Make certain that there is Chicken Feed in the Poultry Feeder on the floor. You
will be able to see when it is empty.you can also just take it outside,remember as long as it's not raining or snowing!
Another thing is that the game won't let you put feed in the other spaces unless there's an animal feeding from there, so be sure to check you're feeding all your animals if you have more than a few.