I just got back into raising backyard chickens and I have a couple of 5gal pails full of OLD lay pellets. They have been stored with the lids on and there is no apparent moisture The color has faded a little, but other than that, they look perfectly good. Some dry packed grains can last 4-30 yrs if they are properly stored and sealed in completely air tight containers! How long will it take chicken feed to become outdated and loose it's nutrient value?