I have 4 hens, 2 americaunas, 1 small white one and a small buff one with feathered feet. (The last two were given to me and I don't know exactly what they are but they all lay distinct eggs so I know which egg came from each hen.) Anyway, recently about 50% of the time I use an egg from the little buff hen the yolk is darker than usual and it is also rather thickened and gloppy (for lack of a better term!). I have been throwing them out when I find them but I was wondering if anyone knew what was going on. They smell fine but don't look great. It doesn't matter what age it is, the egg from today was the same way. Sometimes the egg even looks strange without cracking it open and I just throw them away. Any ideas? No rooster, she has not been sick, diet hasn't changed - layer crumbles and fresh veggies and fruits, whole wheat bread.