PetSmart, America’s largest pet store chain, is considering an expansion into in-home services, including dog walking and setting up home aquariums, in an effort to distinguish itself from retailers such as Wal-Mart.

PetSmart is in the early stages of developing ways to provide the services, according to the retailer’s new chief executive, Robert Moran. Wal-Mart is targeting the market for pet goods, putting pressure on PetSmart as shoppers hunt for bargains in the recession.