Minecraft wiki entry for ED, associated text: Entity data
Additional fields for mobs that can breed[show]
Tags common to all entities[show]
Tags common to all mobs[show]
 EggLayTime: Number of ticks until the chicken lays its egg. Laying occurs at 0 and this timer gets reset to a new random value between 6000 and 12000.
 IsChickenJockey: 1 or 0 (true/false) - Whether or not the chicken is a jockey for a baby zombie. If true, the chicken can naturally despawn, drops 10 experience upon death instead of 1-3 and cannot lay eggs. Baby zombies can still control a ridden chicken even if this is set false.