Management of the Overweight Horse

Management of the obese horse requires changes in the feeding program as well as the exercise program. Obesity in horses, as in humans, is detrimental to overall health and performance. Overweight horses are easily fatigued, have increased sweating to try to cool themselves, increased respiratory efforts and increased leg trauma.

A body condition scoring system, developed at Texas A&M University, provides a universal system for evaluating body fat in horses. This numerical system enables horses to be compared to ideal body condition and monitored for changes. (See technical bulletin “Body Condition Score Your Horses” EB02).

There are several causes of obesity in horses:

Too much energy (calories) consumed
Too little exercise and
Certain medical conditions.

If the horse is otherwise healthy, decreasing energy (calorie) intake while increasing the exercise program is the preferable way to decrease the weight of the horse.

First, evaluate the current diet. This includes everything the horse eats each day, forages and grains as well as the amount of each one. The total daily diet is what must be determined. The goal is to meet all of the horse’s total daily requirements for protein, minerals, vitamins and fiber to maintain gut function, while reducing energy (calories) enough to lose weight.

Forages for the Overweight Horse

Forages include hay and pasture. Hay is generally lower in energy than pasture. This is because the plant is more mature when it is made into hay as compared to when the horse eats it as pasture. For a weight loss program hay is recommended.

There are two general types of hays, grasses and legumes. Grass hays are timothy, orchard grass, fescue, coastal Bermuda, brome, etc. Legumes are alfalfa and clover. In general, grass hays are lower in energy or calories than legume hays. Therefore, grass hay is recommended for a weight loss program.

The chart below shows the typical energy or calorie value per pound for the different forage types:

Forage Type	Mcal/lb.	Kcal/lb.
Grass Hay	0.7-0.9	700-900
Grass Pasture	0.9-1.1	900-1,100
Alfalfa Hay	1.0-1.1	1,000-1,100
Alfalfa Pasture	1.1-1.3	1,100-1,300

Grass hays are an excellent source of fiber for the horse, as well as adding some of the other nutrients to the diet. Fiber is needed to maintain normal gut function, so reducing the amount of hay or fiber in the diet can be detrimental to the horse’s health. Reducing hay too much without adding another fiber source can result in vices and eating bedding or other undigestible fiber sources. This can result in digestive upsets and colic.

Typical grass hays available today will not meet requirements of the mature horse for protein, minerals or vitamins. These nutrients must be added to the diet from other feed sources.

Feed Sources (concentrates) for the Overweight Horse

There are two methods to provide the protein, minerals and vitamins without the significant increase in calories provided by most grain mixes.

Feed a reduced energy feed. Show Formula feed provides a balanced feed for the horse but keeps the calories to a minimum. This texturized feed is formulated to fit a weight loss program while not falling below the other nutrient needs of the horse. This feed allows the owner to continue to give the horse a “grain mix” at 4 to 5 pounds per day and not increase calories.

Feed a protein mineral and vitamin concentrate balanced to feed with grass hay. Gro’N Win is a pelleted ration balancer formulated to be fed in very small quantities (one pound per day for the 1,100 lb. mature idle horse). This will provide the nutrients missing in the hay to balance the total daily ration.

Total Daily Feed Consumption

Total daily feed consumption that includes both the hay and the concentrate portions of the diet should be 1.5% to 2.0% of body weight. This is the total amount that must be provided to the mature idle or light working horse or the same problems associated with lack of hay will result. As an example, the minimum total diet intake for a 1,000-pound horse would be 15 to 20 pounds per day. If five pounds of grain or concentrate is fed then a minimum of 10 to 15 pounds of hay must be fed.

Exercise

Once the nutrition program is set gradually increasing the exercise program is also recommended. This will accelerate the weight loss program as well as condition the horse to be a healthier animal.