If you are caring for a Saint Bernard which usually weigh from 170 to over 200 pounds and has a powerful, strong and muscular body, of course you need to provide them with a high grade quality -dog food that holds at least 40 % of protein, moderate in fats and contains fiber. It would be best to give them two or three undersized meals a day than the habitual feeding which comes ones or twice a day since they are prone for bloating. Always try to be consistent with their feed to maintain their physical condition.