This website is an eye opener - learning new stuff everyday
What a Fox Eats | The Complete Guide - All Things Foxes
Although...
A friend of mine's dog ate a raisin the other week and she took him in to get him to vomit.
She had a dog trainer around later and he said he wouldn't have worried about it so maybe it's a case of Chinese whispers in the veterinary community, after all a lot of the medical profession don't seem to know anything about health - they just like prescribing drugs - in the case of animals it's metacam for anything and everything.
It's very difficult to get accurate information these days I find.