I'll use the list the site suggests to start... 1) What type of bird , age and weight...........SILVERLACED WYANDOTTE, 10 MONTHS, NOT SURE ON WEIGHT BUT MAYBE 6-8 LBS? 2) What is the behavior, exactly...........NONE THAT I SAW. SHE APPEARED HEALTHY BUT WAS DEAD WHEN I GOT HOME THIS EVENING 3) Is there any bleeding, injury, broken bones or other sign of trauma............NO 4) What happened, if anything that you know of, that may have caused the situation......NO CLUE. TEMP IS 26 F AND SHE WAS NOT IN THE COOP. 5) What has the bird been eating and drinking, if at all. I JUST INCREASED THE FOOD AVAILABLE ADDING BIRD SEED WITH BLACK OIL SUNFLOWER SEEDS AND SCRATCH TO GO WITH THE PELLETS/CRUMBLES THEY HAD BEEN EATING. THEY ALSO GET EGGS/TOMATOES/AND GREENS. 6) How does the poop look? Normal? Bloody? Runny? etc...............NORMAL 10) Describe the housing/bedding in use........8X4 PLYWOOD COOP WITH HEAT LAMP AND PINE SHAVING ON FLOOR WITH A ROOST AND NESTING BOX. I'm really at a loss here. She had only recently died when I found her as her body was still warm. She had pushed herself in between the house and a trash can. There are no signs of injuries whatsoever. The only changes of note are the increased food available...maybe the other seed in the bird seed mix other than the black oil sunflower seeds is a no-no? The other significant change was the application of nitrofurazone which is a topical antibacterial for dogs/cats/horses. The lady at the feed store said she uses it to stop chickens from picking out each others feathers. Interestingly though, the chicken that died was barely being pecked by the chicken who was plucking, so I applied less on her than all the rest, so I doubt this is the culprit. It was applied 4 days ago. She was laying right up until today. Eating, drinking, taking dirt baths, etc. No odd behavior whatsoever. The only thing I can think is she didn't go into the coop for whatever reason and froze? It was only maybe 30 degrees when she died though, and they bop around the back yard in 15 degrees and snow without a problem, so it would seem weird for this to be the case. She's not bloated or thin. I'm stumped. How would I go about finding out what killed her? Vet? If so, how much would this cost? Thanks for the help everyone. I really hate to have lost her and don't want to lose any of the other 3 birds.