The delicate structure of the horse's legs and hoofs makes theses areas easily prone to problems. Of all the hoof problems a horse can suffer from, laminitis is the most worrisome.
The passive vascular congestion seen during laminitis in horses is thought to be mediated by chemicals produced from the cell membrane in response to either metabolic or physical irritation. This painful condition causes the separation of the sensitive lamellae serving as a bridge between the pedal bone to the inner hoof wall. The severity of the process depends on the amount of inflammation, the degree of blood flow reduction, clot formation and the amount of mechanical stress superimposed on the lamellae.
The above mentioned pathological changes are basically mediated from potent chemical mediators derived from the omega-6 fatty acid family. Elevated levels of omega-6, at the expense of omega-3, result in an eicosanoid precursor pool dominated by one main omega-6 family member, arachidonic acid. Arachidonic acid is the building block for prostaglandin E2 and leukotrieneB (LTB4). These two substances activate pro-inflammatory reactions producing swelling, heat and pain in the afflicted area. These mediators are then capable of destroying key components of the lamellar attachment. This may lead to painful tearing of the support structure suspending the pedal bone within the hoof. If laminitis is not treated promptly, it can lead to a final downward rotation of pedal bone as a consequence of its separations from the lamellae.
We know the predisposing factors for the development of laminitis in horses include any inflammatory processes. Usually these are relation to the gastrointestinal tract, reproductive organs (metritis, retained placenta), respiratory system (pleuropneumonia), endotoxemia and even traumatic factors such as prolonged or excessive weight in one or more limbs.
Dr Gerard Hornstra, Professor of Experimental Nutrition at the Maastricht University explains, EPA and DHA inhibit eicosanoid synthesis from arachidonic acid and cytokine production from monocytes/macrophages. Although omega-3 EPA promotes the formation of prostaglandin E3 and leukotriene B5, these eicosanoids are far less active as pro-inflammatory agents than the corresponding derivatives of arachidonic acid. It is then thought the active and potent anti-inflammatory mediators derived from omega-3's EPA and DHA will reduce the risk of exacerbated inflammatory responses when any predisposing factors develop. In addition they have a positive regulatory effect on the vascular bed and their pro-coagulant effects are also much less active.
Increase supplementation of the horses' diet with omega-3 essential fatty acids results in a partial and progressive substitution of omega-6 derivatives in the cell membrane. As the amount of omega-6 decreases and the amount of omega-3 increases, the risks of exacerbated inflammatory responses are reduced.
Many testimonials exist from horse people about the radical improvement of horses with chronic founder after a few weeks of supplementation with omega-3 essential fatty acids with EPA/DHA.