I opened up the coop this morning and discovered my normally aggressive and active rooster huddling in the corner shivering. He's got a bloody comb no obvious cut or scratch. The blood seems to be coming mostly from the "crotch" between 2 tips. I brought him inside, cleaned it up, and sprayed some antiseptic on it. I gave him an inspection and nothing else seems amiss, but he won't stop shivering. It's been just barely hitting below freezing lately, so I suppose it's possible that it's frostbite, but we've had roosters with frostbite before and this seems different. Any tips? Thanks in advance.