I'm not going to go off on a massive rant here but just because this kind of thing usually doesn't show up on animal planet or discovery channel doesn't mean it doesn't happen thousands of times a day in the wild. I've seen footage of a buffalo having it's rear end ripped off by lions before it died and seen hyenas do the same thing. This is the sort of thing Darwin saw that made him understand that the world isn't all fuzzy and perfect like he imagined and led him to eventually write the origin of species.
No it isn't very nice to watch but it is nature unedited and it is happening all over the world 24 hours a day.