Raw food is best, but failing that, home cooked food is better than commercial pet foods which contain all sorts of rubbish. I wouldn't worry about vitamins and minerals as I think a healthy mix of meat and veg plus scraps is far more balanced than the stuff we're encouraged to buy based on propaganda from the very lucrative pet food industry.
Nor would I take advice on feeding pets from a vet; that is not their field of expertise and they are pressurised by pet food companies to promote and sell their stuff. Many of these have very dubious ethical credentials, testing their products on laboratory animals in very cruel ways and killing them when they've finished. If you look into it the industry is totally corrupt.
My breeder friend used to feed her dogs on sheep's heads (cooked). Seems like an excellent idea to me, uses up waste bits so that no extra animals have to die just for pet food. I'm not sure you can still get them though. The same person fed her cat on lights (which I believe are lungs) and that, supplemented by locally caught (by the cat) wildlife seemed to provided everything the cat needed.