Just as we reject racism, sexism, ageism, and heterosexism, we reject speciesism. The species of a sentient being is no more reason to deny the protection of this basic right than race, sex, age, or sexual orientation is a reason to deny membership in the human moral community to other humans.
Animals are property. There are laws that supposedly protect animal interests in being treated “humanely,” but that term is interpreted in large part to mean that we cannot impose “unnecessary” harm on animals, and that is measured by what treatment is considered as necessary within particular industries, and according to customs of use, to exploit animals. The bottom line is that animals do not have any respect-based rights in the way that humans have, because we do not regard animals as having any moral value. They have only economic value. We value their interests economically, and we ignore their interests when it is economically beneficial for us to do so. At this point in time, it makes no sense to focus on the law, because as long as we regard animals as things, as a moral matter, the laws will necessarily reflect that absence of moral value and continue to do nothing to protect animals. We need to change social and moral thinking about animals before the law is going to do anything more.