You can keep them alive on it for a while in an emergency, but it doesn't include everything they need. Chickens, like most birds, need high levels of protein in their diets. Wild birds can fill in this need with insects, worms, spiders, etc. that domestic chickens may not have access to. In addition, birds of all types need lots of Vitamin D, which wild birds get from constant sun exposure...chickens that have the option of staying inside a coop and/or have a shady yard may not get all that they need. Chicken feed like what you will find in a feed store is a pellet that includes the fiber and nutrients they would get from the seed, as well as the protein they would get from bugs if they were free-ranging and added vitamins so they can thrive in domestic conditions.