Complex sentence: In most cow's based formulas, lactose is the main source of carbohydrates present, but lactose is not present in cow's milk-based lactose-free formulas nor specialized non-milk protein formulas or hydrolyzed protein formulas for infants with milk protein sensitivity.
Split into simpler sentences: In most cow's based formulas, lactose is the main source of carbohydrates present. But lactose is not present in cow's milk-based lactose-free formulas nor specialized non-milk protein formulas or hydrolyzed protein formulas for infants with milk protein sensitivity.