High quality oils are rich in certain vitamins and oligo-elements, as well as being mechanically supportive to the digestive system. The use of oils as feed supplements is standard procedure in many training yards and studs. It is of great importance that the oils be of high quality if they are to be rich in certain vitamins and oligo-elements, which are easily assimilated and used by the horse. In addition oils are mechanically beneficial to the digestive process. Cod Liver Oil is rich in vitamins A and D, this readily assimilated oil is a valuable general aid to conditioning.