My flock of six chickens were locked up overnight and the only things in their coop where they sleep are shavings and a heater. They were let out and no one seemed to notice anything happened. That means it either happened over night or very first thing when they were let out. Some people thought the feeder was a problem but not all of them got the cuts. Were they attacking each other? The only reason I doubt that is because the cut on the beaks is the same on all four chickens who got injured. What happened and what should I do?