Bippa,
Ferretone is an oil and vitamin treat/supplement that comes in two brands: the original 'ferretone' from 8-in-1 brand, and Marshall brand 'furo-tone'. Both are a mix of vegetable oil, cod liver oil, and vitamins.
Ingredients: Soybean Oil, Cod Liver Oil, Lecithin, Wheat Germ Oil, Vitamin A Supplement, Vitamin D Supplement, Vitamin E Supplement, Pyridoxine Hydrochloride, Biotin, Mono and Diglycerides, and BHT and Propyl Paraben (as preservatives). 180 mg linolenic acid, 2000 mg linoleic acid, 53 mg arachiodonic acid, 1000 mg oleic acid, 1333 iu vitamin a, 100 iu vitamin d3, 10.7 iu vitamin e, 4.3 mg choline, 1.7 mg inositol, 0.4 mg vitamin b6, 17.3 mcg biotin. PRESERVATIVES USED: BHT, PropylParabin.
Some ferret owners choose to skip the commercial oil treats and simply offer fish and/or vegetable oils (or homemade oil mixes) to their ferrets. This gives them more control to choose vitamin levels, choose Omega 3 and 6 levels, avoid certain preservatives, and can also prove much less expensive. Most ferrets will gladly accept a variety of oils as 'treats'.