HOME / pepper: The stolen dog that changed American science.

Brown Dogs and Red HerringsOr, why we no longer experiment much on dogs.

By Daniel EngberPosted Thursday, June 4, 2009, at 6:36 AM ET

At the turn of the century, animal activists organized their campaigns around research dogs and cats, but science was already moving in a new direction. Mendel's ideas had been rediscovered in 1900 and the term genetics coined in 1906; the new science of heredity created a sudden need for organisms whose exact ancestry was known and controlled. Within a few years, the perception and practice of biomedical research had begun to diverge: While humane societies were worrying about missing pets, researchers were shifting to a new set of standardized, purpose-bred laboratory organisms—the rat, the mouse and the fruit fly.

The standardization of laboratory animals reflected the growing influence of industrial engineering in America. Under the new paradigm, research organisms could be seen as a sort of raw material for use in a knowledge assembly line. Just 10 or 20 years earlier, a physiologist might have conducted his experiments on a variety of species—frogs and rabbits, for example, or dogs, horses, and baboons—to show that a finding could be generalized across the whole of creation. Now, whatever could be demonstrated in a rat or a mouse was assumed to be true of a dog, a horse, or a human. The growth of statistical science also changed the nature of laboratory work: Now it was advantageous to increase your N by repeating an experiment as many times as you could on as many animals as were available.

Biomedical science became even more industrialized during the postwar period as government money flowed through the pumped-up National Institutes of Health. Grants officers realized that animals could be most efficiently distributed if they were churned out in large numbers at a few, centralized locations. Meanwhile, the organisms themselves had begun to be packaged as commercial products: In 1941, the breeders at the Jackson Laboratory in Maine received a patent on their line of "JAX Mice" research animals; a year later, the Wistar Institute in Philadelphia trademarked its own line of "WISTARATs."

Experimental dogs had been well-suited to the old-fashioned, artisanal mode of inquiry—William Harvey cutting open a heart, Christopher Wren pumping a vein full of wine, Richard Lower transfusing blood with a chain of quills. But as an instrument of modern science, they were starting to look obsolete. The economics of breeding dogs were one problem: In 1965, the year Pepper was taken, a dog could be raised and maintained in a research lab for about 70 cents per day. At that rate, though, it would cost more than $250 to produce a single, sexually mature animal. A stray with uncertain heritage could be had from a dealer for just $15, which explains why hospitals were buying dogs like Pepper to begin with.

That's not to say dogs didn't have their niche in biomedicine. Medical schools, in particular, made ample use of them for education and research in surgery and cardiology. And many of the landmark studies on anemia, diabetes, hemophilia, and cardiothoracic surgery used dogs. But by the time of Pepper's death, there was already a move toward replacing canines on the operating table with a brand-new model organism—the miniature pig. The hairless and docile Yucatan mini-pig had been introduced to the United States in 1960, and the University of Missouri opened a dedicated miniature swine production facility in 1965.

Graph of Lab Animals Counted Under Animal Welfare Act. Like dogs, miniature pigs were big enough to operate on but not so big that they couldn't be housed and handled. Porcine skin turned out to be so similar to our own that it could be used as a temporary patch for burn patients and a vehicle for the study of melanoma. Mini-pigs were also excellent subjects for the study of cardiovascular fitness, atherosclerosis, obesity, and diabetes.

A total of 260,000 dogs were used by U.S. labs in 1967, the year that Pepper's dog-napping law took effect. Over the next four decades, that number would drop by almost 75 percent. Surely some of that decline has come in response to continuing pressure from animal-welfare activists. (Research on miniature pigs isn't as likely to draw angry protests.) More significant, though, was the fact that science itself had changed.

The Laboratory Animal Welfare Act passed in 1966 gave some protection to a small number of species in limited settings. But the animal rights activists, emboldened by success, were soon able to broaden its scope. The first major amendments arrived in 1970; from then on, the law would be known simply as the "Animal Welfare Act," and its reach extended to circuses, zoos, shows, and wholesale pet dealers. The laboratories, too, had new responsibilities: Where the 1966 version had applied only to research holding facilities—with cage-size and feeding requirements, for example—now the experiments themselves were subject to humane standards, including pain management whenever possible. But what might have been the most significant change to Pepper's law was a broadening of the very definition of the word animal. Instead of protecting only the most lovable critters—dogs, cats, nonhuman primates, rabbits, hamsters, and guinea pigs—the new law could be taken to apply to every other warm-blooded animal used in the lab.

That dramatic mandate was handed over to Dale Schwindaman, a federal veterinarian who had been summoned to Washington four years earlier to help draft the original regulations related to Pepper's law. It hadn't been easy for the Department of Agriculture to enforce the original act; now Schwindaman had to figure out how to address a raft of new responsibilities.

The numbers were grim. A laboratory-animal survey conducted by the National Academies of Science found that the original covered species—the cute animals—made up just 7 percent of the total used in U.S. labs. In addition to the 260,000 dogs, there were 100,000 cats and 800,000 hamsters. But there were 30 million rats and mice. "The job was too big," Schwindaman says. Full coverage of warm-blooded species would have given the USDA the obligation to supervise every last junior college that used rodents or chick embryos for teaching. "The math just did not allow it. … We couldn't use the National Guard to make all of these inspections. We didn't have the force."

With Schwindaman's help, the USDA put in place in 1972 a special exemption for rats, mice, and birds, allowing scientists to treat them however they saw fit—in cages of any size, in experiments with any degree of pain and suffering. That exemption remains in force, despite Schwindaman's later attempts to overturn it. To this day, 95 percent of the animals used in research labs receive no federal protection whatsoever under the Animal Welfare Act.