What a dog eats at Each life stage has a powerful effect on their growth, strength and total well-being. The OPTIMUM range is developed in association with the Waltham Petcare Science Institute, a world leading authority in pet care and pet health, so you can be confident that your pets receive the best in pet nutrition. OPTIMUM products deliver balanced nutrition and flavour variety that your dog will love with a selection of wet and dry products tailored to every life stage. GRAIN FREE FORMULA NO ARTIFICIAL FLAVOURS, COLOURS OR PRESERVATIVES The unique OPTIMUM dry product formulation contains high levels of chicken, providing a natural source of arginine. Scientific studies have shown that arginine in conjunction with vitamin E help to maintain healthy blood circulation and cardiac function..