Here's the problem with articles like this, in an effort to make a reliable article backed by scientific studies, They are trying to find written proof and documentation when there is little to none out there. They found studies that were close but certain parameters and variables were skewed to offer recommendations for Backyard keepers. Chickens have been and for some unforseeable future will be considered expendable livestock. A big expensive study will most likely not happen when it's cheaper to put a bird down with problems.
My grandma did not sit down and write a thesis when she gave ACV in her water to her chickens. She used it because her Mother used it and her Grandma used it and found results and noted differences in their birds. I use it and found less incidence of pasty butt, Faster feathering by I suppose more efficient protien assimilation as touted by Braggs. When you see your chicks picking through droppings for their spilled pellets think about the competing bacteria that's lined their stomachs with ACV (good bacteria) and the competition reducing the bad bacteria from their pickings.
I agree whole heartedly on fresh water everyday--with a 1/2 cap splash of ACV. It does not have to be Bragg's--Heinz makes some and a off label Target brand also has it with the Mother or good bacteria. I believe that bedding should also be clean...but as you know with chicks and chickens poop happens.
I use non-medicated feed--not that I'm against it if warranted--but just evidence that I have not had problems while using ACV. Cleanliness and ACV will not hurt and it may even help. I cannot give evidence that you should or I probably won't because it's time consuming ...but the internet and BYC is loaded with proponents. That may be evidence enough to put it in your routine.
