Welcome to Upets.id! Vitamin that is important for your dog and cat: Vitamin K. Important for blood clotting processes and a source of bone protein. Vitamin B1. Required for carbohydrate metabolism processes, also to activate ion channels in nerve tissue. Vitamin B2 and B3. Important for enzyme function. Vitamin B6. Important for glucose formation, nervous system function, and red blood cell development. Vitamin B6 is also needed for hormone regulation. Folic acid. Important for metabolism and protein synthesis. The vitamins above will be adequately supplied in the bodies of dogs and cats if you choose quality food correctly. Quality dog and cat food is formulated with a balanced and complete content of vitamins and minerals, and certainly in accordance with the provisions of the authorized animal feed supervisory association. Usually, per serving of a balanced diet contains 40 nutrients in sufficient quantities needed by dogs/cats. So generally, additional vitamins are not needed if the dog has been given quality dog food, except when there are health problems that can interfere with nutrient absorption.