In 1.8 you can't give mutton to wolves like you can with other meats. I'm not sure if this intended, but it doesn't make sense for it to not work. This also affects all versions above (and including) 14w27a, only those were not on the versions list.
(If this is a duplicate, I did search for this but couldn't find it.)
Not true. I could feed my dogs mutton and all other meats.