Carbohydrates in Horse Feed

Carbohydrates in Horse Feed

Carbohydrates are the collective names for starches, sugars and dietary fibres that can be digested in some form to provide energy

A horse is essentially a carbohydrate converter, since its diet is typically comprised of upto 80% carbohydrate

In horse nutrition, carbohydrates fall into one of two categories 

• Structural carbohydrates
• Non-structural carbohydrates

Structural Carbohydrates (fibre)

Can’t be digested by animals, thus digestion takes place in the hindgut by microbial fermentation and then absorbed into the bloodstream and are the main energy source for most horses.  

This takes time and as there is no rush of energy, energy derived from fibre is said to be “non heating”

The following table gives the typical fibre content of various horse feeds

Non-Structural Carbohydrates (sugars and starches)

These are starches and simple sugars that can be broken down in the small intestine, and the end products are sugars that are absorbed from the small intestine

This energy is more rapidly available to the horse and is often referred to as a ‘heating’ type energy as the rapid increase of energy can make a horse excitable

A large meal high in starch and sugar causes a rise in blood glucose with a concomitant rise in insulin shortly after.

Any starch or sugar that passes through the small intestine ends up in the hind gut and the end product of this fermentation is lactic acid which alters the gut environment (upsets the bacterial flora / microbes). Even a partial overload can have a marked effect on the horses well being. Mild signs include loose droppings to the worst which is colic and laminitis

As a general rule of thumb with starch ....

Chaffs (lowest) 8 Cubes (higher) 8 Mixes (highest)

The following table shows approximate starch and sugar content of various horse feeds

Feed manufacturers are responding to the demand for horse feeds low in sugar and starch and now you can find chaffs and fibres, such as Hi Fi Molasses Free with starch and sugar contents less than 2%.  Unmolassed sugar beet such as Speedibeet are also extremely popular due to their lower sugar content

Some general feeding guideline to prevent starch and sugar overload

• Never feed more than 2kg of hard feed at a time
• Keep starch intakes below 0.25% of body weight equivalent to 0.9kg of starch per meal
• In high risk horse, opt for low starch feeds, cubes are always lower than mixes, and chaffs lower still

Also see our guide to Oils and fats in the horses diet and Protein in the horses diet