Hi there, I'm a first-time chick raiser with four buff orp's hatched (approx) one week ago today. Got them on Monday. Everyone seems very healthy, active, eating, drinking, etc. When i put my hand in the brooder, some of them will come over and stand in my palm. It almost feels like they are vibrating, or purring. Anyone else ever experience this? Do they have a contented "purr", or is it shivering with fright or something? seems like if they were scared of my hand, they wouldn't run over and jump on it. The heat lamp is always on and its always between 93-98°, they always seem comfy, moving closer and farther away as needed. hmm.....