2 mishanyot! 1 - A list of injuries or damage that render birds to be treyfot -- including a weasel that hits the bird on its head. With an apparent 24-hour testing ground to see if the animal will recover, at which point, it will be considered kosher. Also, how much of the bird would turn green in the internal organs if it were scorched for it to be a treyfa? Plus, the story of Rabbi Yehoshua ben Levi's bird that was scorched in a fire, and a color change from red to green (or green to red) being a problem.