CONTINUING EFFORTS TO MORE EFFICIENTLY USE LABORATORY ANIMALS
Scientists continue to expand their knowledge and improve their techniques to use the fewest animals as efficiently and humanely as possible. This approach is called the “3Rs” and was created in 1954, when the Universities Federation for Animal Welfare (UFAW) hired two young scientists to produce a report on experimental methods. UFAW, founded in 1926, had already produced the first Handbook on the Care and Management of Laboratory Animals in 1947 when it hired William Russell, a zoologist, and Rex Burch, a microbiologist, to carry out a systematic study of the advancement of humane techniques on laboratory animals. Sir Peter Medawar, who was later to receive the Nobel Prize, supervised the project. Russell and Burch visited laboratories throughout the United Kingdom for 2 years and in 1959 published a book titled The Principles of Humane Experimental Technique, which introduced the concept of the 3Rs—reducing, refining, and replacing animal use.
Russell and Burch recommended REDUCING the number of animals used in experiments to the minimum number required to obtain statistically relevant data, REFINING procedures to minimize pain and distress in experimental subjects and provide for their well-being based on their behavioral needs, and REPLACING experiments involving whole animals with in vitro models like tissue and cell culture when possible. They based these recommendations on data acquired in the course of their study, and they predicted that implementation of the 3Rs would enhance the scientific value of experiments.
Russell and Burch stated, “We assume that experimental biologists are only too happy to treat their animals as humanely as possible.” They further stated, “The central problem then is that of determining what is and what is not humane, and how humanity can be promoted without prejudice to scientific and medical aims. We must begin by examining the concept of humanity (or inhumanity) as an objective assessment of the effects of any procedure on the animal subject.”
Though it took nearly 30 years for Russell and Burch’s work to receive the attention it deserved, the 3Rs are now being practiced in laboratories throughout the world and have been incorporated in animal care legislation in the United States and the European Union.
the 3 Rs in action
Chris McNickle worked in animal hospitals for more than 20 years before she came to the National Institutes of Health (NIH) as an animal care technician. McNickle’s background in animal care helped impart not only an understanding of the ways that individual animals and different species react to illness but also “a compassion for the animal,” she says. Viewing her role as that of “patient advocate,” she says that her job in the laboratory is to “support the animal, watch the animal, and to try to improve the care of the animal.” She strongly believes that collaboration and respect among scientists, veterinarians, and veterinary technicians results not only in higher standards of animal care but also in more effective and productive science. • McNickle points to a recent 8-month study at NIH as a model of the type of research program in which careful attention to animal well-being and teamwork among veterinarians, animal care technicians, and scientists produced the maximum scientific benefit. The human benefits of this study are great—a magnetic resonance imaging (MRI) technique that is able to diagnose a heart attack instantly. • The project was a collaborative effort from the start, she notes, and was instituted when a veterinarian, Dr. Victoria Hampshire, identified two different researchers who were both using dogs to study the flow of blood through the heart attack-damaged arteries. Dr. Hampshire got the two researchers together, and they determined that, though it was not possible to REPLACE the dog model with an in vitro culture system (it is not possible to simulate a heart attack in a laboratory dish), they could get the information they both needed from the same set of dogs and thus REDUCE the number of animals used in the studies. • McNickle points out that it is crucial to recognize that laboratory animals have many of the same responses and symptoms as people, and they need to be provided with the same level of support. Thus, a team of veterinarians and technicians REFINED previous care procedures by instituting 24-hour critical care for the dogs in the study, similar to hospital intensive care units for heart attack patients. • Human patients also benefit from close monitoring of experimental animals and round-the-clock attention to their needs, McNickle says. Many of the drugs used to care for these dogs are the same as those used in human heart attack patients. She points out that by understanding what drugs and dosages cause side effects like nausea in the dogs, doctors are better able to treat human heart attack patients. “We’re better able to determine the dosage that will produce the maximum healing benefit with the least side effects,” which ultimately is the goal of all animal research.