Equine
Grain Overload in Horses
By Dr. Devon England
You come home after a long day at work, and your feed room door is wide open and grain bins are empty. What do you do? Before you call your vet, figure out what grains were eaten, try to estimate how much and determine which horse or horses got into the feed. Did your horse just get into some hay or alfalfa pellets, or did he get into a high sugar grain like Omolene 300? Did your horse get into chicken or cattle feed? If he did, is it a medicated feed, containing an ionophore like monensin or lasalocid?
Grain overload is an emergency, with better outcomes, the sooner the horse is treated. So, call your veterinarian as soon as you figure out a possible grain overload has occurred. Based on what feed and how much feed your horse consumed, your veterinarian can try to determine the risks to your horse and come up with a treatment plan. Signs of grain overload include colic, lethargy, inappetence, diarrhea and lameness. These signs will vary depending on how long ago grain ingestion occurred and the severity of grain overload.
If your horse got into hay or alfalfa pellets, these are low in sugar and therefore not a high risk for problems. Your horse may just have a mild belly ache (colic) episode. If your horse got into a feed like Omolene 300, they are at risk for grain overload. How severely they are affected will depend on a few factors including how much grain was eaten (5lb vs 30lb), if the horse normally receives that grain or doesn’t receive any grain, and the size of the horse vs the amount of grain eaten. Eating 5lb of grain for a full-size horse who normally receives grain may not be a problem, but that same amount of grain eaten by a small pony who normally only receives hay will be a problem.
Treatment for grain overload should be initiated as soon as possible. This includes lavaging the stomach to remove any remaining grain. Stomach lavage is only successful in removing feed within the first couple of hours. Horses will be given mineral oil or charcoal to decrease absorption of breakdown products (acids) from grain fermentation and protect the intestinal lining from damage. Intravenous fluids are given, because horses can quickly become dehydrated with grain overload, due to digestion products from the grain drawing in a lot of water into the colon. Anti-inflammatories, lidocaine, and ice boots are used in more severe cases to decrease the risk of laminitis. In more severe cases with damage of the intestinal lining, antibiotics may be used to prevent infections associated with bacterial escape from the damaged intestine.
If your horse got into medicated feed containing an ionophore, your horse is at high risk for heart failure and muscle damage, on top of grain overload. Ionophores are toxic at very low doses in horses (2mg/kg). These drugs are added to livestock feed to decrease parasites (coccidia), to help with feed efficiency, to decrease risk of bloat and to decrease methane emissions. If your horse has eaten ANY amount of medicated feed, they should be immediately seen by your veterinarian, even if they are not showing any clinical signs. Horses can have no clinical signs or be mildly lethargic in cases where small amounts of medicated feed were eaten but still have evidence on blood work or muscle and heart damage. Clinical signs include initial inappetence or colic signs, weakness or neurologic signs in the hind end, muscle fasciculations (twitching), laying down more, and not being able to stand. There is no anti-dote to ionophore toxicity. Treatment may include mineral oil, IV fluids, anti-inflammatories and supportive care, depending on how soon toxicity is identified. In severe cases, horses can die or develop heart failure, necessitating euthanasia. In less severe cases, especially if identified and treated early, horses can recover fully.
Grain overload can come with serious complications if severe or medicated feeds are involved, especially if treatment is delayed. Secure your feed room as best as possible and keep medicated livestock feeds in a separate location to prevent cross-contamination. And if you have any concerns about your horse getting into feed, call your veterinarian as soon as possible.
This article was originally published in the February 2025 issue of Oklahoma Farm & Ranch.
Equine
Vaccines: A Practical Part of Horse Health
Vaccinations may not prevent every case of illness, but they remain one of the most effective tools horse owners have for reducing the risk of serious and sometimes fatal disease. The right vaccination program depends on the horse, where it lives, how often it travels and the animals it may encounter.
The American Association of Equine Practitioners divides vaccines into two categories: core and risk-based. Core vaccines are recommended for all horses because the diseases pose a significant health risk, may have public health implications or are spread by sources that owners cannot completely control. The core vaccines for horses are tetanus, Eastern and Western equine encephalomyelitis, West Nile virus and rabies.
Tetanus is caused by bacteria commonly found in soil and manure. The organism can enter through puncture wounds, cuts, surgical sites and other damaged tissue. Even a wound that appears minor can create an opportunity for infection. Previously vaccinated adult horses generally receive a tetanus booster annually. An additional booster may be recommended following a penetrating injury or before surgery if more than six months have passed since the horse’s last dose.
Eastern and Western equine encephalomyelitis and West Nile virus are spread primarily through mosquitoes. These diseases can affect the nervous system and may cause weakness, loss of coordination, behavioral changes, difficulty standing or death. Vaccination is generally scheduled before mosquito season begins. In regions with long mosquito seasons, a veterinarian may recommend boosters more frequently than once a year.
Rabies is uncommon in horses, but it is fatal and can be transmitted to people. Horses may be exposed through contact with infected wildlife, including bats, skunks, raccoons and foxes. Because horses frequently interact with owners, veterinarians, farriers and other handlers, annual rabies vaccination protects more than the individual animal.
Risk-based vaccines are recommended according to a horse’s individual circumstances. These may include vaccines for equine influenza, equine herpesvirus, strangles, leptospirosis, botulism and other diseases. A horse that remains on one farm with a closed herd may have different needs than a show horse that travels regularly, shares barns with unfamiliar horses and encounters animals from several states.
Influenza and equine herpesvirus vaccines are commonly considered for horses that travel or are frequently exposed to new horses. Equine influenza spreads quickly through respiratory droplets and contaminated equipment. Horses at increased risk may need boosters every six months, and some competitions or facilities require proof of recent vaccination.
Timing also matters. Vaccines do not provide immediate protection, and an unvaccinated horse may require an initial series of two or more doses. The AAEP recommends completing the primary series and needed boosters at least 14 days before likely exposure. Waiting until the day before a show or hauling trip does not give the immune system enough time to respond.
Mild soreness, swelling or a temporary fever can occur after vaccination. Serious reactions are rare, but owners should contact their veterinarian if a horse develops significant swelling, breathing difficulty, hives, weakness or other concerning signs.
There is no single vaccination schedule that fits every horse. Age, pregnancy, health, travel, local disease activity and previous vaccination history all affect the plan. A veterinarian can also make sure vaccines have been properly stored, administered and recorded.
Vaccination works best alongside good management. Clean equipment, limited contact with unfamiliar horses, isolation of new arrivals and prompt attention to illness remain important. Together, vaccination and basic biosecurity provide horses with a stronger line of defense against preventable disease.
Equine
The Pull of the Barn
When I was younger, I saw plenty of old Westerns. They were fun to watch, but one part always stressed me out. Inevitably, a cowboy would get shot or thrown from his horse, and while the cameras stayed on the fallen rider, I worried about the horse. Would it wander around lost on the prairie, never finding its way back? The truth is, most horses know exactly where home is. Turn one loose, and it will drift toward the barn. Ride one out, and the trip away from home feels steady, but the return picks up pace the moment the barn roof comes into sight. We even have a name for it: barn sour.
Horses are prey animals, and survival has always depended on familiar ground. For a domestic horse, the barn means food, water, and the company of the herd. Ethologists (scientists who study animal behavior) point out that horses are quick to learn patterns. When hay and grain appear in the same place every day, that spot becomes magnetic. Over time, repetition lays down mental trails as clearly as cattle wear down physical ones in a pasture. What appears to be stubbornness is actually instinct. The barn equals safety, and safety equals survival. Riders from cavalry days to modern ranches have written about horses quickening their pace on the way home. And though the land changes, that pull never does.
People are not so different. We all have barns in our lives — comfort zones we gravitate toward, routines that steady us. They serve a purpose. Like a horse standing at the gate, we lean on safe ground when life feels uncertain. But the pull can also hold us back. A horse that refuses to leave the yard never discovers what lies beyond the fence, and the same is true for us.
That balance shows up in history too. Old cattle trails once served their purpose, guiding herds north and helping to build economies. But when railroads and fences changed the landscape, those well-worn tracks became ruts. Progress required new paths. Our own habits work the same way. Some keep us grounded. Others only circle us back to where we started.
When I see my horses drifting toward the barn, I think less about impatience and more about instinct. They are drawn to the familiar, and so am I. The barn matters. It is the anchor point, the place of rest. But the pasture matters too, because growth is waiting outside the gate.
Those old Westerns had it right in at least one way. The cowboy’s horse was never going to wander off aimlessly. It would head back to camp, back to the barn. That simple truth still plays out in every pasture and arena today. Horses know where home is. The question is whether we will let the pull of our own barns keep us tied too tightly, or whether we will use them as a base to step farther into the wide-open ground ahead.
Equine
Trailer Safety Checklist
By Janis Blackwell
As the season arrives to gear up for participation in your equine event of choice, one thing remains a constant for all horse owners. That constant is our responsibility to insure the safety of our horses by being diligent to maintain the integrity of the trailers in which we haul them. There are a number of things that can be dangerous both inside and outside of your trailer. Whether you traveled all winter long or whether your trailer sat unused or was used very little through the cold weather months, at least once a year your trailer is due a thorough going over. So here we go with a checklist that will help you insure a happy and safe trip for you and your equine partner.
- A sound floor is absolutely imperative. Whether your floor is aluminum, steel or wood, it should be cleaned regularly after use to preserve it. Urine and manure will erode and weaken all types of floors. Even rubber mats will not prevent erosion of your floor. (Maintenance tip: remove mats and wash aluminum floors often to prevent erosion.)
- Especially check wooden floors for rotten boards. Immediately replace questionable flooring before hauling. (Maintenance tip: For wood, remove mats and wash out manure and debris. Coat wooden floor in a cheap motor oil. Allow to sit in hot summer weather until the oil soaks in. Be careful—floor will be slippery until oil cures into the wood. This treatment yearly will preserve a wooden floor for much longer than normal as it repels urine and protects the wood).
- Keep the interior and exterior washed to enable you to check for rusted out places, leaks, etc.
- Have a professional check your brakes at least once yearly to be sure they are operating properly.
- Be sure tires are inflated to the proper air pressure, and check the inside of each tire for hidden unusual wear that could cause a blowout. Replace worn tires before leaving home.
- Wheel bearings must be checked and packed at least once a year. This should be done even if the trailer has been rarely used since the last time the wheel bearings were packed. In fact, trailer maintenance professionals say that sitting stationary and unused is even worse for the bearings. Improper care and maintenance of wheel bearings can cause a wheel to seize up and actually twist off while in use. Use a horse trailer professional for this maintenance task.
- Axles should be checked for bowing. A bent or bowed axle can cause excessive tire wear and damage wheel bearings.
- There should be no more than two inches in height difference from the front of the trailer to the back. More difference than that causes the bulk of weight of the trailer and its contents to ride mostly on the rear axle causing it to bow and wear on both tires and wheel bearings.
- Another critical part of the trailer to keep an eye on are the butt chain or bar and the back door. The butt chain or bar should be firmly attached to the wall and its keeper and should always be latched. The door should have a strong secure latch with a pin to insure it stays latched while in motion.
- Finally, but certainly not of least importance is a thorough check of the trailer hitch including ball and coupling. Keep the ball well greased. Periodically, check to see that the ball is still securely tightened and the latch on the coupling is working properly.
These few critical safety check points can save you money, stress and the wellbeing of your horse. Until next time, happy trails and safe traveling.
This article was originally published in the April 2016 issue of Oklahoma Farm & Ranch.
-
Country Lifestyle2 years agoJuly 2017 Profile: J.W. Hart
-
Attractions9 years ago48 Hours in Atoka Remembered
-
Farm & Ranch2 years agoFrom Plow to Plentiful: The Most Important Inventions in Agricultural History
-
Equine9 years agoUmbilical Hernia
-
Country Lifestyle5 years agoThe Two Sides of Colten Jesse
-
Outdoors8 years agoGrazing Oklahoma: Honey Locust
-
Farm & Ranch8 years agoHackberry (Celtis spp.)
-
Equine6 years agoOn the Road with Emily Miller-Beisel






