This afternoon I noticed my 11-month-old Buff Orpington was lethargic -- lying down in the run kind of hiding in a corner, no interest in the kitchen scraps, her comb was a little droopy, and she had some runny white poop stuck to her tail feathers (see pictures). She had no other external symptoms that I could see. My son said she was also not herself yesterday either when he went to get eggs, but that she had laid an egg either yesterday or the day before. Her breathing seemed to be ok and she was still drinking from the waterer occasionally.
Anyway, I brought her inside, checked her for a bound egg (not the problem -- but she did squirt out some runny poop during that process -- see pic). I started feeling for her crop. This being my first year with chickens I didn't really know what I was looking for, but I didn't feel anything (so I think her crop was empty?) After feeling for her crop, her breathing got faster and she seemed to lose alertness. Her breath did smell very fermented, which supposedly is a tell-tale sign of sour crop, so I thought I might try treating that. The Chicken Chick book said to give her an Epsom salt solution, which I tried to do with a little a syringe. I think I administered it too fast and it must've gone into her lungs (?) because then her breathing started to have a raspy gurgle to it. Within a few minutes she started flopping around and then stopped breathing entirely.
RIP Scruffy
Anyway, what should I have done? (other than not give that Epsom salt solution!!) Any idea what her problem might have been? My other three hens look great and are acting normally. This is the second bird I've lost to some kind of sickness in one year (the other one was 6 months ago) and I'm wondering if I'm doing something wrong!
Anyway, I brought her inside, checked her for a bound egg (not the problem -- but she did squirt out some runny poop during that process -- see pic). I started feeling for her crop. This being my first year with chickens I didn't really know what I was looking for, but I didn't feel anything (so I think her crop was empty?) After feeling for her crop, her breathing got faster and she seemed to lose alertness. Her breath did smell very fermented, which supposedly is a tell-tale sign of sour crop, so I thought I might try treating that. The Chicken Chick book said to give her an Epsom salt solution, which I tried to do with a little a syringe. I think I administered it too fast and it must've gone into her lungs (?) because then her breathing started to have a raspy gurgle to it. Within a few minutes she started flopping around and then stopped breathing entirely.

Anyway, what should I have done? (other than not give that Epsom salt solution!!) Any idea what her problem might have been? My other three hens look great and are acting normally. This is the second bird I've lost to some kind of sickness in one year (the other one was 6 months ago) and I'm wondering if I'm doing something wrong!