The experimentation on animals is a topic that is under debate and, if we delve a little into recent history, we will see that it is not something new It is a much-discussed topic both in the scientific, political and social spheres.
Since the second half of the 20th century, animal welfare has been debated, not only for experimental animals, but also for domestic animals or animals in the meat industry.
In this article on our site we will take a short tour of the history of animal experimentation, starting with its definition, thetypes of experimentation that exist and the possible alternatives.
What is animal experimentation?
Animal experimentation is the creation and use of animal models for scientific purposes, whose purpose is usually to lengthen and improve life and that of other animals, such as pets or livestock.
Research with animals is mandatory in the development of new drugs or therapies that are going to be used in humans according to the Nuremberg Code, after the barbarities with humans were committed in the Second World War. According to the Helsinki Declaration, biomedical research in humans "must be based on properly conducted laboratory tests and animal experimentation".
Types of animal experimentation
There are many types of animal experimentation depending on the field of research:
- Agrifood research: study of genes with agronomic interest and design of transgenic plants or animals.
- Medicine and veterinary: diagnosis of diseases, creation of vaccines, treatment and cure of diseases, etc.
- Biotechnology: protein production, biosafety, etc.
- Environment: analysis and detection of contaminants, biosafety, population genetics, migratory behavior studies, reproductive behavior studies, etc..
- Genomics: analysis of the structure and function of genes, creation of genome banks, creation of animal models of human diseases, etc..
- Pharmacy: biomedical engineering for diagnosis, xenotransplantation (creation of organs in pigs and primates for transplantation into humans), creation of new drugs, toxicology, etc.
- Oncology: tumor progression studies, creation of new tumor markers, metastasis, tumor prediction, etc.
- Infectious diseases: study of bacterial diseases, resistance to antibiotics, studies of viral diseases (hepatitis, myxomatosis, HIV…), parasitic (Leishmania, malaria, filariasis…)
- Neurosciences: study of neurodegenerative diseases (Alzheimer's), study of nervous tissue, pain mechanisms, creation of new therapies, etc.
- Cardiovascular diseases: heart disease, hypertension, etc.
History of animal experimentation
The use of animals for experimentation is not a current fact, these techniques have been carried out long before Classical Greece, specifically since Prehistory, evidence of this are the drawings that can be seen inside the animals in caves, made by the ancient Homo sapiens.
Beginnings of animal experimentation
The first recorded experimenter was Acmaeon of Crotona, who in 450 B. C. it severed the optic nerve, causing blindness in one animal. Other examples of ancient experimenters are Alexandria Herophilus (330-250 BC) who showed the functional difference between nerves and tendons using animals, or Galen (130-210 AD)C.) who practiced dissection techniques, showing not only the anatomy of certain organs, but also their functions.
The Middle Ages
The Middle Ages set science back due, according to historians, to three main causes:
- The fall of the Western Roman Empire and the disappearance of the knowledge provided by the Greeks.
- The invasion of barbarians from much less developed Asian tribes
- The expansion of Christianity, which did not believe in corporeal principles, but rather spiritual ones.
The arrival of Islam in Europe did not serve to increase medical knowledge, since they were against the performance of autopsies and necropsies, but thanks to them all the lost information of the Greeks was recovered.
In the 4th century, a heresy arose within Christianity in Byzantium, expelling part of the population, they settled in Persia and created the first School of Medicine In the 8th century, Persia was conquered by the Arabs and they took all the knowledge, spreading it throughout the territories they conquered.
Also in Persia, in the 10th century, the physician and experimenter Ibn Sina, known in the West as Avicenna, was born. Before the age of 20 he had published more than 20 volumes on all the known sciences, in which he appears, for example, how to do a tracheotomy.
Transition to the Modern Age
Later in history, during the Renaissance, the performance of autopsies gave a boost to the knowledge of human anatomy. In England, Francis Bacon (1561-1626) in his writings on experimentation affirmed the necessity of using animalsof experimentation for the advancement of science. At this same time many other experimenters appeared who supported Bacon's idea.
On the other hand, Carlo Ruini (1530 – 1598), a veterinarian, jurist and architect, captured the entire anatomy and skeleton of the horse, as well as how to cure certain diseases of the horse.
In 1665, Richard lower (1631 – 1691) performed the first blood transfusion between dogs. He later tried it from dog to human, but the consequences were fatal.
Robert Boyle (1627-1691) demonstrated through the use of animals that air is essential for life.
In the 18th century, animal experimentation increased considerably and thoughts against it began to appear and the firstawareness of the pain and suffering of non-human animals. Henri Duhamel Dumenceau (1700-1782) wrote an essay in favor of animal experimentation from an ethical point of view in which he said: "every day more animals die to satisfy our appetite than can be slaughtered by the scalpel of the anatomical, which does so with the useful purpose that it results in the preservation of he alth and in the cure of diseases". On the other hand, in 1760, James Ferguson created the first Alternative Technique to the use of experimental animals.
The Contemporary Age
In the 19th century the greatest discoveries of modern medicine occurred through the use of animals:
- Louis Pasteur (1822 - 1895) created the vaccines for anthrax in sheep, cholera in chickens and rabies in dogs.
- Robert Koch (1842 – 1919) discovered the bacterium that causes tuberculosis.
- Paul Erlich (1854 – 1919) studied meningitis and syphilis, being the promoter of immunology.
Starting in the 20th century, with the appearance of anesthesia, there was a great advance in medicine with aless suffering of animals. In this century also, the first laws for the protection of companion animals, livestock and experimentation appeared:
- 1966. Animal Welfare Act, in the United States of America.
- 1976. Cruelty to Animals Act, in England.
- 1978. Good laboratory Practice (issued by the “Food and Drug Administration” FDA), in the United States of America.
- 1978. Ethical Principles and Guidelines for Scientific Experiments on Animals, in Switzerland.
Due to the growing general malaise of the population, which is increasingly against the use of animals in any field, it has been necessary to create laws in favor of protection of animals, whatever its use. The following laws, decrees and conventions have been enacted in Europe:
- European Convention on the Protection of Vertebrate Animals Used for Experimental and Other Scientific Purposes (Strasbourg, March 18, 1986).
- November 24, 1986, the Council of Europe has published a Directive on the approximation of the laws, regulations and administrative provisions of the Member States regarding the protection of animals used for experimentation and other scientific purposes.
- DIRECTIVE 2010/63/EU OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of September 22, 2010 on the protection of animals used for scientific purposes.
Initially, Spain limited itself to transferring Europe's demands to the Spanish legislation (ROYAL DECREE 223/1988 of 14 March, on the protection of animals used for experimentation and other scientific purposes.). But later new laws were added, such as Law 32/2007, of November 7, for the care of animals, in their exploitation, transport, experimentation and sacrifice, incorporates a sanctioning system.
Alternatives to animal testing
The use of alternative techniques to experimentation with animals is not, in the first place, to put an end to them. Alternatives to animal testing emerged in 1959 when Russell and Burch proposed the 3 R's: replacement, reduction, and refinement.
The replacement alternatives are those techniques that substitute the use of live animals. Russel and Burch differentiated between relative replacement, in which the vertebrate animal is euthanized to work with its cells, organs, or tissues, and absolute replacement, in which vertebrates are replaced by cultures of human cells, invertebrates and other tissues.
Regarding reduction, there is evidence that poor experimental design and flawed statistical analysis lead to misuse of animals, their lives being biased without any use. the least number of animals possible should be used, so an ethics committee must assess whether the design of the experiment and the statistics to be used are correct. In addition, phylogenetically inferior animals or embryos can be used.
The refinement of the techniques makes the potential pain that an animal may suffer is minimal or non-existent. Animal welfare must be kept above all else. There should be no physiological, psychological or environmental stress. To do this, use anesthetics and tranquilizers during possible interventions and environmental enrichment in the animal's housing, so that it can carry out its natural ethology.
Animal testing pros and cons
The main drawback of the use of experimental animals is the use of the animals itself, the potential harm that is inflicted on them and the physical and mental pain they may suffer. Discarding the total use of experimental animals is not currently possible, so advances should be aimed at reducing their use and combining them with alternative techniques such as computer programs and the use of tissues, as well as urging politicians tostrengthen the legislation that regulates the use of these animals, in addition to continuing to create committees to ensure proper handling of these animals and prohibit painful techniques or the repetition of experiments already carried out.
The animals used in experimentation are used for their similarity to humans, the diseases we suffer are very similar to theirs, so everything studied for us has been applied to veterinary medicine. All the medical and veterinary advances would not have been possible (unfortunately) without these animals. Therefore, it is necessary to continue investing in those scientific groups that advocate the end, in the future, of the use of experimental animals and, in the meantime, continue fighting because animals "in buckets" no suffer at all
