I use a vitamin supplement from TSC on occassion ....with new chicks, for birds in molt, etc. I don't think it has contains as many minerals, etc - but it does seem to help. It makes the water yellow and I think it stinks..... LOL I read similar things about Avia Charge 2000...brown water and smell. Most supplements use fish emulsion which is probably why they have the strong smell.
I was reading a chicken news letter from 1923 that stated using buttermilk mixed in with the lay mash would have similar results, more egg production etc.. I have tried this recently and it definitely helped with the egg production and the chickens seemed to love it.
i use this product,i got mine from mcmurry also.i have 3 brooder hens and give it to them 2 times a week,plus the chicks helps them alot in this rotten weather.i also use it for the layer and bantums. a little goes a long way