Why rats are used for scientific research all over the world

Humans and mice are not alike, but both species are mammals and are very similar biologically. Mice have long been a favorite research animal of scientists. This article will give us the answer to the question: Why are rats used for scientific research all over the world?

The “king” and “queen” of the laboratory

It is not by chance that mice and rats are called the “king” and “queen” of the laboratory. But how can rats rule the scientific world?

A recent European Union (EU) report shows that mice and rats account for 75% of animal species used in pet research, including 61% mice and 14% rats.

Next come cold-blooded species (12.4%), birds (5.9%) and rabbits (5%). This equates to 8.6 million rats used in science each year in the EU alone. If this rate were replicated globally, the number of lab rats would rise to about 75 million per year!

A study examining trends in the use of animals in science found that between 2000 and 2004, almost half of the articles published in the field of neuroscience used rats as the primary experimental subject.

Data from the US National Library of Medicine shows that more scientific papers use mice as test subjects than simpler organisms like yeast, zebrafish, fruit flies, and roundworms—3 times more than all of the above creatures.

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Why are rats used for scientific research all over the world?

Small and cheap

If you ask a scientist what advantages mice and rats have in an experiment, the answer will be: they are small, cheap, kind and easy to interfere with.

Rats are not covered by strict animal rights laws like larger animals such as monkeys, dogs or cats. This avoids legal difficulties in the search.

The small size of mice makes them simpler and cheaper to keep in the laboratory than other species. A lab rat costs about $5, and it only takes 1/10 of that price to feed it every day.

Slightly more expensive is the common black or gray mouse, which costs between $16 and $23 and is often used as a base strain for genetic interventions.

Hamsters are similarly priced, but are primarily used in circadian rhythm studies due to their hyperactive nature and 12-hour nightly activity. The most “premium” type is a hairless mouse ($73-136). This mouse’s fur-like skin allows scientists to easily monitor the healing process and perform tumor transplant experiments on mice to observe the growth of cancer cells.

In particular, all mouse breeds can be ordered in bulk online or by phone with next day delivery.

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Easy to train and breed

Rats are easy to train and well suited for psychological experiments. The rat’s neural network is very similar to that of humans.

In the 19th century, various animals were used as hosts in scientific research: sheep, raccoons, pigeons, but also frogs, birds, horses. The rat family is the “universal key” to unlock all the mysterious doors of medicine, be it cancer, diabetes, depression, post-traumatic stress disorder or any other disease. any disability or impairment that a person may suffer from.

Common ancestor with man

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Rats have the same evolutionary ancestry as humans. The mouse genome is very similar to that of humans. Most mice used in medical trials are closely related, so they have similar genomes, which helps the results of medical experiments to be more consistent. Laboratory mice should be at least of the same pure breed. Also, the mouse’s small size allows scientists to easily handle it in the laboratory.

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How to treat rats in the laboratory

The mouse, the most famous laboratory animal, has helped man achieve many scientific achievements. What this animal goes through every day in the laboratory is largely unknown.

Before scientists are allowed to “work” with them in the lab, they must be trained in ethical behavior and animal handling. Processing regulations vary by country. In Canada and Europe, scientists are under the control of a national regulatory body. In the United States, they must follow each agency’s individual regulations and the National Institutes of Health’s general guidelines.

Most universities offer training courses on how to handle rats to minimize stress and pain during the experiment. The application process is updated annually to reflect the reality of people’s understanding of rats. After a 2010 study published in the journal Nature claimed that “grabbing rats by their tails scares them,” researchers changed their approach by feeding mice through a tube or holding them by the hand to bring them into the test area. It is interesting that now laboratories in different parts of the world have banned the carrying of rats by the tail.

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To conduct an experiment on mice, scientists must submit an application explaining why their work requires the use of animals. Applications are reviewed based on three principles: Limit the number of animals used, replace animals where possible, and improve practices to improve animal welfare. For example, a scientist must ensure that he is skilled in keeping mice in the laboratory.

Although experimental mice had different genes than wild mice, they still had many of the same instincts. Typically, rats in laboratories are kept in equal numbers in cages as large as a shoebox or larger. Although keeping rats together to support each other fulfills the need for flocking, most laboratories do not have opportunities for habitat diversification. Living in a cage prevents rats from engaging in natural behaviors such as digging, climbing, or standing. Reducing the need for nature can cause stress in rats and affect research results.

To get the best results, the nature of the mouse needs to be taken into account when designing the experimental environment, the researchers say. On the way to using mice to better understand humans, researching mice to treat human diseases, deliberately altering the biological properties of mice, or vice versa, will lead to failure or ineffectiveness. i would like

In addition, the process of transferring experiments from mice to humans was also carried out very carefully. In addition to theoretical studies, scientists must also clinically test the new herbal medicine on two other groups of animals: a group with the body dimensions of mice and a group with the size and characteristics of humans (such as mice, pigs, dogs or monkeys). ) and then test them on humans.

According to US drug manufacturers and researchers, only one of the 250 compounds tested in animals has been tested in humans. The entire process for the approval of this drug takes 10-15 years. The irony is that despite this delay, many drugs and procedures that work in mice do not work in humans.

Regardless of the success or failure of the experiment, one thing is certain: after the experiment is over, the mouse will be “at the end of its life”. It is estimated that 100 million mice are “sacrificed” for scientific research in American laboratories every year.