I suppose the worst I've seen, or the most disgusting for me has to be either on of two things.
One, scat research.
Two, I once saw a movie of dead animals being placed into an industrial grinder. Which is basically two rows of serrated wheels placed next to each other, moving in alternate directions.
And once the animal was placed on it, one wheel would get a grip of the skin and pull it down, where another on the opposite side with grab it and force it the other way, and this would continue until the skin was ripped appart and all the insides.
It wasn't the most gruesome thing I've seen, or the goriest, in fact, there was no blood, just some internal liquids, which may have splashed the cameras at times.
I don't know what it was that disgusted me out of it, it just did.
At the same time, though, I was slightly impressed at it's efficiency at breaking down things like bones, though.
