By Sue McDonnell, PhD, Certified AAB May 1, 2003 Topics: Behavior

Newsletters
Last October, we shared letters from three readers describing horses killing and/or eating small mammals and birds (see "Carnivous Horses," article #3832 at www.TheHorse.com). We asked for reader response, and I agreed to contact experts in equine nutrition, behavior, and husbandry from around the world for their comments on the topic. All told, through the magazine or directly, we have had replies from nearly 100 readers. The responses have come from horse owners, trainers, veterinarians, biologists, animal behaviorists, and equine scientists from all over the world. We received many stories as intriguing as the original three, and we wish space allowed us to print them all. I have also had written and verbal feedback from more than 30 equine experts to whom I sent copies of the article. Thank you all for the wonderful letters. As promised, here is a summary of what you all have seen and think about horses killing animals and/or eating meat.


ANNE EBERHARDT

Most readers and experts said they had never seen a horse eat a live or dead animal, but had seen some horses eat meat that was offered or that was inadvertently available, such as by raiding a picnic. (We're not suggesting feeding chicken bones to horses.)

Disbelief and Disgust

First of all, we had three responses--two from life-long horsemen and one from a veterinarian--questioning the validity of the stories we shared. One of these letters suggested that we had been "taken." Another said they would need to see video to believe it. We also had several responses indicating a reaction of disbelief in the sense of horror and disgust, and were very interested in what other readers would say.

Junk Food Meat Eaters

Most of the replies from readers and experts said that they had never seen a horse eat a live or dead animal, but knew that some horses would eat meat that was offered or that was inadvertently available. The reports included domestic horses, donkeys, mules, ponies, and miniatures, as well as wild mustangs. Meat foods mentioned included hot dogs, hamburgers, steak, bologna, ham, fried chicken, or buffalo wings--eaten from the hand or from the tailgate just as if they were apples. Unusual meaty food items included were spaghetti with meat sauce, chicken livers from the trash, whole raw eggs in the shell, meat-based dry dog food, and an entire family Thanksgiving dinner of turkey and trimmings. (Not everyone adequately explained the circumstances, and I am left wondering how that one could happen.) Some indicated that these particular horses were the type of animal that would take almost anything offered from the hand of a human, or that were very mouthy and nibbly around everything. Some horses were described as having apparent preferences and aversions for various non-traditional horse food items--"It's not just that he'll eat anything. He takes meat of any description, but not potatoes." Or, "He picks around the lettuce and onions to eat the hamburger, ketchup, and bun." The nutrition experts and owners alike suggested that the salt or sugar in prepared meats and fast foods are likely attractive to horses. The behaviorists fully understood that horses have learned that what we eat or offer them is tasty.

Salted Fish

A biologist colleague from the Netherlands, Machteld van Dierendonck, who has studied horse behavior in Iceland and Przewalski horses in Mongolia, reminded me that pastured horses in Iceland are provided salted fish as a protein and mineral/salt supplement. She wrote, "In Iceland in winter, where horses are kept mostly at pasture with hay supplement, it is traditional for farmers to place salted herring in big plastic barrels out in the pastures. This supplement is very popular among the horses. The herds gather round the barrels about once a day and each horse takes several bites of the fish. During my field observations in 1999, a 150-liter barrel in a pasture of 34 horses was emptied in five weeks. It's pretty funny when you see a horse take a whole fish at once, and you see the tail extending out through the lips as the head and body are chewed. You can hear the bones crush in their mouths. Afterwards, you see them licking their noses and lips extensively. It is claimed that the fish provide salt, as well as vitamins A and D and selenium, which are reportedly deficient in the native hay and silage. You can also see 'dominance' behavior among the horses, as if this fish is a prized and limited resource. So in many ways, their behavior around the barrels of fish is as it is with a salt/mineral lick."

Playing, Chasing, Attacking, Killing

Many readers sent graphic accounts of horses chasing and attacking small animals and fowl, usually by stomping, pouncing cat-style, or picking up and tossing all sorts of critters. Readers' experiences included, more or less in the order most mentioned: Dogs, rats, mice, chickens, goats, sheep, rabbits, ducks, geese, calves, peahens, turkeys, pigeons, snakes, pigs, squirrels, coyotes, cats, hedgehogs, beaver, bandicoot (Australian cat-sized marsupial), and skunk (yikes!). In many cases, the behavior was interpreted as the expulsion of pesky intruders--sometimes playful, but more often serious. A few readers described their horses' chases and attacks as purely playful, though sometimes dangerous. Many people reported the horse paying attention to or playing with an animal that was injured or killed as a result. Many others reported that they had intervened and removed the dead animal, and so didn't know if the horse would have eaten any meat or blood. They said this article now made them wonder if their horse would have eaten the animal.

Eating Carcasses and Blood

Many readers described finding a horse licking blood or eating a dead animal that they either knew (such as doves or blood from deer killed by hunters) or assumed had been found dead--perhaps died there or had been killed and left by a dog or cat. Jinny Johnson pointed out that Michael Shafer in his book, The Language of Horses, "describes Tibetan post horses eating fresh sheep's blood mixed with millet gruel."

Eating Live Animals

Some readers described having seen horses eating live chicks, mice, and goldfish whole or by biting off and swallowing the head. A typical account of such behavior came by e-mail from Bonnie McClure.

"I've been around, owned, bred, and trained horses for over 50 of my years, and only on one occasion have I ever personally witnessed anything close to 'carnivorous' behavior in a horse, and at the time, I almost doubted my own eyes. One of our Peruvian Paso (a mild-mannered breed) stallions only shows what would be considered anything even close to 'stallion-like behavior' when he is brought out for obvious breeding purposes. Yet he shocked me beyond belief one day, many years ago.

"I saw a peahen with several peachicks sauntering through this stallion's large corral, and as she and the chicks were getting practically underneath the horse, I was concerned that one might accidentally get stepped on if he moved. But, to my relief, they soon seemed to be moving safely out of range, except for one little fuzzy straggler, and as it hurried along to catch up with the peahen and her other peachicks, our stallion reached down and grabbed the peachick in his mouth! I saw the chick's legs and feet sticking out of the stallion's lips, and I was totally horrified, realizing it would probably be dead or injured beyond saving once he dropped it. However, it never fell from his mouth. He obviously swallowed it. I ran straight into his corral, still hardly believing what I'd witnessed, hoping maybe I was wrong and perhaps I'd find the chick lying dead on the ground. But it was nowhere to be found, as the stallion had truly swallowed the 'evidence.' I was totally shocked and disgusted by his incredible behavior, and it took me a very long time to overlook his 'fowl deed' (forgive the pun) and feel the same kindly way about him again. Not since then have I seen him show any 'odd' or aggressive behavior toward peafowl, wild rabbits, squirrels, or anything else that happens to wander through his corral."

Killing and Eating Animals

Just as in our original stories, several readers described eyewitness accounts of horses repeatedly killing and eating some or all of the carcass. The targets included ducks, rabbits, hedgehogs, geese, and newborn lambs.

Dr. Anna Gudrun Thorhallsdottir, an equine nutritionist and behaviorist from Iceland, offered the interpretation of repeated ingestion of blood, viscera, or meat as a learned behavior. She explained it in terms of the horse having a chance encounter--either by finding a dead animal or by killing an animal and while investigating the carcass, getting a taste for the salt or something else attractive, the action thereby being reinforced, and so the horse repeating the behavior. Not evil, but no different from accepting the many unusual but good-tasting feeds we provide horses.

Meat-Borne Disease in Horses

One side note that came up concerned the mystery of horses and meat-borne disease. Dr. Katrin Hinrichs, a colleague from Texas A&M, said: "Reading that article, the first thing I thought of was that this may answer the puzzle of horses getting trichinosis. Two or three times over the 10 years we lived in New England, the horse slaughterhouse in Connecticut (where we got some ovaries for research) was closed down because someone in Europe got trichinosis from eating raw horse meat from the U.S. Since Trichina is only spread by one mammal eating the meat of another mammal (or maybe a bird, I don't remember), I couldn't figure out how a horse could get trichinosis. People suggested that the horses were fed garbage (but I can't believe they'd eat it); I thought maybe they picked up dead mice baled up in the hay (but how long Trichina lasts if the muscle is dried out, I don't know)."

Another interesting note came from Jeremy James, transportation consultant for the International League for the Protection of Horses: "I work live horses transported for slaughter imported into the EU--principally Italy--from Eastern Europe. My organization aims ultimately to replace live transport with a carcass trade. However, I am aware (as is the EU Veterinary Inspectorate) that a number of the 140,000 slaughter horses entering the EU annually carry the parasite Trichina, which is more usually associated with carnivores rather than herbivores. All horses now have to be tested for this--or rather the meat does, since being a filaria it doesn't show up in blood tests. But the more worrying aspect is that it has been transmitted to the human population. There have been outbreaks of trichinosis in humans eating horse meat--either fresh or as salamis.

"In conversation with a distinguished Eastern European Chief Veterinary Officer--who also happens to be an equine vet--he advanced an interesting idea. He asked me if I had ever seen horses eating meat, and I recounted the story of my pregnant Welsh pony (that had eaten a dead sheep). Interestingly, he said that he had also heard of this, particularly in pregnant mares, and wondered that the reason for trichinosis appearing in horses came about from their eating the carcasses of dead rats. It's a chilling scenario, is it not, when one considers the numbers of horses going into the human food chain, even although they may be tested for trichinosis, yet where a number--the illegally imported and the stolen--enter without such checks."

Mythology/Ancient History

Two readers also reminded us of the mythological stories of flesh-eating horses. Charles Yates wrote, "I have always wondered about the legend of Hercules: Labor 8: The Horses of Diomedes (www.perseus.tufts.edu/Herakles/horses.html). After Hercules had captured the Cretan Bull, Eurystheus sent him to get the man-eating mares of Diomedes."

In summary, it seems that while it's quite rare for horses to kill and eat flesh, it has happened many times. One question raised was whether once a horse is seen killing or eating an animal or bloody meat, might people--particularly small children--be next? Most people described that horses which killed and ate animals remained gentle with humans, although some were leery of allowing contact with children. Sadly, one reader wrote of a child attacked and killed by a stallion. Unfortunately, we've known of other children and people over the years that have been viciously attacked and injured or killed by horses. I don't know of any horse that first killed animals, then started attacking people, and none of the replies that described flesh-eating horses described such a case.