Spinal cords, marrow, organs (especially brains) tend to be very nutrious in fact. When given a choice, most wild animals will preffer what we call the waste.
There is a theory that falconry developed in part because birds of prey will first eat the nutritious parts of prey (i.e. the spinal cords, marrow, organs, etc.) leaving the muscle for the very last. Since humans largely prefer the muscle, it forms the basis for a lovely friendship.