When my chickens come out of the coop in the morning, they often chase each other. One will run after another one and then they will stop and fluff up their head and neck feathers. It seems to be a game - no one pecks or chases very far. They usually just run a few feet and stop. Is it a game or a pecking order thing? The two older hens (18 and 20 weeks) do this with each other, and now the younger ones (8 weeks) are also chasing each other when they first "get up" in the morning.
It does look like "playing" doesnt it! I agree that they are stretching there legs, kind of like us stretching when we get out of bed.
Whenever mine do this it's because they're chasing a flying insect. A couple of them will suddenly take off at a run for a few yards before it either gets away or gets eaten. It's hilarious to watch.
