D-biotin, commonly known as biotin or vitamin B7, is a water-soluble vitamin that is used in dog food. Its primary function is as a dietary supplement to support metabolic processes in animals. In dog food, d-biotin serves as a source of this essential nutrient, which is involved in the metabolism of fats, carbohydrates, and proteins.D-biotin, commonly known as biotin or vitamin B7, is a water-soluble vitamin that is used in dog food. Its primary function is as a dietary supplement to support metabolic processes in animals. In dog food, d-biotin serves as a source of this essential nutrient, which is involved in the metabolism of fats, carbohydrates, and proteins.Read More