I"m a brand new chickie mama. I bought an assorted Bantam variety at Tractor Supply about 3 weeks ago. I am not really sure how old they were when we bought them. They are half feathered and half yellow fuzz (SO CUTE). I am in Pittsburgh, PA. We are dog sitting for 10 days. Tonight's temperature should get down to 55. Can I leave them outside in the predator-proof coop with no heat in these temperatures or is it still too early? I"m worried the dog will try and eat the chickies in our brooder overnight.