I think it is not anthropomorphic to interpret very basic emotions to animals. If you start saying your cat can do quadratic equations, then I might start to worry. But I have seen too much joy, satisfaction, boredom and worry on the animals in my life to think that for some reason our spoken language abilities make human animals more able to experience emotional states than can the nonhuman animals, who simply cannot communicate them to us except through their body language.
"What we want to change we curse and then
pick up a tool. Bless whatever you can
with eyes and hands and tongue. If you
can't less it, get ready to make it new."
--Marge Piercy, from "The Art of Blessing the Day"