A line drawing of a crossection of a cow's skull.

How To… Kill Animals Humanely

By Michael Sappol

Is empathy innate? Are we all born with the ability to identify with the emotions of others, to feel someone else’s pain? Today’s media is chock full of stories about experiments in neuroscience and child psychology that seem to show that the emergence and growth of the ability to empathize is a natural part of human psychological development, present even in toddlers.

Yet human beings periodically commit terrible acts of cruelty and violence, and are often indifferent to suffering. What if the development of empathy is a precious and fragile cultural accomplishment, something that has developed in fits and starts over time, in certain historical moments, in certain places, among certain people? Maybe most people have the ability to empathize, but what if empathy is a set of practices and beliefs that have to be learned and cultivated in order for individuals to exercise it? Those practices and beliefs would, of necessity, only fully develop in a society that has come to place a high value on empathy, that formally and informally rewards empathic behavior and punishes cruelty and indifference, a society that devotes resources to teaching, rehearsing and developing methods of empathy.

Title page of the pamphlet How to Kill Animals Humanely, including an illustration of a cows head and a Surgeon Generals Office Library stamp.
How to Kill Animals Humanely, 1879. By D. D. Slade, M. D.

How to Kill Animals Humanely is a relic of the history of empathy. English-speaking people originally used the terms “human” and “humane” interchangeably, merely to distinguish human beings from other “brute” animal species. Sometime in the early 18th century, “humane” began to have a special use: to denote a compassionate, caring attitude toward the suffering of other humans and animals, a profound sensitivity that was both a moral obligation and a psychological condition. The word “humane” increasingly came to be used in opposition to “inhumane,” a term that was applied to acts of cruelty to other living beings, and to the people who took pleasure in inflicting suffering or who were just callously indifferent. In the 19th century, “humane” societies were founded to “prevent cruelty,” first to animals (and later to children), first in Great Britain and then in the United States.

This pamphlet, a publication of the Massachusetts Society for the Prevention of Cruelty to Animals (MSPCA), is both a polemic against “needless cruelty” and a handy guide for those who are obliged to slaughter animals for food, medical research, or—in the case of injured or ailing animals—for purposes of euthanasia. “If you must kill them, do it without cruelty. Every animal has a right to justice and protection at the hands of the superior animal—man….” (This was very unlike contemporary antivivisectionism and vegetarianism, and later People for the Ethical Treatment of Animals, which absolutely opposed the slaughter of animals, and which criticized the very notion of human moral superiority.)

The author, Dr. Daniel Denison Slade, was a socially prominent surgeon and veterinarian, founder of the Boston Veterinary Institute, professor of applied zoology at Harvard, director of the MSPCA, and a man of many other interests. Being a veterinarian of longstanding practice, Dr. Slade was an expert on animal slaughter. In his little pamphlet he considers how “the Jews,” Germans, French and Dutch do their killing, but in the end makes his own recommendations, supplemented by helpful illustrations. Ways to kill animals “in the most humane manner possible,” must vary according to the varying anatomical structure of different species: horses, cows, dogs, pigs, cats, poultry, Dr. Slade tells us. Even fish should be killed humanely. For most mammals, the creature should receive powerful blows to the head with a mallet— precisely where depends on the species and individual beast—stunning the animal into unconsciousness, and then finishing it off with more blows or a bullet or a blast from a shotgun. Slade also considers other techniques to lessen the suffering, even chloroform. But he warns against “pithing” a method “commonly in vogue,” in which the “spinal cord is severed or punctured between the first and second bones of the neck.” Such an approach, he worries, is “undoubtedly attended by more suffering than other methods.”

Although humane techniques of slaughter may require some practice to get right and a bit more work, Slade argues, they can also improve “the wholesomeness of meat for food, and the market value of the animal slaughtered; there being no question as to the effects of torture, cruelty and fear upon the secretions, and if upon the secretions, necessarily upon the flesh.” He finishes the pamphlet with a long listing of the mission and accomplishments of the MSPCA (including the provision to Boston police stations of “hammers and hoods for killing horses mercifully”), followed by the Society’s “thirty-nine articles of faith” and a fee schedule for membership.

D. D. (Daniel Denison) Slade (1823–1896), How to Kill Animals Humanely (Boston: Issued by the Massachusetts Society for the Prevention of Cruelty to Animals, [1879?]). 15 pp., illustrated. 4” x 6½”.

Read other How To… features from the NLM Collections here.

profile portrait of Michael Sappol in ChicagoMichael Sappol is a historian in the History of Medicine Division of the National Library of Medicine.


  1. I laud this article for its emphasis on the humane killing of farm food animals. What is of equal importance is the suffering and cruelty that these poor creatures endure during their short lifetimes. For example calves deprived of their mother’s milk, young animals not allowed to interact and play with their peers, young pigs having their noses amputated while alive, keeping animals confined in cramped quarters, unable to move. Yes, the litany of abuses goes on and on. It can be argued that the animal is unaware that the terminus is coming because an animal lacks human cognition.I beg to differ.If you have ever seen cattle being led up the gangplank to be slaughtered, how they buck , resist and try to flee. I think they know what awaits them, they have a sixth sense which we humans fail to appreciate. As time goes on science finds more and more evidence on how surprisingly intelligent these dumb creatures really are.

  2. Interesting article. This was I believe during the same era when anti-vivisectionists were speaking against the use of animals for scientific experiments. The more progressive scientists naturally defended the practice – Dr. James Blundell of transfusion fame comes to mind. He wrote an eloquent argument defending vivisection and attacking his detractors.

  3. Blundell’s defense of vivisection was some 50 years earlier, in response to the 1824 founding of the Royal Society for the Prevention of Cruelty to Animals (RSPCA), which inaugurated the modern antivivisection movement. In 1825 Blundell gave a lecture in London that argued that the sacrifice of animals in medical experimentation was almost a “sacred duty” to those who were seeking to expand medical knowledge, find disease cures, and reduce human suffering.

    1. And here is part of what he said:

      “It is not the infliction of pain or death for justifiable objects, but it is the taking a savage pleasure in the infliction of pain or death, which is reprehensible. Here, then, we take our stand; and we defy the puny drivellers of the press, the declamatory and spurious orators of the day, to drive us from it. We defend the sacrifice of animals, in so far as it is calculated to contribute to the improvement of science; and, in those parts of physiological science immediately applicable to medical practice, we maintain that such a sacrifice is not only justifiable, but a sacred duty.” – James Blundell

      Pettigrew TJ. James Blundell, M.D. In: Medical portrait gallery. Biographical memoirs of the most celebrated physicians, surgeons, etc., etc., who have contributed to the advancement of medical science v. 1. London: Fisher, Son, & Co.

      1. The taking of ” savage pleasure in the infliction of pain or death” is sadism, pure and simple.

  4. I just raise a simple question for those, who hate to kill animal for food.
    What tiger, lion, and other similar animals eat? They need to kill other animals for survival. We, human can survive without killing animal. We can live on vegetables. My question is, why? The earth is a place for survival of the fittest. That spacies extincted who got no food. Animals are treated as our food. How could a vegeterian claim to be not cruel, when he eat vegitable? A froot contains seed of a tree, this is scientifically proived that plants, vegetables trees.. . everything we see that grows, reproduces, is live. Eating a froot picking that from a tree is same cruel act like eating meat. We need to eat for living. No way to show mercy to certain species. I feed my pet to become healty, so that I can get more food. You can love that pet, just like you love your froot garden. Do not think ever not to eat meat.

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