A question often pondered by ethicists is whether or not pacifism should extend to the animal kingdom. Since animals are living, breathing organisms, is it right for us to slaughter billions of animals a year to feed humans who do not actually need their meat to survive?
Many individuals have become vegetarian and even vegan in pacifistic protest of killing animals. Many more have stopped buying leather and furs. Currently, 3.2% of the US population, around 7.3 million adults, are currently vegetarian, and yet another 5.2% (11.9 million) are interested in starting a vegetarian diet (http://www.raw-food-health.net/NumberOfVegetarians.html). On the other hand, India has around 400 million vegetarians. Although mainly for religious reasons, these religions are based in pacifism and treating animals equally.
Utilitarians also view all non human organisms on the same level as humans. Everything which possesses life has the same right as another, no matter how insignificant one may seem. Although those who deem themselves Kantian moral saints in deontology find animals as means to an end, some neo-Kantians have begun to adopt the idea that animals have just as much right not to be killed as humans do.