The Humane Society of the United States has a point to make. “If just one of every five Americans wanting to add a cat or dog to their family in the next year adopted from a shelter, not one...

Anais Orantez holds out a blue toy for Luna, a 2-year-old brown-and-white Rottweiler mix, in the outdoor area of the Pima Animal Care Center. Locked eye-to-eye, Anais throws the ball, but 85-pound Luna...