The Face of Vivisection is a Mouse

By Sue Leary

AV Magazine Spring 2006, The Face of Vivisectin is a Mouse

The reality is that people are deeply divided in their opinions when it comes to how rats and mice are regarded. Are they adorable children’s book and cartoon characters, welcoming us to Disneyland? Or are they scurrying spoilers of food and a public health menace? Are they the promise of reversing every known tragic human condition, or are they the victims of science? Or are they just, well, themselves? Ultimately, there are two things you need to know about mice and rats used in research: 1) They are not afforded even the minimum protections of the U.S. Animal Welfare Act and 2) They comprise nearly all of the animals used in modern research.

Second things first

“But there are laws to protect animals in research, aren’t there?” is a familiar assumption. Technically, there is a federal law called the Animal Welfare Act (AWA), and by its original design and subsequent amendments through 1990, it was intended to afford basic protections for animals in laboratories, while not interfering with “essential research.” But there is one huge loophole: it doesn’t cover 95 percent of animals used in laboratories. Why not? The answer is actually very simple: defenders of research using animals have been determined and effective in resisting efforts for government accountability, transparency, and oversight. An example is the overwhelming support of the biomedical community of the Helms amendment, which permanently excluded birds, rats, and mice from coverage under the AWA. Like virtually every other industry you can name, the animal research industry’s strong preference is for self-regulation, and, in effect, that is what it has.

The first question: how many?

One of the key pieces of information that researchers are able to keep private as a result of no regulation is how many birds, rats, and mice they are using. Of course, individual institutions have a pretty good idea because they will track them in computerized databases so they can bill per diem housing costs to the various grants. Veterinarian and author Larry Carbone feels confident with an estimate of 80-100 million rats and mice in 2002 alone, certain that the annual number will continue to grow along with the field of genetic engineering.

Where are they?

It is hard to believe that institutions can hold that many animals, even if they are crowded together. But that is part of the appeal of mice for research. Their housing is compact: the ‘shoebox’ is a plastic container that slides into vertical racks so that something that is not much bigger than a bookcase can house hundreds of mice. That means that in a single room, there can be thousands, and a building can have tens of thousands. The big universities with extensive biomedical research programs can have hundreds of thousands of mice and rats pass through their doors every year.

The modern versions of housing racks are plugged into ventilation and watering systems, so the caretakers don’t spend time interacting with individual mice on a daily basis if they are not being used in an experiment. Design and sale of laboratory housing for animals has become a big business with its own magazines and conferences. Vendors conduct research to address bio-containment, optimum rates of airflow, disposal of waste, and lighting systems (mice are nocturnal).

Where is the harm?

“A commonly used method [to measure pain] is the hot-plate test in which a rat or mouse is placed on a plate preheated to 122 degrees F to 131 degrees F. A paw-licking response is measured.

Methods and Welfare Considerations in Behavioural Research with Animals, Report of a National Institutes of Health Workshop (2002)It might appear that there is a lot of attention to the daily life experience of each animal, and there has been a significant growth in awareness in the last 30 years. Trends toward social housing, providing nesting material, ‘mouse houses,’ activity objects, and food treats, and away from wire floors, overcrowding, and handling by untrained staff, may be only sidestepping the overarching problem, however: mice and rats in laboratories all come to harm in the end.

In a report issued by the Nuffield Council on Bioethics , a number of areas are cited as a potential “source of harm” for animals captive in laboratories. They include: “breeding [including disruption of weaning and disposal of newborns who are not required in the study; e.g., only one sex is being studied, but both are born in a litter]; transportation; housing; husbandry and care; handling; restraint; identification [methods: e.g., toe-clipping, ear notching]; adverse effects of the procedures (e.g., nausea from toxic compounds, discomfort and pain from induced syndromes, natural and experimental infections); and euthanasia.” The polite and proper language may mask the severity of the problems, but it provides some idea of the wide range of situations that make mice and rats so vulnerable on a daily basis. The simple routine act of drawing blood can be perilous and painful for a mouse.

What is natural?

Some who use animals in laboratories cling to a justifying rationale that the mice and rats they use were bred for this purpose; are hundreds of generations removed from their natural born ancestors; and are therefore content with laboratory life. It is true that long before genetic engineering, there surely was selective breeding for animals who are docile and, to some extent, tolerant of laboratory conditions. But if there is any doubt that the average white rat or mouse is not comparable to their natural counterparts, one video has neatly put that doubt to rest. It’s available for free viewing online at www.ratlife.org and is quite amazing.

The filmmaker released a small group of white rats bred for the laboratory into a traditional English barnyard. Within minutes, they were engaged in a wide range of completely natural behaviors, including an impressive hiding response as a hawk passed far overhead. They gathered food, burrowed, nested, fought, mated, gave birth, and generally did rat things as easily as you could imagine, all of which was recorded over a period of many months.

What is not natural?

“I suspect Mrs. Helms would have a word or two for me if I forgot to phone the exterminator upon finding evidence that a mouse has taken up residence in our basement. Alas, extermination remains the fate every year of hundreds of thousands of rodents that have not found the relative safety of a research laboratory.”

U.S. Senator Jesse Helms, February 12, 2002No article about the use of mice and rats in research could be complete without mentioning genetic engineering (GE). It is the reason why numbers of mice used in research are growing. Sequencing of the mouse (mus musculus) genome was completed and published in 2002, and since then, ‘discovery science,’ with experimenters approaching projects with a ‘what if we tried this’ attitude, has been a juggernaut. The novelty has been compelling for scientists all over the world, and the published papers have put many a career on tenure track.

Of course, scientists’ preference for mice goes back farther than 2002. Jackson Laboratory in Maine, which is the granddaddy of genetically engineered mouse breeding, started in 1929. Their mission was traditional breeding, in order to develop mice as models for human disease. Today, their web site (www.jax.org) is wholly dedicated to assisting researchers sort out the strains available—nearly 3000—and placing orders for mice literally stored as frozen embryos with particular genetic profiles. They are thawed, surgically implanted into surrogate mothers, born, tested for the desired traits, and shipped out at the desired age.

Today, a blur of terms—knockouts, gene expression, cloning, and the like—pepper the media’s description of GE research. They confound the layperson, and do not give much of a hint of the price animals pay. One analysis cited in The Ethics of Research Involving Animals was based on reports regarding genetically modified mice made to the Danish Animal Experiment Inspectorate in 2002. They found that “21 percent of strains were reported as experiencing minor discomfort, 15 percent experienced severe discomfort, and 30 percent suffered increases in mortality and susceptibility to disease.” In other words, as a result of their inherent genetic abnormalities, their suffering is built in before an experiment even begins.

Even though years of testing chemicals in animals has demonstrated literally fatal flaws in extrapolating animal data to human experiences, some scientists want to start incorporating even more animals into chemical testing regimens, with the rationale that utilizing genetically engineered animals will produce more relevant results. AAVS and Alternatives Research & Development Foundation instead advocate moving decisively toward alternatives to animal testing, with an emphasis on replacing animals altogether.

The invisible hand

There are powerful influences that advance and perpetuate the use of genetically engineered mice in research. A network of repositories is supported by the National Institutes of Health (NIH). Animals are considered “research resources,” and centers have been established with names like “Mutant Mouse Regional Resource Centers” and the “Rat Research and Resource Center.” An illuminating journey around the website http://www.mmrrc.org will show your tax dollars at work.

The future for animals

“More than ever, laboratory animal medicine is becoming mouse medicine, with the welfare challenge for veterinarians of treating hordes of tiny near-identical subjects as individual, sensitive patients with lives of their own.”

Larry Carbone, What Animals Want, 2004The extent of mice and rats used in research is vast. Against this backdrop, it is a daunting position to be a defender of mice and rats.

However, the principles of alternatives as preferable to animal use have gained a foothold in the world of science. Large numbers of mice and rats will be spared in the near future with the changeover to alternatives in particular methodologies (such as production of monoclonal antibodies) and specific tests (such as acute toxicity). On a parallel policy track, it will help if the U.S. gets in synch with other countries to at least provide meaningful oversight of animals in laboratories. That will close the loophole for companies that conveniently choose to operate outside the Animal Welfare Act simply by restricting their use to birds, rats, or mice.

Leary, Sue. (Spring 2006). AV Magazine. Pages 2-3.

Print View

Web ViewText Size: