Minecraft wiki entry for Experience_farming, associated text: Chickens can also be automatically hatched into an enclosure for convenient slaughtering, but they give much less experience than hostile mobs, and increasing the numbers to compensate can threaten major lag. Smelting or selling the meat provides some extra experience; it's normally about 15% of the kills, but Looting can push that up to 40%. The feathers can also be sold.