Equine gastric ulcer syndrome is a common condition in performance horses. More than 60% of performance horses may suffer from gastric ulcers at some point in their career due to the stressful demands of their lifestyle. To address the issue, many horses receive the drug omeprazole (i.e. UlcerGard® or GastroGard®). Research from the scientific community is beginning to uncover negative side effects that may be associated with the use of omeprazole, and has suggested plasma and seaweed-derived calcium as potential drug-free alternatives.
What are Gastric Ulcers?
Over 95% of racehorses and 60% of performance horses will develop ulcers during their career. Many people think of ulcers only in high level performance horses, but research now shows that up to 37% of horses used for leisure, including light work and trailering, are also affected by gastric ulcers. Gastric ulcers are the result of acid in the stomach damaging the stomach lining. Ulcers typically occur when a horse is under stress – either physically, environmentally, or emotionally. Examples of stress that are known to induce ulcers include: being housed in stalls, intense training programs, hot weather, high starch grain meals (i.e. oats, corn, sweet feeds), trailering, emotional distress (i.e. change of ownership or loss of buddy horses), performance anxiety, and the daily demands and schedules associated with being a performance horse.
What is Omeprazole?
The drug omeprazole (oh-mep-ruh-zohl) is a proton pump inhibitor used to treat stomach ulcers in horses. It acts by inhibiting or reducing the production of stomach acid, thereby changing the pH in the stomach. This modification of the horse’s normal biological system offers existing ulcers the time to heal while also preventing the onset of new ulcers. The most common protocol for a horse diagnosed with ulcers is to administer omeprazole (4 mg/kg BW) daily for 28 days, and then continue for an additional 4 weeks at a reduced rate (2 mg/kg BW), followed by a further reduced rate (1 mg/kg BW) to be used only on days of added stress.
What are the Side Effects of Omeprazole?
A recent study led by Dr. Joe Pagan of Kentucky Equine Research found that omeprazole limits calcium digestibility. His team suggested that long-term use of omeprazole combined with low calcium intakes and the use of furosemide (Lasix®) may compromise calcium balance in the horse. Brazilian researchers found that just 11 days of omeprazole treatment caused changes in how horses metabolize fats, proteins, and minerals. A 5-week study in chickens found that omeprazole administration reduced bone density of the femur and increased gene expression of the parathyroid hormone, a calcium-regulating hormone that plays an important role in bone remodeling and maintaining serum calcium concentrations.
Alternatives to Omeprazole
Research at Iowa State University’s Veterinary College found that feeding horses a daily plasma supplement effectively prevented gastric ulcers in horses experiencing stress from exercise and training. This research-proven ingredient can be found only in LIFELINE+ Equine by Stride Animal Health and Equilene® Pro Care by Bluebonnet Feeds. Another alternative is Seaweed-Derived Calcium. This ingredient has a unique honeycomb structure which offers an unusually high capacity to buffer stomach acid, compared to calcium carbonate. Using a feed that contains both plasma and seaweed-derived calcium (i.e. Equilene® Pro Care) is an excellent step toward drug-free ulcer prevention.
There are also several management techniques that provide an opportunity for preventing ulcers in horses. If possible, allow your horse to be turned out into a large paddock or pasture where they can move around freely. Ensure they always have access to roughage (i.e. pasture grass or hay). Saliva is the horse’s natural buffer to stomach acid, and horses only salivate when they are chewing, therefore the simple act of providing 24/7 access to forage can help prevent ulcers from starting. If possible, ride in the early morning or late evening when summer temperatures are at their coolest. Limit hauling stress by making frequent stops that will allow horses to relax. When driving, always ease into starts and stops and take corners slowly. If the trip is long, hang a hay bag, and offer water every 4 hours.
If you suspect your horse may be in need of a specialized nutrition program, or if you just want a nutrition consultant to review your horse’s current diet, Bluebonnet Feeds offers free virtual nutrition consults.