So far today, two of my 3 year old hens have torn off a decent chunk of one of their nails. Ofcourse they bled perfusely but I got the bleeding to stop. Im not sure why this is happening. I trim their nails as needed so they arent too long. It did drop to -20 (without windchill) here today compared to above 30 yesterday. Could it be a fluke or something more serious? Help!