BENTONVILLE, Ark. – Walmart announced it will be opening up dozens more veterinary clinics in its stores and launching its first online pet pharmacy, hoping to lure more U.S. pet owners who are spending billions of dollars each year on their dogs and cats.

The retail giant already operates 21 veterinary clinics in its stores across six states, but over the next 12 months it will growth that number to 100. It will start the expansion by opening nine new clinics in the Dallas-Fort Worth area later this month and into June. There, pets can receive vaccines, care for minor illnesses and other routine exams.

Walmart also will launch an online pet pharmacy, WalmartPetRX.com, rivaling PetSmart’s e-commerce business, Chewy.com, which also has an online pharmacy unit. Walmart said its website will offer low-cost prescriptions for dogs, cats, horses and livestock, from more than 300 brands.

Walmart has seen a roughly 60% increase in the number of dog- and cat-related health-care items sold on its website over the past year, the company reported.