, but they love hanging out there during the day. I put food and water underneath and on cold, wet days, they may not move all day

. So I just shift them to a clean spot every week or so.