Hens dying one by one

[a74aggie]

Ok, I had a dog attack and injured a few chickens. One of them died in the coop one night shortly afterward. (Didn't notice any injury on her, but she may have been.) The others ate it before I got out there that day. Then one more died and I have had one or two die each evening since. Some have been eaten, some have not....SO....., today I am taking one that died last night to a Texas A&M Veterinary Medical Diagnostic Laboratory for analysis. I will update this thread as soon as I know something.
I have not noticed any looking sick or hurt, and have not seen any bad poop. I have been administering cordid in their water for a week, and I also administered a preventative dose a couple of months ago.
I hope they don't tell me to burn down my chicken coop....

 

[nuthatched]

What's their diet?
Ages?
Temperatures?

 

[Eggcessive]

Your other chickens ate another chicken before you got out there that day? Can you give more details? Do you normally let them outside in morning, and lock them up inside a coop by dusk? What is the coop and run like, chicken wire, 1/2 inch hardware cloth wire, or other? Is there any overcrowding? Are they eating a balanced chicken feed?

 

[a74aggie]

Your other chickens ate another chicken before you got out there that day? - I assumed it was the chickens eating them but the TAMU Vet says no. He listened to my story,looked at the dead chicken I brought and said it is most likely rats or some other predator, But he is proceeding with the testing.
Do you normally let them outside in the morning, and lock them up inside a coop by dusk? Yes, every day.
What is the coop and run like, chicken wire, 1/2 inch hardware cloth wire, or other? I have 1/2 inch hardware cloth on the walls and it turns down on the ground and runs out 16-18 inches.
Is there any overcrowding? No, I have a 12x12 coop and about 15 roosting but they get out right away in the morning. Are they eating a balanced chicken feed? Yes, and they free range during the day.