I have 9 silkie chickens in New York state. One of my roosters, who is about 5 years old, has been acting off for the last few days. I have been monitoring him but he has been eating, drinking, and getting along with the others. He has been walking slower and hasn't been crowing. I have just confirmed they were not vaccinated (Tractor Supply) but regularly get vitamins and VetRx poultry aid, as well as fresh fruit/vegetables and time outside (they live in my garage). Today he is lying in the corner with his face down and only picked up for a second when I touched him but never stood up. I do have one other rooster but I have been unable to identify any injuries on either of them. Everyone else in the flock is acting normal, except one that has had an on/off eye infection for 2 years that is regularly treated that has never spread. Any help at all would be appreciated as I don't know how to help him and I'm quite distraught.