In the 1960s, LIFE was America's single most important general weekly magazine, its photo-essay formula catering to a middle class constituency of millions. By the halfway point of that tumultuous decade, readers were accustomed to seeing searing and unpleasant images of a changing nation, one racked by civil unrest and entangled in a bloody war in Southeast Asia. But when LIFE's February 4, 1966 issue landed on newsstands and in mailboxes across the United States, with the cover's warning "YOUR DOG IS IN CRUEL DANGER," tens of millions of readers became acquainted for the first time with another kind of searing unpleasantness—the thriving commerce of unregulated dealers who supplied animals to America's laboratories for research, testing, and education.
Unti, Bernard, "‘Concentration Camps for Lost and Stolen Pets’: Stan Wayman’s LIFE Photo Essay and the Animal Welfare Act" (2007). LAWS AND LEGISLATION. 12.