No such thing as animal rights

Rights are based on moral agency, not the ability to feel suffering. Humans are assumed to be generally morally accountable for their actions because we are assumed to be able to make moral distinctions and choose, or not choose, to act according to them.

Although one might argue that such a definition excludes babies and the developmentally disabled, one can simply point out that, in fact, babies are the responsibility of adults precisely because they are considered to not have fully developed the ability to apply the type of considerations that moral agency entails. Likewise, someone who is developmentally disabled to the point where they can't be held responsible for their actions is generally placed under someone else's care or made a ward of the state. However, because they are part of a species that generally has that ability, they still retain rights that aren't applicable to non-humans.

This is also consistent with the concept of legal insanity, at least as applied in the Anglo-American legal tradition, where the test is based on awareness of one's actions AND the ability to make moral distinctions.

Apply this test--Are you prepared to think in terms of good and evil animals? I rather doubt there is one case of an animal acting viciously were the humans responsible for it weren't considered to be blameworthy.