I received my chicks last week, & they have been going great since then. However, 5 arrived with no feathers on their necks but seemed normal. Last night, all was good, but this morning, one was dragging her right leg. She could move it at all the joints & her toes were fine. It didn't seem paralyzed, just not working right. I segregated her with another chick for company to keep her from getting stepped on. She was eating & drinking but slept A LOT. This evening, she had died. Now another chick (not the one that was with her) is showing the same signs. They are building a new barn close to the coop where the brooder is & there has been a lot of noise. Also, 2 days ago, the construction crew cut power to the coop without telling anyone. When I went to do my check, the temperature had dropped to 55 degrees!! This is my first ever experience with chickens & was wondering if the problems I'm seeing could be from stress or a disaster looming for the flock. I have 13 Orpingtons & 10 Wyandottes. Thank you for any & all information.