Small green budgie with an abdominal mass. I don't know the whole story. It was just handed to me and the doctor said "can you take care of this please." (Upon a post-mortum exam it turned out to have a huge splenic mass.)
I didn't actually do the injection but I instructed an eager intern on how to euthanize a Cooper's hawk with a degloved wing.
There was a bird I wanted to put out of its misery today but the owners refused. It had been attacked by a dog a month ago and its skull was visible, its eye was totally necrosed and oozing and it was completely emaciated. I'm not even sure why they brought it in since they refused to treat it.