Supplement Question

I was wondering if corn oil, olive oil or peanut oil would be safe to add to a cat's diet for coat supplemtation?

I would think that an Omega-3 Fish oil would be much healthier and still achieve a good coat.

Ditto that -- I've tried it and it works great.

I use olive omega 3, 6 and 9, flax is another good one.. fish is fine but only covers a potion of the problem

You need to make sure that you provide omega3 and omega 6 fatty acids in the right proportions or they won't do any good. Most good quality cat foods already do this, so first of all, make sure your cats are on a good diet. If their coats still look like they need some help- I would look for a supplement designed for pets.