Vege oil is a big no no lol
Vegetable oils in this form are poor-quality oils, all of which are polyunsaturated. This means that these oils are unstable with very poor resistance to heat and/or light. They easily release free electrons which are the culprits in free radical damage. The resulting cell damage is implicated in cancer, heart disease, and other chronic diseases related to aging and unless you buy organic many corn and canola crops are genetically modified as well.
Try a high Quality Racing oil made for race horses they are very high in Omega 3.
Or feed sunflower seeds. Oils in horse diets