I have 19-week old pullets. Five of them are Brown Leghorns and 3 of those developed bright red combs early - a couple of weeks now at least. Today, I noticed that the pullet that had the brightest red comb and face has a black tip at the back of her comb and the comb is faded red toward the back. I also think he face has faded. She and all the other birds are eating very well, free-ranging for part of each day, and act completely normal. One of my leghorns has always been very pale in the face area, with no comb development and she is notably small. That one was a bit lethargic until I gave them a 5-day round of Corid a couple weeks ago, but now she is active and eating well, but still pale. I notice a fleck of black on the comb of another leghorn that is just starting to develop a red comb, and my biggest, brightest New Hampshire rooster had a fleck of black on his beautiful comb. I wouldn't have worried about the black on this leghorn, except that I notice her color is somewhat faded compared to a week ago. I will have trouble believing it is diet. They are all still on a good chick starter, get a few protein treats and have good ground to free-range on.