My 6 year old Serama hen's comb has slowly atrophied and died over the last 4-5 months, and although you're going to want to think it, it is absolutely not due to frostbite. This started in sweltering S. Georgia summer. When we have had a couple of cold spells at 32 degrees overnight (so not super cold) she has been protected in a coop with heat lamp so has not been exposed to freezing temperatures. It started as a small black mark on one of the "fingers" of her comb. I thought it was from a rooster/mating but it didn't heal and the blackening/shriveling has kept progressing until the point you see in pictures attached today. She was eating/drinking normally, but hasn't been laying much for a while (but hey, she's six). I noticed today she seemed a little listless, and that she had a lot of white dried urine poops down her backside which I haven't seen before. I washed her up for the pictures, but she still has that heavy urea/ammonia smell. Her keel bone is also more prominent now and her face not so red, wattles are looking a little dried out too. I have tried multiple types of treatments over the months, including checking & dusting for mites, antibiotics, topical treatments on the comb, etc and nothing has helped. Does anyone have ideas NOT relating to cold temperatures? Could this be a fungus, yeast, parasite or other health problem? The urea makes me wonder if her kidneys/liver are having a rough time.