Whether or not dogs need a multivitamin depends on several factors, including their diet, age, and overall health. Generally speaking, dogs that eat a well-balanced diet that meets their nutritional needs do not require a multivitamin. A balanced diet should provide all of the essential vitamins and minerals that dogs need to maintain good health.
However, there may be certain circumstances in which a multivitamin could be beneficial for your dog. For example, older dogs may have decreased nutrient absorption and may benefit from a multivitamin to help meet their nutritional needs. Dogs with certain health conditions, such as liver or kidney disease, may also benefit from a multivitamin under the guidance of a veterinarian.
It's important to keep in mind that multivitamins are not a substitute for a balanced diet and should only be used as directed by a veterinarian. Over-supplementation with vitamins and minerals can be harmful to your dog's health. If you are unsure whether your dog needs a multivitamin, it is always best to consult with your veterinarian.