Coupon Codes, and Deals of the Day at Chewy:
https://www.chewy.com/deals/todays-deals-2723
Groupon is an online platform that offers coupons, cashback on purchases, and group deals to consumers (here, with pets!):
https://www.groupon.com/goods/dog-supplies
Great deals on general pet supplies, and dog apparel, at Retail Me Not: