The history behind animal testing in research

The history behind animal testing in research

By Joseph Valenti, Biology, 2023

In the past decade, a piece of technology known as a Microfluidic Human Organ-on-Chips, or Organ Chips, has been in development for research testing. These Organ Chips are clear structures that house living cells that recreate organ and tissue structures and functions, which can be applied to test isolated interactions with diseases. Traditionally, however, the common subjects for research have been animals such as rodents. Using animals in research remains a controversial topic in recent times, but where does the root of animal testing in research lie?

The earliest recorded research involving animals trace back to the ancient Greeks, who used vertebrate animals in order to study anatomy. Using human models was discouraged, but the use of animal models was not questioned until the development of empiric schools of thought. The rise of Christianity throughout Europe led to a decline in the practice until the Renaissance, when a lone Flemish anatomist, Andreas Vesalius, began the practice of using human and animal models. His work provoked a continued use of animal testing during the Age of Enlightenment. Dueling schools of thought debated whether or not it was ethically right to use animals in research, mainly on the basis of whether or not animals felt the same way humans do. Ultimately, animal testing prevailed in this period, with advancements in the studies of physiology and toxicology used as justifications.

The earliest recorded research involving animals trace back to the ancient Greeks, who used vertebrate animals in order to study anatomy.

While debates on the use of animals in research started in the Age of Enlightenment, it was not until the mid-1800’s that these debates peaked. One scientist, Francois Magendie, became notorious for his gruesome use of animals in research. While he did provide meaningful contributions through his work, those opposing animal testing discouraged his techniques. This set the groundwork for the first piece of legislation regulating the use of animals in experiments in 1876.

Heading into the twentieth century, scientists pledged to avoid unnecessary cruelty in response to the increase in regulations. A shift towards the three Rs, replacement, reduction and refinement, took place. Many studies began to limit themselves to undesirable species such as rodents as well.

Heading into the twentieth century, scientists pledged to avoid unnecessary cruelty in response to the increase in regulations. A shift towards the three Rs, replacement, reduction and refinement, took place.

Some hold the idea that using less “sentient” animals is acceptable, but this is paradoxical considering humans use animals in order to try and model human reaction and feelings. In addition, while living vertebrates are supposed to be protected, many undesirable animals such as rodents are still used, despite the fact that rats or mice are not less biologically sentient than higher prioritized animals such as dogs or cats.

With advancing technology, the prospect of phasing out vertebrates for mechanisms such as the organ chips is on the horizon. While animal testing has provided advancements throughout history, it, along with its controversy, may become a thing of the past.

DOI: 10.3390/ani3010238

DOI: 10.1177/0162243917736138

DOI: 10.1038/s41568–018–0104–6