Vitamins are required for growth and maintenance. Vitamin deficiencies can cause a variety of health problems; however, they can also be dangerous in large quantities. Vitamins dogs require include A (carrots, pumpkin), B vitamins (liver, green vegetables, whole grains), C (fruits and vegetables, organ meat), D (liver, fish, beef), E (leafy green vegetables, liver, bran, plant oils), K (fish, leafy green vegetables, fish), and choline (liver, fish, meats, egg yolks).