Walmart is launching its own line of ultra-premium dry dog food to compete directly with specialty pet product retailers such as PetSmart and Petco.

The new brand, Pure Balance, is an expansion of Walmart's Ol' Roy brand of dog food that is currently sold and is expected to appear on store shelves in the coming weeks. The Pure Balance line will include a chicken and brown rice variety and a lamb and brown rice variety, which will be sold in 30-, 15- and 5-pound bags. Walmart says the new brand contains no chicken by-products, as well as no soy, wheat or corn additives, artificial colors and preservatives.