This afternoon, I found my Rode Island red dead. No sign of injury., and no sign of her being sick. She was very friendly and I could pick her up and pet her anytime. When I lift her up to check her well all over, a pale yellowish orangy liquid kept coming out of her break. I had never heard of sour crop, but after reading about it, I'm wondering if that was the problem. Is it contagious between chickens?