My Chikens share thier food with any bird thats passing so I have given them my mixed bird food as I cannot see it doing harm, funny thing is, I have some hubbards, I give them growers pellets in the morning then let them out for a roam around 2 and as soon as I open thier run there are 2 ex batts ready to run in to take a look at thier food, almost like people queing at a sale, the other funny thing is the hubbards raom a little but then sit down next to thier run until they return themselves to bed!!!!