ULCER PREVENTION

By Amy K. McLean, PhD

Horses of all ages can develop Equine Gastric Ulcer Syndrome (EGUS). The term

EGUS refers to ulcers in the esophagus, both regions of the stomach (glandular and

nonglandular), the proximal duodenum. The proximal duodenum attaches the small

intestine to the stomach. We know that digestion begins in the mouth through the

process of mechanical breakdown of food particles by teeth and saliva. Saliva is the

first buffering agent that helps break down feedstuffs, so nutrients are more readily

available to access pre-hind gut (cecum). From the mouth, food particles travel through

the esophagus to the stomach. The stomach which is like size of a basketball can be

divided into two sections, glandular and nonglandular (also referred to as the

squamous). The glandular region of the stomach is the lower or bottom part that

secretes enzymes such as pepsin which helps digest protein, bile, and hydrochloric acid

(HCL.) The horse is designed to eat small meals throughout most of the day (16-18

hours). Various acids and digestive agents (as mentioned above) are continually made

in the horse’s stomach that aid with digestion such as hydrochloric acid (HCL).

However, If a horse has an empty stomach, the acid is still produced.

Many studies have focused on performance horses and the incidence of EGUS and few

have studied recreational or breeding stock. We know from performance and racehorse

studies that a large percentage of these individuals have gastric ulcers. The more

intense the exercise or exercise program the higher the risk of gastric ulcers due to HCL

splashing from the nonglandular region of the stomach to the glandular region. When,

this occurred there was an instant shift in pH (less than 4) as well and the more intense

the exercise the bigger change occurred. The severity of ulceration has been shown to

be the greatest in performance or racehorses as high as 90 %. One study found 40% of

156 Western Performance horses to have EGUS and 58% in show horses scoring a 2

or higher. The score reflects the severity of ulceration and the higher the number (4

being the highest) the more concerning the condition of ulceration. Good news, western

performance horses in general had lower percentages of EGUS compared to other

equine athletes and disciplines which relates back to management and exercise

regimes.

How horses are fed can play a pivotal role in the incidence of gastric ulcers and

severity. Horses fed prior to exercising or competing and fed a forage-based feedstuff or

diet with fiber to decrease EGUS. A diet higher in fiber and the horse’s ability to graze

throughout the day can all decrease gastric ulcers because the stomach fills with

feedstuffs that absorb HCL and other enzymes released such as bile, pepsin and lipase

and the acid does not literally splash into the nonglandular region or to the esophagus

or into the small intestine. The process of decreasing gastric ulcers by increasing forage

or forage based supplemental feed begins in the mouth with salvia production. Salvia is

a basic product meaning it has a higher pH. Forages stimulate chewing action and

chewing stimulates salvia. If the feedstuff is now covered in salvia the pH becomes

higher and more basic which can help offset an acidic or low pH environment such as

that of an empty stomach only filled with acid. Several studies have focused on pH as

the main ulcerogenic factor and factors that may lower pH such as diets high in

grains/concentrate and essentially starch.

So, prior to riding or exercising at least thirty minutes out offer your horse a forage

based supplement or forage. This will stimulate chewing in return stimulate saliva

production, increase the pH, and create a positive reaction all the way from the mouth,

esophagus into the stomach and then the pyloric region where the stomach attaches to

the small intestine. Also, consider beginning your exercise at a walk and working up to a

trot or jog and eventually the lope or canter. If you are galloping, consider the amount of

time spent in this faster gait. The longer the horse is exposed to intense exercise or

gaits the higher the chance of developing EGUS and the more challenging it may be to

decrease ulcers but feeding prior to exercise can help. Also, consider products that are

alfalfa based.

The calcium in alfalfa will help soothe the stomach as well like products sold to

decrease the risk of ulcers. The more digestible the fiber or source of fiber such as

alfalfa, again this will promote digestion in the stomach and the stomach will stay filled

longer as it breaks down nutrients such as protein, fats, carbohydrates, vitamins,

minerals, before the feedstuffs enter the hind gut. The goal is to increase pre-cecal or

hind gut digestion, increase the pH of the stomach and decrease the risk of EGUS and

gastric ulcers by offering forage or forage-based products prior to exercise and

throughout the day so the stomach is hopefully never completely empty.

Check out the Alfaforce line of forage-based products to help promote a healthy

gastrointestinal environment pre and post exercise.

More information can be found at

alfaforceequine.com. If you have a specific nutrition question you can also reach out to

Dr. Amy at sweetwilliam27@hotmail.com