Sarah L. Ralston, VMD, Ph.D., dACVN, Department of Animal Science, Cook
College, Rutgers University

Fact Sheet #062 – Reviewed 2004

Horses are adapted to a diet based primarily of forages. Their digestive systems are geared toward the digestion of high roughage feeds that change slowly (for example, sudden access to a bag of grain or lush pasture after they have eaten only dry hay for the previous 5 months is likely to result in colic). However, with domestication, confinement, and modern technology, we are often confronted with horses that consume some really “odd” things with apparent relish. Feeding practices around the world differ and horses in other countries are commonly fed things that average American horse owners would never consider offering to their horses. For example, European horses are routinely fed silage, horses in Saudi Arabia munch happily on dried fava beans, and Irish horses are offered a weekly pint of ale or stout! With the above digestive constraints and variation in mind, what is presented here is by no means an exhaustive list of non-traditional things that might be consumed by horses. It is a list of things that horses have been reported to eat by veterinarians and horse owners around the world. Those that might adversely affect the horse’s health, and therefore be avoided or at least limited, are so identified.

Oddities often consumed by horses on pasture  [I do not consider these plants to be ‘oddities’ but a ‘staple’ for horses on pasture]
No problem, assuming fairly limited quantities and otherwise balanced ration:

Dandelion

Thistle (NOT Russian Knapweed or yellow star thistle–Centaurea spp)

Sunflower seeds and plant

Peanut plants

Raspberry/blackberry bushes

Wood/bark of most trees (NOT Prunus spp or black walnut or locust)

Potential problem if eaten in large quantities
Buttercup

Morning glory

Pokeweed

St. Johnswort

Gum-weed

Astragulus and Oxytropis spp/(vetches and locoweed)

Avocado leaves

Bracken fern

Most bulb type flowers (tulip, iris, etc.)

Wilted red maple leaves  [Red maple FRESH on tree are OK … still exercise caution. It is the WILTED leaves, especially those separated from the tree that are lethal. Brown, dead, crunchy leaves are no issue at all.]

Acorns/new oak leaves

Avoid at all costs (Lethal or severe toxicity potential)
Lily of the Valley

Larkspur

Tomato or potato plants

Rhubarb leaves and roots

Poison hemlock

Foxglove

Leafy spurge

Mustards

Jimsonweed

Alsike clover

Blue flax

Sorghum (Johnsongrass and Sudan grass)

Oleander

Privet

Japanese Yew (all Taxus spp)

Azalea

Rhododendron

Mountain Laurel

Pits of peaches, cherries, or avocados

Horsechestnut

Russian Knapweed or yellow star thistle–Centaurea spp

Potential Treats
Perfectly acceptable treats (fed in limited quantities(<1-2 lbs/feeding)

[Any one of these can be incorporated into a daily “salad” for a horse. See the base diet we use here on PENZANCE here…  http://www.tierneymissionbelize.org/thepenzancehorse/BASICDIETHANDOUT.pdf ]

Carrots, apples, grapes

Bananas

Peas

Green beans

Lettuce

Celery

Dried beans, such as pinto, red, fava (however should be cooked or heat treated)

Watermelon rinds

Squash

Mangoes (not the seeds)

Raisins

Bread/bagels/cake (NOT if they contain chocolate or poppy seeds)

Pasta, macaroni

Potato chips and potato products

Rice products (not raw rice)

Barley products

Corn products

Dairy products

Eggs

Fruit juices

Hot dogs, hamburgers, tuna fish, ham or even roastbeef sandwiches!

Most dog and cat foods

Beware large quantities, but probably acceptable in very small amounts (<2 to 4 ounces/day)

Cabbage, broccoli, kale, chard, collard greens, brussel sprouts [CABBAGE IS ESSENTIAL FOR THE HORSE THAT IS SUFFERING FROM ULCERS OR DEVELOPING ULCERS. Just a small handful of shredded cabbage a day will help turn around a horse with bleeding ulcers !!! in just 3 weeks. Scoped and veterinarian verified.]

Spinach

Rhubarb stems (NOT the leaves or roots)

Garlic and onions (large amounts may cause anemia) [https://fbresearch.org/coconut-and-onion-dewormers/ — BOTH garlic and onion are offer effective parasite control!  Combine with raw, virgin, organic coconut oil]

Turnips

Radishes

Avocado (NOT skins or seeds)

Lathyrus spp. beans (India)

Sunflower seeds

Sugar candies such as jelly beans, gummy bears, peppermints, etc.

Safe in very limited quantities BUT WILL CAUSE POSITIVE DRUG TESTS
Morning glory plants

Sassafras

Willow leaves and bark

Yucca

Tobacco (consumed, not inhaled)

Valerian root

Carrots in very large quantities only (over 5 lbs day)!

Persimmons (seeds also may cause impaction)

Chocolate in any form

Licorice?

Cinnamon products

Nutmeg

Hot pepper/chili flavored products (Nacho chips, etc)

Non-decaffeinated coffee or tea in any form

Caffeinated sodas

Alcoholic beverages?

Some dog/cat foods (Beware “bakery waste” as an ingredient-may contain chocolate)

Summary

There are obviously a wide range of things that our horses may enjoy consuming, not all of which are good for their health. Many horses would refuse to even sniff many of the items listed above. Knowing which potential treats are safe, at least in limited quantities, is important for horse owners. You never know what might be offered to your horse! For more information on signs and sources of toxicity the author recommends the following resources:

Reference

Lewis, Lon. 1995. Feeding and Care of the Horse, 2d ed.

Williams and Wilkins, Philadelphia, PA. Excellent chapters on toxic plants and feed induced diseases.
Toxic Plants Website: Excellent site with many links to other resources:http://www.ansci.cornell.edu/plants/plants.html.