I have 6 two year old Red cross hens. In the last month we've went from 5-6 eggs a day to 3, sometimes 4. I realize they are probably about done laying. One of the hens I've noticed for 10 days or so is having some issues. She seems really stiff, always moving really slow. Her comb also is a little pale, not as bright red as the others. I haven't changed anything, same feed, scratch grains and free ranging a few times a week. Any ideas of what's going on with her would be appreciated.