I have 18 hens 15 of which are about to be two years old and three that are about 15 months. The flock make up is 5 Australorps, 4 Golden Sex Links, 4 Black Sex Links, 4 Rhode Island Reds and one Barred Rock. I came across BYC via friends with chickens and various internet searches. My partner and I operate a B&B and when we got tired of buying psuedo "free range/organic eggs for $5 a dozen we decided to try to raise our own. So far so good, except this summer I had an infestation of Northern Fowl mites that I am still dealing with in terms of the skin rashes. Yesterday, one of my Black Sex Links showed signs of distress. Her symptoms includes a gasping wheezing gesture and a rumbling in her tummy. I am wondering if this is Sour Crop. That is the issue that prompted me to sign up. I look forward to any help and advice I can get.