The role of living organisms and animal models in scientific research has a long history. From Aristotle’s first observations on biology to the modern era of pharmaceutical research, the use of animals in research has always been present in science.
Even in popular culture, no image of a lab is complete without little white mice. As another example, most people remember classical conditioning as a story about Pavlov’s dog more than anything else.
The need for living organisms in science and research continues to this day, but there is much more attention focused on how animals are treated.
In Drug Discovery the use of animals in research is unavoidable. Looking into a potential new treatment requires a complete understanding of its toxicity, safety, and efficacy. Finding all that information requires an understanding of all the effects on the biological system. In other words, it requires an animal model and careful adherence to the 3Rs principles.
Experimental procedures and newly found molecules need to be thoroughly tested before humans are added to the equation. Animal models act as a reliable stand-in that allows for the research to continue, providing as much information as possible about how new treatments could affect future patients.
The goal of drug development is to help future patients, but there is always a focus on the proper treatment of the animal models used in preclinical research.
Over the last century many organizations, guidelines, and laws have been drafted and put into effect concerning the treatment and care of animal models. One of the strongest guiding principles for the scientific community can be found in the three Rs (3Rs).
The 3Rs are a series of formalized guidelines that set broader goals for the more ethical use of animals in research. They emphasize not only eliminating any exposure to harmful situations, but also actively encourage new laboratory methods and practices.
The 3Rs are structured around allowing for science to continue while ensuring the safety and well-being of animal models. With a strong emphasis placed on making an effort to ensure the use of animals in research is absolutely necessary, following the 3Rs leads to designing better tests and assays for more effective research that guarantees more relevant information.
When the use of animals in research cannot be avoided, as is often the case in biomedical science, the 3Rs ensure ethical treatment and encourage the use of alternative models.
The Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC) is a well-known non-profit organization dedicated to promoting the ethical treatment of animals in research. The AAALAC created a voluntary accreditation and assessment program for institutions around the world in order to meet specific standards regarding the use of animal models and defining what is not considered an animal in research.
In order to receive accreditation, institutions must meet local regulations and regional laws while also following the standards explained in the Guide for the Care and Use of Laboratory Animals. With a neutral international standard, the AAALAC helps ensure animal welfare on a global scale as research continues.
Transparent and internationally agreed standards help science move forward while ensuring better treatment of animal models.
The increased focus on the ethical treatment of animals in research has led to a significant uptick in the need for alternative animal models. Zebrafish have emerged as a prime choice that sits at the crossroads of the 3Rs. The inherent traits and natural behavior of the small vertebrate fish allow for more ethical research with an animal model that is highly homologous to humans.
Zebrafish embryos are completely transparent and allow for direct observations without harming or injuring the animal. Furthermore, most organs are developed by day five post-fertilization and according to a European directive, these fish are not considered animals when experiments are performed within those first days of development.
The fast pace and intense competition of the pharmaceutical industry creates strong incentives to quickly find cures and understand emerging diseases. The battle against time requires large sample sizes that are cost effective in order to stay in the race.
Maintaining Zebrafish also comes with benefits for any experiments looking to ensure reproducibility. With hundreds of eggs maturing in just a few days, the small fish are well adapted to large scale experimentation without altering their natural behavior.
Zebrafish provide an ethical alternative to traditional animal models while also allowing for faster testing at a larger scale.