This is what I found by Googling - not sure how many the dog would need to be affected though, how many is a small amount I don't feed my dogs human food...for the simple reason all 3 would like some of what I've got and I would not get any peace at meal or snack times, so the rules are 'It's mine - go lie down'
Grapes and Raisins
What could seem more harmless than grapes? They're a perfect natural snack for children, and some dogs love them. Yet even small amounts can cause lethargy, depression, and kidney failure. Vomiting and hyperactivity are early signs of grape poisoning.
CREDIT: istockphoto