2. B Vitamins The B vitamin complex, which includes B1 (thiamine), B2 (riboflavin), B3 (niacin), B6 (pyridoxine), B12 (cobalamin), and folic acid, is crucial for energy production, brain function, and cell metabolism. Small breed dogs benefit from B vitamins through a diet rich in meat, fish, eggs, and whole grains. These vitamins help in the proper functioning of the nervous system and reduce the risk of neurological disorders.