I doubt it too - it'll probably love it & be back tomorrow night for some more! (Lucky fox - ours round here have to be content with murdering our chickens!)
I wouldn't think so. They seem to eat pretty much anything. I often throw out food scraps for them for our regular night-time visiors, including large chop bones and fish skin and everything is scoffed up.
Hope you don't give them cooked bones Wendys, they will eat them because the don't know any better but they can do them a lot of harm, they splinter and get stuck in their intestines and stomach, hope you don't mind me telling you this I feed foxes every night and have found out what is good and bad for them.