lost a housecat one time. It took 3 attempts and a half tank of gas, but I was finally successful.

Haven't taken but a dozen-odd 'big game' animals, but haven't lost one yet. One antelope I shot badly was a horrible thing, however. She was bedded down and I must have spooked her just as I squeezed, and the round unzipped her belly as she stood. UGLY. Ended up putting 3 more 7RM rounds in her as she ran along dragging 20 feet of intestines behind her. A bud with me finally rolled her with two .35 Whelen rounds. Not a proud moment, that.

Several years ago I lost a poorly hit doe, knew it when I heard that hollow thump that I'd gut shot her. She had come up out of a hollow and stopped for a moment before starting off again just as I shot. Trailed her across two neighbors places before I lost the trail. I'm always very careful about shot placement as I don't want that feeling again.