What's in your Pasture?

[Michelle Clarke]

Odd Things that Horses Eat

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
 
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
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)
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
Spinach
Rhubarb stems (NOT the leaves or roots)
Garlic and onions (large amounts may cause anemia)
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: www.ansci.cornell.edu/plants/plants.html.

[Michelle Clarke]

What odd things have you ever seen your horses eat? I have seen mine eat Nightshade, supposedly extremely toxic. However, I also learned that this is only when the horses have been dewormed with an ivermectin product. We have lots of nightshade, so we don't use those products during the times of year when they are out and about. It is also advisable to stay away from those products with young foals who are eating poop - they can colic if they eat poop that has ivermectin in it. That happened with out first filly, Loba, and it was heartbreaking to watch a 3 month old foal thrash around in pain!

Watermelon rinds are a favorite around here! I have found that alot of the wild horses will not eat apples...they even leave them in the bucket if I make it a part of a mash.

My first horse, Arab/QH, would knock you down for a hamburger - 'course he was weird anyway!

[lindad]

Good article, Michelle. I was surprised that nightshade was not on the toxic list as it can be very toxic! We must remember that some of the things that a horse might eat at one time of the year and not suffer obvious side effects, may become lethal another time of year. I had that happen with Rhododenderon and a goat. Plants can become more toxic as they wither, or are going dormant for the winter as happened to the goat. Downed branches can be a problem for this reason, and they may taste sweeter as they wither like dried fruit does. Some things have an accumlulative effect as they eat it over time and the toxins eventually collect or overwhelm the liver or kidneys. Here in Michigan, my horses have killed trees in the winter by eating all the bark and never touch it the rest of the year. That is why it can be beneficial to let the horses have access to straw or low quality hay to fill the need to graze even though they have met their nutritional requirements. it can keep them from eating those things they normally avoid. Thus, my comments to Nola, about concentrated feed for rapid weight gain especially this time of year. Horses have the munchies like people do, and more so becaused they are designed to eat most most of the day, and need to eat much of the day.

When my Kigers came they did not have a clue about any food other than grass and hay, or what occured naturally. I think that was a good thing because the are easy keepers. Now they beg and expect treats and I have to be concerned what others may offer them. Before, I made them aware of other good things to eat, they would not have accepted anything from anyone, which is much safer for all animals, but not nearly so fun or so interesting to them. My daughter's old mare would eat anything, stole balogna sandwhiches. She would push you aside to pick blackberries along the trail, picking them as nimbly as if she had fingers. My daughter used to worm her Zonkey by making a wormer sandwich. We can buy surplus high quality bread (not cheap, soft white bread) very inexpensively, and will give it in small quanities as a treat. (Beware the soft white bread can end up a dough ball in their belly). Lisa used that to her advantage to worm the Zonkey who was leary of being handled. She ate it and wanted more.

Linda D

[DianneC]

I went through the pasture one time chopping down all the Canadian thistle before it bloomed. To my surprise the horses were crowding behind me to eat it. With it cut down they could start on the stem and work up, somehow avoiding the thorns that can go right through a tennis shoe. They also like them as they are coming up and still tender.
We should hire a couple of the horses out for clearing the huge himalayan blackberries thickets that grow here. My friend cuts paths into the big thickets and Oso munches all the leaves, killing the blackberry. Most horses eat the new leaves but he has eaten them all for several years with no ill effects.
I've heard that a main winter food for Indian ponies on the plains was cottonwood bark. The inner cambian layer is safe on many trees. Mine like the alder trees.
One thing we have to watch for is a very poisonous plant called poisonous hemlock. It is a lovely plant about 4-5 foot tall when grown with MANY branches and blossoms like Queen Anne's Lace (no branches). When it is small in spring it looks like a very ruffled fern or little carrot and that is the time a horse might eat it as they graze. Fortunately, it doesn't taste good. All parts are poisonous and it spreads rapidly.
Here is a link to pictures cal.vet.upenn.edu/projects/poison/plants/pppoiso.htm and other poisonous plants.

[fantasykiger]

What's in my pasture? nothing but dirt and Juniper trees..LOL. great article though very interesting.
Funny you should mention wild horses will not eat apples, my BLM MUstang mare still will not eat apples, she is picky about treats. I do have a Morgan mare that is a vaccum she will inhale anything you put near her mouth. Potato chips a top favorite. Fantasy is the only one who is trained to drink out of a glass and loves Coke.

[dara]

My BLM mare used to get into the chicken house and eat all the eggs! she LOVES to crush the egg in her mouth then suck all the yolk just like when she drinks water. I still give them to her occ. but always worry about an enrolith forming from the shells.
Both of my horses also like to eat thisels, and one mare has killed many oak trees by eating All the bark she can reach.

[stlkigers]

Dec 16, 2007 8:23:46 GMT -5 Michelle Clarke said:

Watermelon rinds are a favorite around here!

Michelle:

Good to see someone else's horses enjoy watermelon rinds too! My horses see them in my hands and 3 of the 4 will race to be the first to me to get a juicy piece of rind! My neighbor is spoiling them; they bring me so many rinds over to give to the horses I end up throwing lots away, but I don't want to tell the kids cause they LOVE bringing them over for me to feed to the horses.... Ah, sweet summertime!

Angela

[DianneC]

Last year we gave a few corn stalks to the horses after the ears had been harvested but the stalks were still green. Chinny would manage to fold it up in his mouth so that no other horse could get a piece and then would munch it with great satisfaction.