I had someone suggest to me on here about cod liver oil for Vitamin D this winter being that we cannot rig up a light for the girls. I have been reading what I can find online but there's not a lot of info. about feeding it to chickens. I'd like to possibly give it a try. Has anyone else had any experience with this? Where do you buy it? And is there a particular brand that's better as I read the quality of the brands makes a big difference? Thanks for any help!