Crude fat

What it is

Crude fat is measured by extracting the feed with ether. Most forages contain less than 3% fat ^[1].

As an energy source

Fat contains about 2.25 times the energy of carbohydrate or protein, which makes adding fat the easiest and safest way to raise a diet's energy density ^[2]. Vegetable oils and other high-fat feeds supply roughly three times the energy of grains such as oats and maize by volume ^[2].

Using fat instead of grain lets a horse keep more of its diet as forage. When high-starch concentrate replaces forage beyond about half of the diet, the microbes of the caecum and large intestine are disrupted and the risk of colic and founder rises ^[2].

Introducing fat

Raise fat gradually, because droppings may loosen at first, and allow at least 21 days before judging the effect on performance and feed efficiency ^[2]. Horses have tolerated mixes with up to 15% added fat without palatability or digestive problems ^[2].

A small daily dose of oil (1–2 oz) improves coat shine but does little for energy intake ^[2].

Interactions

Horses in prolonged aerobic work, or on rations above 5% fat, may need extra vitamin E ^[3]. High-fat feeds should be avoided in obese horses because of their energy content ^[4].

See also omega 3, omega 6, vitamin e, digestible energy.