Is Fat Friend or Foe?
Kentucky Equine Research has conducted studies on feeding different fats to horses for only as long as 18 months. So it is hard to determine the detrimental effects long term fat diets have on horses. We understand the detrimental effects high fat diets have on humans, but compared to horses humans have a longer life span, so the effects fat has on the human body takes longer to have an effect and there have been intensive studies carried out on the effects fat has on the human body. As more and more horses are maintained on high fat diets for the majority of their lives, there will be more opportunity to develop a better understanding of the influence of high fat diets on the health and well-being of the horse.
Fat might be used in a horses diet to improve performance, maintain weight, improve coat and skin condition or increase the energy density of the diet. There is however already a small percentage of fat in a horses readily available diet, grass has 1-4% fat, oats can have 4-5%, and even hay has 1-3%, so having fat in the diet of the horse in not completely new to what they already consume in their everyday diet. In fact the horse digests fat better than its herbivore counterparts- cows and sheep. Horses can tolerate up to 20% of their diet as fat, although this is rarely ever fed.
When introducing fat to a horses diet it needs to be done gradually to allow digestive processes to adapt to the high fat diet, build up slowly over 7-10 days. Horses take time to adapt their digestive and metabolic processes to a higher fat diet. It takes 14 - 30 days to adapt the digestive system and a minimum of 30 days to switch on the metabolic processes in the muscle to utilise fat as an energy source in preference to glucose. It takes 3-4 months for muscles to produce aerobic energy at optimum levels using fat so it becomes obvious that the benefits of a high fat diet will not be obvious over night.