River Valley Mastiffs

River Valley Mastiffs, mastiffs in Kennewick, WA, Benton County and the Tri-Cities near Pasco. Rebecca Davis has guided their work for many years with close attention to lineage, structure and temperament.

They follow breed club guidelines and carry out health testing for hips, elbows, eyes and cardiac function as well as thyroid evaluation. Puppies are born and raised inside the family home with daily enrichment activities, gentle handling and socialization around visitors, other pets and children. Spacious yards and shaded barns offer safe, varied environments as they grow.

The breeding focus aims for calm, balanced companions suited to both family life and working roles. Recent owners have noted steady temperaments and robust builds that fit active lifestyles. Each puppy leaves with a detailed health record and guidance on nutrition, growth and training to ensure a smooth transition and confident start in its new home.