RED DEER – Feeding fat to horses is a common practice to grow a more luxurious coat, but modern research shows fat carries other nutritional benefits as well.
“We have found up to 20 percent of their total diet by weight can be fat without any ill effects,” said horse specialist Lori Warren of Colorado State University.
“Usually six to 10 percent is where we try and work in the range that seems to have the most benefit,” she told an Alberta horse breeders conference in Red Deer on Jan. 11.
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There are different types of fat based on chemical composition. Saturated fats turn solid at room temperature while mono and polyunsaturated fats remain liquid. Polyunsaturated fats are unstable and may go rancid quickly so purchases must be made wisely to ensure quality remains. If feed spoils, horses may refuse to touch it.
Most fats contain a mixture of all three types.
“The fats and oils we buy to feed our horses are not a uniform material,” she said.
“They are made up of different fatty acids that could become important in the future.”
Horses digest fat well because they do not have a gall bladder. The fat is 80-90 percent digestible in their small intestine, which is a much higher level than cattle, whose fat intake is limited to about five percent because it interferes with fibre digestion.
Many producers add vegetable oils derived from corn, canola or soybeans, but fat may also be found in feed grains such as corn, canola, flax and rice bran. These all have a fairly high percentage of polyunsaturated fats containing essential fatty acids.
Horses need a balanced ratio of fatty acids for good health benefits, including linoleic fatty acid and alpha linoleic fatty acid for good health of the cardiovascular and immune systems. The right fats may also lower inflammation.
Added fats in the diet help absorb vitamins A, D, E and K. Horses on pasture get enough of these vitamins but those kept in stables may require supplementation.
Fat adds energy because it contains more calories per pound than other sources.
Fat in the diet is a good way for thin horses to gain weight, older horses to maintain weight and hard-working horses such as Thoroughbreds to keep weight on.
Hard-working horses burn many calories, so fat may be one way to provide them with extra energy without forcing them to eat more hay or grain. Horses eat about two to three percent of their body weight per day.
“Fat is one way to add calories without adding a lot of extra feed,” Warren said.
Grain provides calories in the starch, but too much can cause diarrhea, colic and founder.
Like all new feeds, fat should be added slowly over several weeks to avoid digestive upsets such as diarrhea.
Researchers suspect increasing fat in horse diets will improve athletic performance. It spares muscle glycogen so the horse is burning less sugar. Glycogen is a carbohydrate stored in the muscle and liver. Horses tire sooner if they use too much glycogen.
Fat is stored in muscle and as body fat. Horses can store a lot of fat and then burn it off during exercise.
Using fat rather than glycogen reduces thermal loads so they do not overheat and sweat less, thus losing fewer electrolytes during exercise.
“We know it will affect their metabolism during exercise and we may help them during exercise to live up to their potential,” Warren said.
Fat also seems to improve temperament. It suppresses insulin production and because horses get less of a sugar high, they are less apt to behave erratically.
To feed fat, consider top dressing vegetable oil on rations gradually because even one cup of oil can upset a horse’s digestion. Growing horses or lactating mares could be affected the most.
Oil-rich feed such as flax or rice bran works better for finicky eaters, but a disadvantage is that rice bran contains higher levels of phosphorous.
Fat can be added to commercial grain mixes, which are generally well balanced nutritionally.
To produce a glossy coat, the horse needs a quarter to half a cup of oil per day.
To add calories for energy, up to two cups of oil per day are needed.
Two to three cups per day are necessary for enhanced performance.
Always be aware of feed sources. Feeding canola or soybean meal will not provide needed fat.
They are protein feeds in which the oil has been extracted for human consumption.
