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Argumentative Essays on Animal Testing

Hook examples for animal testing essays, the ethical dilemma hook.

Begin your essay by presenting the ethical dilemma surrounding animal testing. Explore the moral questions it raises and the conflicting viewpoints of proponents and opponents.

The Historical Perspective Hook

Take your readers on a journey through the history of animal testing. Discuss its origins, evolution, and its role in scientific and medical advancements over time.

The Scientific Advancements Hook

Highlight the scientific breakthroughs and discoveries that have resulted from animal testing. Discuss how it has contributed to medical treatments, vaccines, and the understanding of diseases.

The Alternatives and Innovations Hook

Explore alternative methods and innovations in research that aim to replace or reduce the use of animals in testing. Discuss advancements like in vitro testing and computer modeling.

The Animal Welfare Hook

Focus on the welfare and ethical treatment of animals used in testing. Discuss regulations, guidelines, and efforts to minimize harm and suffering in research.

The Legal and Regulatory Landscape Hook

Examine the legal and regulatory framework surrounding animal testing in different countries. Discuss laws, restrictions, and their enforcement.

The Public Opinion and Activism Hook

Discuss public perceptions of animal testing and the role of animal rights activists in advocating for change. Highlight notable campaigns and their impact.

The Unintended Consequences Hook

Explore unintended consequences or risks associated with animal testing, such as potential harm to humans due to species differences or the limitations of animal models.

The Future of Research Hook

Discuss the future of scientific research and the possibilities for reducing or eliminating animal testing. Explore emerging technologies and trends in biomedical research.

The Personal Story Hook

Share a personal or anecdotal story related to animal testing, such as the experiences of a researcher, activist, or someone affected by medical advancements achieved through animal testing.

The Negative Consequences of Animal Testing

Ethical statement for animal testing, made-to-order essay as fast as you need it.

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Persuasive Essay Against Animal Testing

Arguments aganist using animals in experiments and testing, reasons to stop animal testing, the reasons why animal testing should be stopped, let us write you an essay from scratch.

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Discussion Whether Animals Testing is Necessary

An argument favoring the use of animals in testing and the benefits it has brought, animal testing in modern world, pros and cons of animal testing: the conflicting debate, get a personalized essay in under 3 hours.

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The Ethics of Animal Testing: an Argument Against Its Practice

Discussion: should animals be used for scientific research, the arguments concerning animal testing, why animal testing should be viewed as beneficial, saving the animals: alternative ways to test products, discussion on whether scientists should be allowed to test products on animals, the arguments why we should not test on animals, reasons why animal testing should be forbidden, why we should not continue test on animals, arguments for the reduction of animal testing, the problem of human cruelty to animals, how animal testing benefits us from diseases, stop the cruel and unnecessary animal testing, animal testing and alternatives for developing cruelty-free makeup, animals should not be a part of scientific research, worldwide problem of animal testing, analysis of the perspectives in support for animal testing and against it, animal testing in the united states, animal testing in the world, arguments for eliminating the use of animal testing.

Animal testing, referred to as animal experimentation, animal research, or in vivo testing, involves the utilization of animals other than humans in scientific experiments aimed at manipulating the factors influencing the behavior or biological processes being investigated.

Throughout history, the practice of animal testing has deep roots dating back centuries. The earliest recorded instances can be traced back to ancient civilizations, where animals were used for various scientific and medical purposes. The Greek physician Galen, during the second century AD, conducted experiments on animals to understand human anatomy and physiology. However, the formal establishment of animal testing as a systematic approach began to take shape during the 19th century with the emergence of modern medical research. In the late 1800s, advances in scientific knowledge and technology led to an increased demand for animal testing in various fields, including medicine, toxicology, and physiology. The development of anesthesia further facilitated the experimentation on animals by reducing pain and discomfort. Throughout the 20th century, animal testing became more widespread and institutionalized, particularly in the pharmaceutical industry.

Public opinion on animal testing is a complex and diverse topic, with viewpoints spanning a wide spectrum. While there are those who support the use of animals in scientific research for the advancement of human knowledge and medical breakthroughs, others express strong opposition due to ethical concerns and the perceived mistreatment of animals. Some people argue that animal testing is necessary for the development of life-saving treatments and the improvement of human health. They believe that animals provide valuable insights into human biology and the effectiveness of potential therapies. On the other hand, opponents of animal testing argue that it is cruel and unnecessary, advocating for alternative methods such as in vitro testing, computer modeling, and human cell-based assays. Public opinion on animal testing often hinges on the balance between scientific progress and animal welfare. The growing awareness of animal rights and ethical considerations has fueled debates and discussions surrounding the topic. As society becomes more conscious of animal welfare, there is an increasing demand for alternative testing methods and greater transparency in the treatment of animals involved in research. Ultimately, public opinion plays a crucial role in shaping policies and regulations surrounding animal testing.

1. Scientific advancement. 2. Human health and safety. 3. Understanding diseases. 4. Regulatory requirements. 5. Animal welfare improvements.

1. Ethical concerns. 2. Inadequate human relevance. 3. Availability of alternatives. 4. Animal welfare. 5. Speciesism and moral status.

One example of media representation is the documentary "Earthlings" directed by Shaun Monson. This influential film explores different aspects of animal exploitation, including animal testing, and highlights the ethical concerns surrounding the practice. It has garnered widespread attention and prompted discussions about the treatment of animals in scientific research. Social media platforms have also become powerful tools for activists and organizations to share information and advocate for alternatives to animal testing. Hashtags like #StopAnimalTesting and #CrueltyFree have gained traction, raising awareness and encouraging conversations on the topic.

The topic of animal testing is important due to its ethical, scientific, and societal implications. From an ethical standpoint, it raises profound questions about the treatment of sentient beings and the moral responsibility we have towards animals. It prompts us to consider the balance between scientific progress and animal welfare, urging us to explore alternative methods that minimize harm. Scientifically, animal testing has been instrumental in advancing medical knowledge and developing treatments for various diseases. However, it is essential to continually evaluate its effectiveness, limitations, and potential alternatives to ensure both human and animal well-being. Furthermore, the issue of animal testing has societal implications as it reflects our values and priorities as a society. It prompts discussions about our relationship with animals, the extent of their rights, and the importance of promoting more humane practices.

The topic of animal testing is worth writing an essay about due to its complex nature and the multitude of perspectives it encompasses. It is a subject that elicits strong emotions and raises critical ethical, scientific, and social questions. Writing an essay on animal testing allows for an in-depth exploration of these issues and encourages critical thinking and analysis. By delving into the topic, one can examine the ethical considerations surrounding the use of animals in experiments, weighing the potential benefits against the moral implications. Additionally, it provides an opportunity to evaluate the scientific validity and reliability of animal testing as a method for understanding human biology and developing medical treatments. Furthermore, an essay on animal testing opens avenues for discussing alternative approaches and advancements in technology that can reduce or replace animal experimentation. It allows for an exploration of the societal impact of animal testing, including public opinion, legislation, and the influence of media.

1. Each year, millions of animals are used in scientific experiments worldwide. According to estimates, over 100 million animals, including rabbits, mice, rats, dogs, and primates, are subjected to testing for various purposes, such as biomedical research, drug development, and toxicity testing. 2. Animal testing is not always reliable in predicting human outcomes. Studies have shown that there can be significant differences between animals and humans in terms of anatomy, physiology, and drug metabolism. This raises concerns about the validity and relevance of using animal models for understanding human diseases and developing treatments. 3. Alternatives to animal testing are emerging and gaining traction. Scientists and researchers are actively exploring innovative methods, such as in vitro cell cultures, computer modeling, and organ-on-a-chip technology, to simulate human biology and predict human responses more accurately. These alternative approaches aim to reduce or eliminate the need for animal testing while still ensuring the safety and efficacy of new products and treatments.

1. Abbott, A. (2005). Animal testing: more than a cosmetic change. Nature, 438(7065), 144-147. (https://go.gale.com/ps/i.do?id=GALE%7CA185466349&sid=googleScholar&v=2.1&it=r&linkaccess=abs&issn=00280836&p=AONE&sw=w&userGroupName=anon%7E513ffe31) 2. Doke, S. K., & Dhawale, S. C. (2015). Alternatives to animal testing: A review. https://www.sciencedirect.com/science/article/pii/S1319016413001096 Saudi Pharmaceutical Journal, 23(3), 223-229. 3. Hajar, R. (2011). Animal testing and medicine. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3123518/ Heart views: the official journal of the Gulf Heart Association, 12(1), 42. 4. Bottini, A. A., & Hartung, T. (2009). Food for thought… on the economics of animal testing. ALTEX-Alternatives to animal experimentation, 26(1), 3-16. (https://www.altex.org/index.php/altex/article/view/633) 5. Valappil, S. P., Misra, S. K., Boccaccini, A. R., & Roy, I. (2006). Biomedical applications of polyhydroxyalkanoates, an overview of animal testing and in vivo responses. Expert Review of Medical Devices, 3(6), 853-868. (https://www.tandfonline.com/doi/abs/10.1586/17434440.3.6.853) 6. File, S. E., Lippa, A. S., Beer, B., & Lippa, M. T. (2004). Animal tests of anxiety. Current protocols in neuroscience, 26(1), 8-3. (https://currentprotocols.onlinelibrary.wiley.com/doi/abs/10.1002/0471142301.ns0803s26) 7. Madden, J. C., Enoch, S. J., Paini, A., & Cronin, M. T. (2020). A review of in silico tools as alternatives to animal testing: principles, resources and applications. Alternatives to Laboratory Animals, 48(4), 146-172. (https://journals.sagepub.com/doi/pdf/10.1177/0261192920965977) 8. Donnellan, L. (2006). Animal testing in cosmetics: recent developments in the European Union and the United States. Animal L., 13, 251. (https://heinonline.org/HOL/LandingPage?handle=hein.journals/anim13&div=18&id=&page=)

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• Published: 01 February 2002

Animal experimentation: the continuing debate

• Mark Matfield 1  

Nature Reviews Drug Discovery volume  1 ,  pages 149–152 ( 2002 ) Cite this article

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The use of animals in research and development has remained a subject of public debate for over a century. Although there is good evidence from opinion surveys that the public accepts the use of animals in research, they are poorly informed about the way in which it is regulated, and are increasingly concerned about laboratory-animal welfare. This article will review how public concerns about animal experimentation developed, the recent activities of animal-rights groups, and the opportunities and challenges facing the scientific community.

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Ethical care for research animals

WHY ANIMAL RESEARCH?

The use of animals in some forms of biomedical research remains essential to the discovery of the causes, diagnoses, and treatment of disease and suffering in humans and in animals., stanford shares the public's concern for laboratory research animals..

Many people have questions about animal testing ethics and the animal testing debate. We take our responsibility for the ethical treatment of animals in medical research very seriously. At Stanford, we emphasize that the humane care of laboratory animals is essential, both ethically and scientifically.  Poor animal care is not good science. If animals are not well-treated, the science and knowledge they produce is not trustworthy and cannot be replicated, an important hallmark of the scientific method .

There are several reasons why the use of animals is critical for biomedical research: 

••  Animals are biologically very similar to humans. In fact, mice share more than 98% DNA with us!

••  Animals are susceptible to many of the same health problems as humans – cancer, diabetes, heart disease, etc.

••  With a shorter life cycle than humans, animal models can be studied throughout their whole life span and across several generations, a critical element in understanding how a disease processes and how it interacts with a whole, living biological system.

The ethics of animal experimentation

Nothing so far has been discovered that can be a substitute for the complex functions of a living, breathing, whole-organ system with pulmonary and circulatory structures like those in humans. Until such a discovery, animals must continue to play a critical role in helping researchers test potential new drugs and medical treatments for effectiveness and safety, and in identifying any undesired or dangerous side effects, such as infertility, birth defects, liver damage, toxicity, or cancer-causing potential.

U.S. federal laws require that non-human animal research occur to show the safety and efficacy of new treatments before any human research will be allowed to be conducted.  Not only do we humans benefit from this research and testing, but hundreds of drugs and treatments developed for human use are now routinely used in veterinary clinics as well, helping animals live longer, healthier lives.

It is important to stress that 95% of all animals necessary for biomedical research in the United States are rodents – rats and mice especially bred for laboratory use – and that animals are only one part of the larger process of biomedical research.

Our researchers are strong supporters of animal welfare and view their work with animals in biomedical research as a privilege.

Stanford researchers are obligated to ensure the well-being of all animals in their care..

Stanford researchers are obligated to ensure the well-being of animals in their care, in strict adherence to the highest standards, and in accordance with federal and state laws, regulatory guidelines, and humane principles. They are also obligated to continuously update their animal-care practices based on the newest information and findings in the fields of laboratory animal care and husbandry.  

Researchers requesting use of animal models at Stanford must have their research proposals reviewed by a federally mandated committee that includes two independent community members.  It is only with this committee’s approval that research can begin. We at Stanford are dedicated to refining, reducing, and replacing animals in research whenever possible, and to using alternative methods (cell and tissue cultures, computer simulations, etc.) instead of or before animal studies are ever conducted.

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There are many outreach and advocacy organizations in the field of biomedical research.

• Learn more about outreach and advocacy organizations

Stanford Discoveries

What are the benefits of using animals in research? Stanford researchers have made many important human and animal life-saving discoveries through their work. 

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• v.63(2 Suppl 3); 2022 Jun

Ethical considerations regarding animal experimentation

Aysha karim kiani.

1 Allama Iqbal Open University, Islamabad, Pakistan

2 MAGI EUREGIO, Bolzano, Italy

DEREK PHEBY

3 Society and Health, Buckinghamshire New University, High Wycombe, UK

GARY HENEHAN

4 School of Food Science and Environmental Health, Technological University of Dublin, Dublin, Ireland

RICHARD BROWN

5 Department of Psychology and Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada

PAUL SIEVING

6 Department of Ophthalmology, Center for Ocular Regenerative Therapy, School of Medicine, University of California at Davis, Sacramento, CA, USA

PETER SYKORA

7 Department of Philosophy and Applied Philosophy, University of St. Cyril and Methodius, Trnava, Slovakia

ROBERT MARKS

8 Department of Biotechnology Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel

BENEDETTO FALSINI

9 Institute of Ophthalmology, Università Cattolica del Sacro Cuore, Fondazione Policlinico Universitario A. Gemelli-IRCCS, Rome, Italy

NATALE CAPODICASA

10 MAGI BALKANS, Tirana, Albania

STANISLAV MIERTUS

11 Department of Biotechnology, University of SS. Cyril and Methodius, Trnava, Slovakia

12 International Centre for Applied Research and Sustainable Technology, Bratislava, Slovakia

LORENZO LORUSSO

13 UOC Neurology and Stroke Unit, ASST Lecco, Merate, Italy

DANIELE DONDOSSOLA

14 Center for Preclincal Research and General and Liver Transplant Surgery Unit, Fondazione IRCCS Ca‘ Granda Ospedale Maggiore Policlinico, Milan, Italy

15 Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy

GIANLUCA MARTINO TARTAGLIA

16 Department of Biomedical, Surgical and Dental Sciences, Università degli Studi di Milano, Milan, Italy

17 UOC Maxillo-Facial Surgery and Dentistry, Fondazione IRCCS Ca Granda, Ospedale Maggiore Policlinico, Milan, Italy

MAHMUT CERKEZ ERGOREN

18 Department of Medical Genetics, Faculty of Medicine, Near East University, Nicosia, Cyprus

MUNIS DUNDAR

19 Department of Medical Genetics, Erciyes University Medical Faculty, Kayseri, Turkey

SANDRO MICHELINI

20 Vascular Diagnostics and Rehabilitation Service, Marino Hospital, ASL Roma 6, Marino, Italy

DANIELE MALACARNE

21 MAGI’S LAB, Rovereto (TN), Italy

GABRIELE BONETTI

Astrit dautaj, kevin donato, maria chiara medori, tommaso beccari.

22 Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy

MICHELE SAMAJA

23 MAGI GROUP, San Felice del Benaco (BS), Italy

STEPHEN THADDEUS CONNELLY

24 San Francisco Veterans Affairs Health Care System, University of California, San Francisco, CA, USA

DONALD MARTIN

25 Univ. Grenoble Alpes, CNRS, Grenoble INP, TIMC-IMAG, SyNaBi, Grenoble, France

ASSUNTA MORRESI

26 Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy

ARIOLA BACU

27 Department of Biotechnology, University of Tirana, Tirana, Albania

KAREN L. HERBST

28 Total Lipedema Care, Beverly Hills California and Tucson Arizona, USA

MYKHAYLO KAPUSTIN

29 Federation of the Jewish Communities of Slovakia

LIBORIO STUPPIA

30 Department of Psychological, Health and Territorial Sciences, School of Medicine and Health Sciences, University "G. d'Annunzio", Chieti, Italy

LUDOVICA LUMER

31 Department of Anatomy and Developmental Biology, University College London, London, UK

GIAMPIETRO FARRONATO

Matteo bertelli.

32 MAGISNAT, Peachtree Corners (GA), USA

Animal experimentation is widely used around the world for the identification of the root causes of various diseases in humans and animals and for exploring treatment options. Among the several animal species, rats, mice and purpose-bred birds comprise almost 90% of the animals that are used for research purpose. However, growing awareness of the sentience of animals and their experience of pain and suffering has led to strong opposition to animal research among many scientists and the general public. In addition, the usefulness of extrapolating animal data to humans has been questioned. This has led to Ethical Committees’ adoption of the ‘four Rs’ principles (Reduction, Refinement, Replacement and Responsibility) as a guide when making decisions regarding animal experimentation. Some of the essential considerations for humane animal experimentation are presented in this review along with the requirement for investigator training. Due to the ethical issues surrounding the use of animals in experimentation, their use is declining in those research areas where alternative in vitro or in silico methods are available. However, so far it has not been possible to dispense with experimental animals completely and further research is needed to provide a road map to robust alternatives before their use can be fully discontinued.

How to cite this article: Kiani AK, Pheby D, Henehan G, Brown R, Sieving P, Sykora P, Marks R, Falsini B, Capodicasa N, Miertus S, Lorusso L, Dondossola D, Tartaglia GM, Ergoren MC, Dundar M, Michelini S, Malacarne D, Bonetti G, Dautaj A, Donato K, Medori MC, Beccari T, Samaja M, Connelly ST, Martin D, Morresi A, Bacu A, Herbst KL, Kapustin M, Stuppia L, Lumer L, Farronato G, Bertelli M. Ethical considerations regarding animal experimentation. J Prev Med Hyg 2022;63(suppl.3):E255-E266. https://doi.org/10.15167/2421-4248/jpmh2022.63.2S3.2768

Introduction

Animal model-based research has been performed for a very long time. Ever since the 5 th century B.C., reports of experiments involving animals have been documented, but an increase in the frequency of their utilization has been observed since the 19 th century [ 1 ]. Most institutions for medical research around the world use non-human animals as experimental subjects [ 2 ]. Such animals might be used for research experimentations to gain a better understanding of human diseases or for exploring potential treatment options [ 2 ]. Even those animals that are evolutionarily quite distant from humans, such as Drosophila melanogaster , Zebrafish ( Danio rerio ) and Caenorhabditis elegans , share physiological and genetic similarities with human beings [ 2 ]; therefore animal experimentation can be of great help for the advancement of medical science [ 2 ].

For animal experimentation, the major assumption is that the animal research will be of benefit to humans. There are many reasons that highlight the significance of animal use in biomedical research. One of the major reasons is that animals and humans share the same biological processes. In addition, vertebrates have many anatomical similarities (all vertebrates have lungs, a heart, kidneys, liver and other organs) [ 3 ]. Therefore, these similarities make certain animals more suitable for experiments and for providing basic training to young researchers and students in different fields of biological and biomedical sciences [ 3 ]. Certain animals are susceptible to various health problems that are similar to human diseases such as diabetes, cancer and heart disease [ 4 ]. Furthermore, there are genetically modified animals that are used to obtain pathological phenotypes [ 5 ]. A significant benefit of animal experimentation is that test species can be chosen that have a much shorter life cycle than humans. Therefore, animal models can be studied throughout their life span and for several successive generations, an essential element for the understanding of disease progression along with its interaction with the whole organism throughout its lifetime [ 6 ].

Animal models often play a critical role in helping researchers who are exploring the efficacy and safety of potential medical treatments and drugs. They help to identify any dangerous or undesired side effects, such as birth defects, infertility, toxicity, liver damage or any potential carcinogenic effects [ 7 ]. Currently, U.S. Federal law, for example, requires that non-human animal research is used to demonstrate the efficacy and safety of any new treatment options before proceeding to trials on humans [ 8 ]. Of course, it is not only humans benefit from this research and testing, since many of the drugs and treatments that are developed for humans are routinely used in veterinary clinics, which help animals live longer and healthier lives [ 4 ].

COVID-19 AND THE NEED FOR ANIMAL MODELS

When COVID-19 struck, there was a desperate need for research on the disease, its effects on the brain and body and on the development of new treatments for patients with the disease. Early in the disease it was noticed that those with the disease suffered a loss of smell and taste, as well as neurological and psychiatric symptoms, some of which lasted long after the patients had “survived” the disease [ 9-15 ]. As soon as the pandemic started, there was a search for appropriate animal models in which to study this unknown disease [ 16 , 17 ]. While genetically modified mice and rats are the basic animal models for neurological and immunological research [ 18 , 19 ] the need to understand COVID-19 led to a range of animal models; from fruit flies [ 20 ] and Zebrafish [ 21 ] to large mammals [ 22 , 23 ] and primates [ 24 , 25 ]. And it was just not one animal model that was needed, but many, because different aspects of the disease are best studied in different animal models [ 16 , 25 , 26 ]. There is also a need to study the transmission pathways of the zoonosis: where does it come from, what are the animal hosts and how is it transferred to humans [ 27 ]?

There has been a need for animal models for understanding the pathophysiology of COVID-19 [ 28 ], for studying the mechanisms of transmission of the disease [ 16 ], for studying its neurobiology [ 29 , 30 ] and for developing new vaccines [ 31 ]. The sudden onset of the COVID-19 pandemic has highlighted the fact that animal research is necessary, and that the curtailment of such research has serious consequences for the health of both humans and animals, both wild and domestic [ 32 ] As highlighted by Adhikary et al. [ 22 ] and Genzel et al. [ 33 ] the coronavirus has made clear the necessity for animal research and the danger in surviving future such pandemics if animal research is not fully supported. Genzel et al. [ 33 ], in particular, take issue with the proposal for a European ban on animal testing. Finally, there is a danger in bypassing animal research in developing new vaccines for diseases such as COVID-19 [ 34 ]. The purpose of this paper is to show that, while animal research is necessary for the health of both humans and animals, there is a need to carry out such experimentation in a controlled and humane manner. The use of alternatives to animal research such as cultured human cells and computer modeling may be a useful adjunct to animal studies but will require that such methods are more readily accessible to researchers and are not a replacement for animal experimentation.

Pros and cons of animal experimentation

Arguments against animal experimentation.

A fundamental question surrounding this debate is to ask whether it is appropriate to use animals for medical research. Is our acceptance that animals have a morally lower value or standard of life just a case of speciesism [ 35 ]? Nowadays, most people agree that animals have a moral status and that needlessly hurting or abusing pets or other animals is unacceptable. This represents something of a change from the historical point of view where animals did not have any moral status and the treatment of animals was mostly subservient to maintaining the health and dignity of humans [ 36 ].

Animal rights advocates strongly argue that the moral status of non-human animals is similar to that of humans, and that animals are entitled to equality of treatment. In this view, animals should be treated with the same level of respect as humans, and no one should have the right to force them into any service or to kill them or use them for their own goals. One aspect of this argument claims that moral status depends upon the capacity to suffer or enjoy life [ 37 ].

In terms of suffering and the capacity of enjoying life, many animals are not very different from human beings, as they can feel pain and experience pleasure [ 38 ]. Hence, they should be given the same moral status as humans and deserve equivalent treatment. Supporters of this argument point out that according animals a lower moral status than humans is a type of prejudice known as “speciesism” [ 38 ]. Among humans, it is widely accepted that being a part of a specific race or of a specific gender does not provide the right to ascribe a lower moral status to the outsiders. Many advocates of animal rights deploy the same argument, that being human does not give us sufficient grounds declare animals as being morally less significant [ 36 ].

ARGUMENTS IN FAVOR OF ANIMAL EXPERIMENTATION

Those who support animal experimentation have frequently made the argument that animals cannot be elevated to be seen as morally equal to humans [ 39 ]. Their main argument is that the use of the terms “moral status” or “morality” is debatable. They emphasize that we must not make the error of defining a quality or capacity associated with an animal by using the same adjectives used for humans [ 39 ]. Since, for the most part, animals do not possess humans’ cognitive capabilities and lack full autonomy (animals do not appear to rationally pursue specific goals in life), it is argued that therefore, they cannot be included in the moral community [ 39 ]. It follows from this line of argument that, if animals do not possess the same rights as human beings, their use in research experimentation can be considered appropriate [ 40 ]. The European and the American legislation support this kind of approach as much as their welfare is respected.

Another aspect of this argument is that the benefits to human beings of animal experimentation compensate for the harm caused to animals by these experiments.

In other words, animal harm is morally insignificant compared to the potential benefits to humans. Essentially, supporters of animal experimentation claim that human beings have a higher moral status than animals and that animals lack certain fundamental rights accorded to humans. The potential violations of animal rights during animal research are, in this way, justified by the greater benefits to mankind [ 40 , 41 ]. A way to evaluate when the experiments are morally justified was published in 1986 by Bateson, which developed the Bateson’s Cube [ 42 ]. The Cube has three axes: suffering, certainty of benefit and quality of research. If the research is high-quality, beneficial, and not inflicting suffering, it will be acceptable. At the contrary, painful, low-quality research with lower likelihood of success will not be acceptable [ 42 , 43 ].

Impact of experimentations on animals

Ability to feel pain and distress.

Like humans, animal have certain physical as well as psychological characteristics that make their use for experimentation controversial [ 44 ].

In the last few decades, many studies have increased knowledge of animal awareness and sentience: they indicate that animals have greater potential to experience damage than previously appreciated and that current rights and protections need to be reconsidered [ 45 ]. In recent times, scientists as well as ethicists have broadly acknowledged that animals can also experience distress and pain [ 46 ]. Potential sources of such harm arising from their use in research include disease, basic physiological needs deprivation and invasive procedures [ 46 ]. Moreover, social deprivation and lack of the ability to carry out their natural behaviors are other causes of animal harm [ 46 ]. Several studies have shown that, even in response to very gentle handling and management, animals can show marked alterations in their physiological and hormonal stress markers [ 47 ].

In spite of the fact that suffering and pain are personalized experiences, several multi-disciplinary studies have provided clear evidence of animals experiencing pain and distress. In particular, some animal species have the ability to express pain similarly to human due to common psychological, neuroanatomical and genetic characteristics [ 48 ]. Similarly, animals share a resemblance to humans in their developmental, genetic and environmental risk factors for psychopathology. For instance, in many species, it has been shown that fear operates within a less organized subcortical neural circuit than pain [ 49 , 50 ]. Various types of depression and anxiety disorders like posttraumatic stress disorder have also been reported in mammals [ 51 ].

PSYCHOLOGICAL CAPABILITIES OF ANIMALS

Some researchers have suggested that besides their ability to experience physical and psychological pain and distress, some animals also exhibit empathy, self-awareness and language-like capabilities. They also demonstrate tools-linked cognizance, pleasure-seeking and advanced problem-solving skills [ 52 ]. Moreover, mammals and birds exhibit playful behavior, an indicator of the capacity to experience pleasure. Other taxa such as reptiles, cephalopods and fishes have also been observed to display playful behavior, therefore the current legislation prescribes the use of environmental enrichers [ 53 ]. The presence of self-awareness ability, as assessed by mirror self-recognition, has been reported in magpies, chimpanzees and other apes, and certain cetaceans [ 54 ]. Recently, another study has revealed that crows have the ability to create and use tools that involve episodic-like memory formation and its retrieval. From these findings, it may be suggested that crows as well as related species show evidence of flexible learning strategies, causal reasoning, prospection and imagination that are similar to behavior observed in great apes [ 55 ]. In the context of resolving the ethical dilemmas about animal experimentation, these observations serve to highlight the challenges involved [ 56 , 57 ].

Ethics, principles and legislation in animal experimentation

Ethics in animal experimentation.

Legislation around animal research is based on the idea of the moral acceptability of the proposed experiments under specific conditions [ 58 ]. The significance of research ethics that ensures proper treatment of experimental animals [ 58 ]. To avoid undue suffering of animals, it is important to follow ethical considerations during animal studies [ 1 ]. It is important to provide best human care to these animals from the ethical and scientific point of view [ 1 ]. Poor animal care can lead to experimental outcomes [ 1 ]. Thus, if experimental animals mistreated, the scientific knowledge and conclusions obtained from experiments may be compromised and may be difficult to replicate, a hallmark of scientific research [ 1 ]. At present, most ethical guidelines work on the assumption that animal experimentation is justified because of the significant potential benefits to human beings. These guidelines are often permissive of animal experimentation regardless of the damage to the animal as long as human benefits are achieved [ 59 ].

PRINCIPLE OF THE 4 RS

Although animal experimentation has resulted in many discoveries and helped in the understanding numerous aspects of biological science, its use in various sectors is strictly controlled. In practice, the proposed set of animal experiments is usually considered by a multidisciplinary Ethics Committee before work can commence [ 60 ]. This committee will review the research protocol and make a judgment as to its sustainability. National and international laws govern the utilization of animal experimentation during research and these laws are mostly based on the universal doctrine presented by Russell and Burch (1959) known as principle of the 3 Rs. The 3Rs referred to are Reduction, Refinement and Replacement, and are applied to protocols surrounding the use of animals in research. Some researchers have proposed another “R”, of responsibility for the experimental animal as well as for the social and scientific status of the animal experiments [ 61 ]. Thus, animal ethics committees commonly review research projects with reference to the 4 Rs principles [ 62 ].

The first “R”, Reduction means that the experimental design is examined to ensure that researchers have reduced the number of experimental animals in a research project to the minimum required for reliable data [ 59 ]. Methods used for this purpose include improved experimental design, extensive literature search to avoid duplication of experiments [ 35 ], use of advanced imaging techniques, sharing resources and data, and appropriate statistical data analysis that reduce the number of animals needed for statistically significant results [ 2 , 63 ].

The second “R”, Refinement involves improvements in procedure that minimize the harmful effects of the proposed experiments on the animals involved, such as reducing pain, distress and suffering in a manner that leads to a general improvement in animal welfare. This might include for example improved living conditions for research animals, proper training of people handling animals, application of anesthesia and analgesia when required and the need for euthanasia of the animals at the end of the experiment to curtail their suffering [ 63 ].

The third “R”, Replacement refers to approaches that replace or avoid the use of experimental animals altogether. These approaches involve use of in silico methods/computerized techniques/software and in vitro methods like cell and tissue culture testing, as well as relative replacement methods by use of invertebrates like nematode worms, fruit flies and microorganisms in place of vertebrates and higher animals [ 1 ]. Examples of proper application of these first “3R2 principles are the use of alternative sources of blood, the exploitation of commercially used animals for scientific research, a proper training without use of animals and the use of specimen from previous experiments for further researches [ 64-67 ].

The fourth “R”, Responsibility refers to concerns around promoting animal welfare by improvements in experimental animals’ social life, development of advanced scientific methods for objectively determining sentience, consciousness, experience of pain and intelligence in the animal kingdom, as well as effective involvement in the professionalization of the public discussion on animal ethics [ 68 ].

OTHER ASPECTS OF ANIMAL RESEARCH ETHICS

Other research ethics considerations include having a clear rationale and reasoning for the use of animals in a research project. Researchers must have reasonable expectation of generating useful data from the proposed experiment. Moreover, the research study should be designed in such a way that it should involve the lowest possible sample size of experimental animals while producing statistically significant results [ 35 ].

All individual researchers that handle experimental animals should be properly trained for handling the particular species involved in the research study. The animal’s pain, suffering and discomfort should be minimized [ 69 ]. Animals should be given proper anesthesia when required and surgical procedures should not be repeated on same animal whenever possible [ 69 ]. The procedure of humane handling and care of experimental animals should be explicitly detailed in the research study protocol. Moreover, whenever required, aseptic techniques should be properly followed [ 70 ]. During the research, anesthetization and surgical procedures on experimental animals should only be performed by professionally skilled individuals [ 69 ].

The Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines that are issued by the National Center for the Replacement, Refinement, and Reduction of Animals in Research (NC3Rs) are designed to improve the documentation surrounding research involving experimental animals [ 70 ]. The checklist provided includes the information required in the various sections of the manuscript i.e. study design, ethical statements, experimental procedures, experimental animals and their housing and husbandry, and more [ 70 ].

It is critical to follow the highest ethical standards while performing animal experiments. Indeed, most of the journals refuse to publish any research data that lack proper ethical considerations [ 35 ].

INVESTIGATORS’ ETHICS

Since animals have sensitivity level similar to the human beings in terms of pain, anguish, survival instinct and memory, it is the responsibility of the investigator to closely monitor the animals that are used and identify any sign of distress [ 71 ]. No justification can rationalize the absence of anesthesia or analgesia in animals that undergo invasive surgery during the research [ 72 ]. Investigators are also responsible for giving high-quality care to the experimental animals, including the supply of a nutritious diet, easy water access, prevention of and relief from any pain, disease and injury, and appropriate housing facilities for the animal species [ 73 ]. A research experiment is not permitted if the damage caused to the animal exceeds the value of knowledge gained by that experiment. No scientific advancement based on the destruction and sufferings of another living being could be justified. Besides ensuring the welfare of animals involved, investigators must also follow the applicable legislation [ 74 , 75 ].

To promote the comfort of experimental animals in England, an animal protection society named: ‘The Society for the Preservation of Cruelty to Animals’ (now the Royal Society for the Prevention of Cruelty to Animals) was established (1824) that aims to prevent cruelty to animal [ 76 ].

ANIMAL WELFARE LAWS

Legislation for animal protection during research has long been established. In 1876 the British Parliament sanctioned the ‘Cruelty to Animals Act’ for animal protection. Russell and Burch (1959) presented the ‘3 Rs’ principles: Replacement, Reduction and Refinement, for use of animals during research [ 61 ]. Almost seven years later, the U.S.A also adopted regulations for the protection of experimental animals by enacting the Laboratory Animal Welfare Act of 1966 [ 60 ]. In Brazil, the Arouca Law (Law No. 11,794/08) regulates the animal use in scientific research experiments [ 76 ].

These laws define the breeding conditions, and regulate the use of animals for scientific research and teaching purposes. Such legal provisions control the use of anesthesia, analgesia or sedation in experiments that could cause distress or pain to experimental animals [ 59 , 76 ]. These laws also stress the need for euthanasia when an experiment is finished, or even during the experiment if there is any intense suffering for the experimental animal [ 76 ].

Several national and international organizations have been established to develop alternative techniques so that animal experimentation can be avoided, such as the UK-based National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) ( www.caat.jhsph.edu ), the European Centre for the Validation of Alternative Methods (ECVAM) [ 77 ], the Universities Federation for Animal Welfare (UFAW) ( www.ufaw.org.uk ), The Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) [ 78 ], and The Center for Alternatives to Animal Testing (CAAT) ( www.caat.jhsph.edu ). The Brazilian ‘Arouca Law’ also constitutes a milestone, as it has created the ‘National Council for the Control of Animal Experimentation’ (CONCEA) that deals with the legal and ethical issues related to the use of experimental animals during scientific research [ 76 ].

Although national as well as international laws and guidelines have provided basic protections for experimental animals, the current regulations have some significant discrepancies. In the U.S., the Animal Welfare Act excludes rats, mice and purpose-bred birds, even though these species comprise almost 90% of the animals that are used for research purpose [ 79 ]. On the other hand, certain cats and dogs are getting special attention along with extra protection. While the U.S. Animal Welfare Act ignores birds, mice and rats, the U.S. guidelines that control research performed using federal funding ensure protections for all vertebrates [ 79 , 80 ].

Living conditions of animals

Choice of the animal model.

Based on all the above laws and regulations and in line with the deliberations of ethical committees, every researcher must follow certain rules when dealing with animal models.

Before starting any experimental work, thorough research should be carried out during the study design phase so that the unnecessary use of experimental animals is avoided. Nevertheless, certain research studies may have compelling reasons for the use of animal models, such as the investigation of human diseases and toxicity tests. Moreover, animals are also widely used in the training of health professionals as well as in training doctors in surgical skills [ 1 , 81 ].

Researcher should be well aware of the specific traits of the animal species they intend to use in the experiment, such as its developmental stages, physiology, nutritional needs, reproductive characteristics and specific behaviors. Animal models should be selected on the basis of the study design and the biological relevance of the animal [ 1 ].

Typically, in early research, non-mammalian models are used to get rapid insights into research problems such as the identification of gene function or the recognition of novel therapeutic options. Thus, in biomedical and biological research, among the most commonly used model organisms are the Zebrafish, the fruit fly Drosophila melanogaster and the nematode Caenorhabditis elegans . The main advantage of these non-mammalian animal models is their prolific reproducibility along with their much shorter generation time. They can be easily grown in any laboratory setting, are less expensive than the murine animal models and are somewhat more powerful than the tissue and cell culture approaches [ 82 ].

Caenorhabditis elegans is a small-sized nematode with a short life cycle and that exists in large populations and is relatively inexpensive to cultivate. Scientists have gathered extensive knowledge of the genomics and genetics of Caenorhabditis elegans ; but Caenorhabditis elegans models, while very useful in some respects, are unable to represent all signaling pathways found in humans. Furthermore, due to its short life cycle, scientists are unable to investigate long term effects of test compounds or to analyze primary versus secondary effects [ 6 ].

Similarly, the fruit fly Drosophila melanogaster has played a key role in numerous biomedical discoveries. It is small in size, has a short life cycle and large population size, is relatively inexpensive to breed, and extensive genomics and genetics information is available [ 6 ]. However, its respiratory, cardiovascular and nervous systems differ considerably from human beings. In addition, its immune system is less developed when compared to vertebrates, which is why effectiveness of a drug in Drosophila melanogaster may not be easily extrapolated to humans [ 83 ].

The Zebrafish ( Danio rerio ) is a small freshwater teleost, with transparent embryos, providing easy access for the observation of organogenesis and its manipulation. Therefore, Zebrafish embryos are considered good animal models for different human diseases like tuberculosis and fetal alcohol syndrome and are useful as neurodevelopmental research models. However, Zebrafish has very few mutant strains available, and its genome has numerous duplicate genes making it impossible to create knockout strains, since disrupting one copy of the gene will not disrupt the second copy of that gene. This feature limits the use of Zebrafish as animal models to study human diseases. Additionally they are rather expensive, have long life cycle, and genomics and genetics studies are still in progress [ 82 , 84 ].

Thus, experimentation on these three animals might not be equivalent to experimentation on mammals. Mammalian animal model are most similar to human beings, so targeted gene replacement is possible. Traditionally, mammals like monkey and mice have been the preferred animal models for biomedical research because of their evolutionary closeness to humans. Rodents, particularly mice and rats, are the most frequently used animal models for scientific research. Rats are the most suitable animal model for the study of obesity, shock, peritonitis, sepsis, cancer, intestinal operations, spleen, gastric ulcers, mononuclear phagocytic system, organ transplantations and wound healing. Mice are more suitable for studying burns, megacolon, shock, cancer, obesity, and sepsis as mentioned previously [ 85 ].

Similarly, pigs are mostly used for stomach, liver and transplantation studies, while rabbits are suitable for the study of immunology, inflammation, vascular biology, shock, colitis and transplantations. Thus, the choice of experimental animal mainly depends upon the field of scientific research under consideration [ 1 ].

HOUSING AND ENVIRONMENTAL ENRICHMENT

Researchers should be aware of the environment and conditions in which laboratory animals are kept during research, and they also need to be familiar with the metabolism of the animals kept in vivarium, since their metabolism can easily be altered by different factors such as pain, stress, confinement, lack of sunlight, etc. Housing conditions alter animal behavior, and this can in turn affect experimental results. By contrast, handling procedures that feature environmental enrichment and enhancement help to decrease stress and positively affect the welfare of the animals and the reliability of research data [ 74 , 75 ].

In animals, distress- and agony-causing factors should be controlled or eliminated to overcome any interference with data collection as well as with interpretation of the results, since impaired animal welfare leads to more animal usage during experiment, decreased reliability and increased discrepancies in results along with the unnecessary consumption of animal lives [ 86 ].

To reduce the variation or discrepancies in experimental data caused by various environmental factors, experimental animals must be kept in an appropriate and safe place. In addition, it is necessary to keep all variables like humidity, airflow and temperature at levels suitable for those species, as any abrupt variation in these factors could cause stress, reduced resistance and increased susceptibility to infections [ 74 ].

The space allotted to experimental animals should permit them free movement, proper sleep and where feasible allow for interaction with other animals of the same species. Mice and rats are quite sociable animals and must, therefore, be housed in groups for the expression of their normal behavior. Usually, laboratory cages are not appropriate for the behavioral needs of the animals. Therefore, environmental enrichment is an important feature for the expression of their natural behavior that will subsequently affect their defense mechanisms and physiology [ 87 ].

The features of environmental enrichment must satisfy the animals’ sense of curiosity, offer them fun activities, and also permit them to fulfill their behavioral and physiological needs. These needs include exploring, hiding, building nests and gnawing. For this purpose, different things can be used in their environment, such as PVC tubes, cardboard, igloos, paper towel, cotton, disposable masks and paper strips [ 87 ].

The environment used for housing of animals must be continuously controlled by appropriate disinfection, hygiene protocols, sterilization and sanitation processes. These steps lead to a reduction in the occurrence of various infectious agents that often found in vivarium, such as Sendai virus, cestoda and Mycoplasma pulmonis [ 88 ].

Euthanasia is a term derived from Greek, and it means a death without any suffering. According to the Brazilian Arouca Law (Article 14, Chapter IV, Paragraphs 1 and 2), an animal should undergo euthanasia, in strict compliance with the requirements of each species, when the experiment ends or during any phase of the experiment, wherever this procedure is recommended and/or whenever serious suffering occurs. If the animal does not undergo euthanasia after the intervention it may leave the vivarium and be assigned to suitable people or to the animal protection bodies, duly legalized [ 1 ].

Euthanasia procedures must result in instant loss of consciousness which leads to respiratory or cardiac arrest as well as to complete brain function impairment. Another important aspect of this procedure is calm handling of the animal while taking it out of its enclosure, to reduce its distress, suffering, anxiety and fear. In every research project, the study design should include the details of the appropriate endpoints of these experimental animals, and also the methods that will be adopted. It is important to determine the appropriate method of euthanasia for the animal being used. Another important point is that, after completing the euthanasia procedure, the animal’s death should be absolutely confirmed before discarding their bodies [ 87 , 89 ].

Relevance of animal experimentations and possible alternatives

Relevance of animal experiments and their adverse effects on human health.

One important concern is whether human diseases, when inflicted on experimental animals, adequately mimic the progressions of the disease and the treatment responses observed in humans. Several research articles have made comparisons between human and animal data, and indicated that the results of animals’ research could not always be reliably replicated in clinical research among humans. The latest systematic reviews about the treatment of different clinical conditions including neurology, vascular diseases and others, have established that the results of animal studies cannot properly predict human outcomes [ 59 , 90 ].

At present, the reliability of animal experiments for extrapolation to human health is questionable. Harmful effects may occur in humans because of misleading results from research conducted on animals. For instance, during the late fifties, a sedative drug, thalidomide, was prescribed for pregnant women, but some of the women using that drug gave birth to babies lacking limbs or with foreshortened limbs, a condition called phocomelia. When thalidomide had been tested on almost all animal models such as rats, mice, rabbits, dogs, cats, hamsters, armadillos, ferrets, swine, guinea pig, etc., this teratogenic effect was observed only occasionally [ 91 ]. Similarly, in 2006, the compound TGN 1412 was designed as an immunomodulatory drug, but when it was injected into six human volunteer, serious adverse reactions were observed resulting from a deadly cytokine storm that in turn led to disastrous systemic organ failure. TGN 1412 had been tested successfully in rats, mice, rabbits, and non-human primates [ 92 ]. Moreover, Bailey (2008) reported 90 HIV vaccines that had successful trial results in animals but which failed in human beings [ 93 ]. Moreover, in Parkinson disease, many therapeutic options that have shown promising results in rats and non-human primate models have proved harmful in humans. Hence, to analyze the relevance of animal research to human health, the efficacy of animal experimentation should be examined systematically [ 94 , 95 ]. At the same time, the development of hyperoxaluria and renal failure (up to dialysis) after ileal-jejunal bypass was unexpected because this procedure was not preliminarily evaluated on an animal model [ 96 ].

Several factors play a role in the extrapolation of animal-derived data to humans, such as environmental conditions and physiological parameters related to stress, age of the experimental animals, etc. These factors could switch on or off genes in the animal models that are specific to species and/or strains. All these observations challenge the reliability and suitability of animal experimentation as well as its objectives with respect to human health [ 76 , 92 ].

ALTERNATIVE TO ANIMAL EXPERIMENTATION/DEVELOPMENT OF NEW PRODUCTS AND TECHNIQUES TO AVOID ANIMAL SACRIFICE IN RESEARCH

Certainly, in vivo animal experimentation has significantly contributed to the development of biological and biomedical research. However it has the limitations of strict ethical issues and high production cost. Some scientists consider animal testing an ineffective and immoral practice and therefore prefer alternative techniques to be used instead of animal experimentation. These alternative methods involve in vitro experiments and ex vivo models like cell and tissue cultures, use of plants and vegetables, non-invasive human clinical studies, use of corpses for studies, use of microorganisms or other simpler organism like shrimps and water flea larvae, physicochemical techniques, educational software, computer simulations, mathematical models and nanotechnology [ 97 ]. These methods and techniques are cost-effective and could efficiently replace animal models. They could therefore, contribute to animal welfare and to the development of new therapies that can identify the therapeutics and related complications at an early stage [ 1 ].

The National Research Council (UK) suggested a shift from the animal models toward computational models, as well as high-content and high-throughput in vitro methods. Their reports highlighted that these alternative methods could produce predictive data more affordably, accurately and quickly than the traditional in vivo or experimental animal methods [ 98 ].

Increasingly, scientists and the review boards have to assess whether addressing a research question using the applied techniques of advanced genetics, molecular, computational and cell biology, and biochemistry could be used to replace animal experiments [ 59 ]. It must be remembered that each alternative method must be first validated and then registered in dedicated databases.

An additional relevant concern is how precisely animal data can mirror relevant epigenetic changes and human genetic variability. Langley and his colleagues have highlighted some of the examples of existing and some emerging non-animal based research methods in the advanced fields of neurology, orthodontics, infectious diseases, immunology, endocrine, pulmonology, obstetrics, metabolism and cardiology [ 99 ].

IN SILICO SIMULATIONS AND INFORMATICS

Several computer models have been built to study cardiovascular risk and atherosclerotic plaque build-up, to model human metabolism, to evaluate drug toxicity and to address other questions that were previously approached by testing in animals [ 100 ].

Computer simulations can potentially decrease the number of experiments required for a research project, however simulations cannot completely replace laboratory experiments. Unfortunately, not all the principles regulating biological systems are known, and computer simulation provide only an estimation of possible effects due to the limitations of computer models in comparison with complex human tissues. However, simulation and bio-informatics are now considered essential in all fields of science for their efficiency in using the existing knowledge for further experimental designs [ 76 ].

At present, biological macromolecules are regularly simulated at various levels of detail, to predict their response and behavior under certain physical conditions, chemical exposures and stimulations. Computational and bioinformatic simulations have significantly reduced the number of animals sacrificed during drug discovery by short listing potential candidate molecules for a drug. Likewise, computer simulations have decreased the number of animal experiments required in other areas of biological science by efficiently using the existing knowledge. Moreover, the development of high definition 3D computer models for anatomy with enhanced level of detail, it may make it possible to reduce or eliminate the need for animal dissection during teaching [ 101 , 102 ].

3D CELL-CULTURE MODELS AND ORGANS-ON-CHIPS

In the current scenario of rapid advancement in the life sciences, certain tissue models can be built using 3D cell culture technology. Indeed, there are some organs on micro-scale chip models used for mimicking the human body environment. 3D models of multiple organ systems such as heart, liver, skin, muscle, testis, brain, gut, bone marrow, lungs and kidney, in addition to individual organs, have been created in microfluidic channels, re-creating the physiological chemical and physical microenvironments of the body [ 103 ]. These emerging techniques, such as the biomedical/biological microelectromechanical system (Bio-MEMS) or lab-on-a-chip (LOC) and micro total analysis systems (lTAS) will, in the future, be a useful substitute for animal experimentation in commercial laboratories in the biotechnology, environmental safety, chemistry and pharmaceutical industries. For 3D cell culture modeling, cells are grown in 3D spheroids or aggregates with the help of a scaffold or matrix, or sometimes using a scaffold-free method. The 3D cell culture modeling conditions can be altered to add proteins and other factors that are found in a tumor microenvironment, for example, or in particular tissues. These matrices contain extracellular matrix components such as proteins, glycoconjugates and glycosaminoglycans that allow for cell communication, cell to cell contact and the activation of signaling pathways in such a way that the morphological and functional differentiation of these cells can accurately mimic their environment in vivo . This methodology, in time, will bridge the gap between in vivo and in vitro drug screening, decreasing the utilization of animal models during research [ 104 ].

ALTERNATIVES TO MICROBIAL CULTURE MEDIA AND SERUM-FREE ANIMAL CELL CULTURES

There are moves to reduce the use of animal derived products in many areas of biotechnology. Microbial culture media peptones are mostly made by the proteolysis of farmed animal meat. However, nowadays, various suppliers provide peptones extracted from yeast and plants. Although the costs of these plant-extracted peptones are the same as those of animal peptones, plant peptones are more environmentally favorable since less plant material and water are required for them to grow, compared with the food grain and fodder needed for cattle that are slaughtered for animal peptone production [ 105 ].

Human cell culture is often carried out in a medium that contains fetal calf serum, the production of which involves animal (cow) sacrifice or suffering. In fact, living pregnant cows are used and their fetuses removed to harvest the serum from the fetal blood. Fetal calf serum is used because it is a natural medium rich in all the required nutrients and significantly increases the chances of successful cell growth in culture. Scientists are striving to identify the factors and nutrients required for the growth of various types of cells, with a view to eliminating the use of calf serum. At present, most cell lines could be cultured in a chemically-synthesized medium without using animal products. Furthermore, data from chemically-synthesized media experiments may have better reproducibility than those using animal serum media, since the composition of animal serum does change from batch to batch on the basis of animals’ gender, age, health and genetic background [ 76 ].

ALTERNATIVES TO ANIMAL-DERIVED ANTIBODIES

Animal friendly affinity reagents may act as an alternative to antibodies produced, thereby removing the need for animal immunization. Typically, these antibodies are obtained in vitro by yeast, phage or ribosome display. In a recent review, a comparative analysis between animal friendly affinity reagents and animal derived-antibodies showed that the affinity reagents have superior quality, are relatively less time consuming, have more reproducibility and are more reliable and are cost-effective [ 106 , 107 ].

Conclusions

Animal experimentation led to great advancement in biological and biomedical sciences and contributed to the discovery of many drugs and treatment options. However, such experimentation may cause harm, pain and distress to the animals involved. Therefore, to perform animal experimentations, certain ethical rules and laws must be strictly followed and there should be proper justification for using animals in research projects. Furthermore, during animal experimentation the 4 Rs principles of reduction, refinement, replacement and responsibility must be followed by the researchers. Moreover, before beginning a research project, experiments should be thoroughly planned and well-designed, and should avoid unnecessary use of animals. The reliability and reproducibility of animal experiments should also be considered. Whenever possible, alternative methods to animal experimentation should be adopted, such as in vitro experimentation, cadaveric studies, and computer simulations.

While much progress has been made on reducing animal experimentation there is a need for greater awareness of alternatives to animal experiments among scientists and easier access to advanced modeling technologies. Greater research is needed to define a roadmap that will lead to the elimination of all unnecessary animal experimentation and provide a framework for adoption of reliable alternative methodologies in biomedical research.

Acknowledgements

This research was funded by the Provincia Autonoma di Bolzano in the framework of LP 15/2020 (dgp 3174/2021).

Conflicts of interest statement

Authors declare no conflict of interest.

Author's contributions

MB: study conception, editing and critical revision of the manuscript; AKK, DP, GH, RB, Paul S, Peter S, RM, BF, NC, SM, LL, DD, GMT, MCE, MD, SM, Daniele M, GB, AD, KD, MCM, TB, MS, STC, Donald M, AM, AB, KLH, MK, LS, LL, GF: literature search, editing and critical revision of the manuscript. All authors have read and approved the final manuscript.

Contributor Information

INTERNATIONAL BIOETHICS STUDY GROUP : Derek Pheby , Gary Henehan , Richard Brown , Paul Sieving , Peter Sykora , Robert Marks , Benedetto Falsini , Natale Capodicasa , Stanislav Miertus , Lorenzo Lorusso , Gianluca Martino Tartaglia , Mahmut Cerkez Ergoren , Munis Dundar , Sandro Michelini , Daniele Malacarne , Tommaso Beccari , Michele Samaja , Matteo Bertelli , Donald Martin , Assunta Morresi , Ariola Bacu , Karen L. Herbst , Mykhaylo Kapustin , Liborio Stuppia , Ludovica Lumer , and Giampietro Farronato

Animal testing IELTS essay

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IELTS animal testing essay: Some people think that it is acceptable to use animals in medical research for the benefits of human beings, while other people argue that it is wrong.

Over centuries humans have experimented with many different chemicals, products, and processes, with the final aim of bettering our conditions. Testing products on animals most likely dates back centuries, however, in modern society it is a controversial point. Below is an outline of circumstances when it could be considered acceptable and unacceptable.

Firstly, it is clear that major advances in fighting disease, viruses and illnesses would not have been made without testing products on animals. This is because it is inhumane to test the products on healthy human beings, likewise using computer modelling to predict reactions is only a recent possibility and still not as reliable as testing on animals. Therefore without experiments on animals, breakthroughs in medicine would have been impossible, and most would agree the price paid has been worth it.

Conversely, it could be argued that medical research carried out for mere cosmetic ends is undoubtedly not worth the lives of innocent animals. This is largely for two reasons, firstly a large body of research is said to have been built up previously from past experiments, and secondly there are alternatives such as dermatological testing or using natural ingredients.

For example, retail chains such as Lush and The Body Shop have both made fortunes by positioning themselves as natural solutions against animal testing. Therefore due to the end rationale for testing on animals, and the alternatives available, it is clear it is completely unjustifiable in this situation.

To conclude animal welfare can be side-stepped when the situation is threatening humans and computer alternatives are simply too premature. Nevertheless, when the research has rather fickle motives and viable alternatives do exist, in these cases the loss of animal's lives in inexcusable.

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Animal Testing Essay

Posted by David S. Wills | Oct 21, 2022 | Model Essays | 0

There is a wide range of topics used in the IELTS writing test and many of them overlap. Today, we are going to look at a question that falls between the topics of animals and ethics and science. It will require you to write an animal testing essay .

In this article, I will analyse the question for you, give you some pointers on useful language, and then show you my own sample band 9 answer.

The Task: Animal Testing

Here is a question that appeared in the IELTS exam several years ago:

Some people claim that it is acceptable to use animals in medical research for the benefit of human beings, while other people argue that it is wrong. Discuss both views and give your opinion.

(Note that questions can be re-used or re-written, so it is possible that you might see this recycled in the future.)

This is a “discuss both views” question , so your task is ultimately to do three things:

• Explain why some people think animal testing is acceptable
• Explain why some people think animal testing is unacceptable
• Give your opinion

Even if you feel really strongly that it is wrong, for example, you still need to explain the opposing view. You don’t need to give a balanced answer , but you do need to acknowledge both sides of the debate. This is important for Task Response.

Planning your Answer

I almost always write a four-paragraph essay for my sample band 9 answers but today I’m going to write five. It could easily have been four paragraphs but I wanted to separate my anti-animal testing arguments into two separate paragraphs for better organisation. (You can read about 4- vs 5-paragraph essay structures here .)

My essay is going to look like this:

When it comes to a task 2 introduction , please make sure that you have a clear outline sentence and also that your opinion (if one is required) is stated clearly.

Body paragraph 1 will act as a sort of concession paragraph , so it will be imperative that I make it clear that this is not my opinion but rather what some other people think. If I fail to do this, then the reader might be confused.

The ideas in body paragraphs 2 and 3 will be separated but could also have been condensed into two paragraphs. However, I felt that for this topic it was a little more effective to split them. It also made my argument slightly more persuasive.

For the conclusion , I will be careful not to repeat myself too much and instead just summarise and reaffirm my stance.

Language for an Animal Testing Essay

The topic of animal testing is obviously controversial and so people will have different ideas. What you say will be largely based upon your own opinions. However, keep in mind that it covers those three topics I mentioned:

You don’t really need to know a lot about each, but it definitely would have some benefit if you knew a little about these areas and had some good vocabulary to use. I wrote about the IELTS topic of animals here , and there is plenty of good vocabulary that you can borrow. You can also search “animals” in the search bar at the top of the page.

I also recommend that you read and listen on issues that are related to IELTS topics like this. I particularly recommend the SYSK podcast episode on animal testing, which I think it is informative and accessible. You may learn some good language and get some inspiration for what you could write in your own animal testing essay. Other sources include this argument against animal testing by PETA and this one in favour of it by Stanford.

Language for Contentious Issues

In my essay, I will use the following phrases, which could be modified and applied to other contentious issues. I will put the specific language in brackets, so that you could swap it out when discussing other topics:

• [animal testing] has been fiercely debated due to the ethical problems inherent in this area of [science]
• The people who believe that [animal testing] is necessary tend to say…
• this is wrong for several reasons
• [animal testing] is not as helpful in [developing medicines] as people think
• There are many other reasons why [experimenting with animals] is wrong
• it is grossly unethical to [subject these creatures to painful and demeaning experiences]
• people may argue that there are benefits that come from [experimenting on animals], but in fact there is no good reason to continue doing this

You can try using and modifying these phrases in your own practice essays. If you want an expert to correct them for you, try my IELTS writing correction service .

Language about Animal Testing

The following phrases will also appear in my essay and can be used for talking about animal testing:

• this area of science
• animal testing should be banned
• testing medicines before using them on human beings
• figure out the cures to many serious illnesses
• Medicines that work on animals do not always work on humans
• if scientists give a mouse diabetes and then try various drugs to cure the problem
• subject these creatures to painful and demeaning experiences
• They are sentient beings
• subjected to cruel and often unnecessary experiments
• harmful both to humans and animals

It is also important to avoid repetition and that means finding ways to say “animal testing” without repeating the say words over and over. You could say:

• testing on animals
• experimenting on animals
• subjecting animals to medical experiments
• using animals in experiments

Again, it would be helpful to read articles and listen to podcasts on this topic in order to improve your vocabulary.

Sample Band 9 Answer

Over the past few decades, animal testing has been fiercely debated due to the ethical problems inherent in this area of science. This essay will look at both sides of the debate, before concluding that animal testing should be banned.

The people who believe that animal testing is necessary tend to say that there are serious benefits to humanity, such as testing medicines before using them on human beings. They believe that this will help to figure out the cures to many serious illnesses, which will make the world a better place for humans. However, this is wrong for several reasons.

Firstly, animal testing is not as helpful in developing medicines as people think. Medicines that work on animals do not always work on humans, and vice versa. As such, these trials are not just unnecessary but also profoundly unhelpful. For example, if scientists give a mouse diabetes and then try various drugs to cure the problem, they may find that there are twelve drugs that do not work on the mouse. However, maybe one of those drugs would have worked on a human. As such, animal testing would have caused more problems than it solved.

There are many other reasons why experimenting with animals is wrong. Perhaps most importantly, it is grossly unethical to subject these creatures to painful and demeaning experiences for the benefit of humanity. Animals do not exist for the benefit of people. They are sentient beings that deserve better than to be caged and subjected to cruel and often unnecessary experiments.

In conclusion, people may argue that there are benefits that come from experimenting on animals, but in fact there is no good reason to continue doing this. At best, these experiments are useless and at worst they are unethical and harmful both to humans and animals.

Final Notes

You can see that I have carefully crafted an argument that is strong. You may not agree with it, but it is hard to deny my points, which makes it effective in terms of Task Response. The structure is also solid and the ideas were well connected, making it very good in terms of Coherence and Cohesion . Note the inclusion of realistic and interesting ideas as well as concrete examples. My explanation of testing on mice was particularly effective here. It is better than giving some vague or unexplained idea.

About The Author

David S. Wills

David S. Wills is the author of Scientologist! William S. Burroughs and the 'Weird Cult' and the founder/editor of Beatdom literary journal. He lives and works in rural Cambodia and loves to travel. He has worked as an IELTS tutor since 2010, has completed both TEFL and CELTA courses, and has a certificate from Cambridge for Teaching Writing. David has worked in many different countries, and for several years designed a writing course for the University of Worcester. In 2018, he wrote the popular IELTS handbook, Grammar for IELTS Writing and he has since written two other books about IELTS. His other IELTS website is called IELTS Teaching.

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Ielts writing task 2 sample 731 - nowadays animal experiments are widely used to develop new medicines, ielts writing task 2/ ielts essay:, nowadays animal experiments are widely used to develop new medicines and to test the safety of other products. some people argue that these experiments should be banned because it is morally wrong to cause animals to suffer, while others are in favour of them because of their benefits to humanity..

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Home / Essay Samples / Social Issues / Animal Testing / Personal Statement on the Topic About Animal Testing

Personal Statement on the Topic About Animal Testing

• Category: Social Issues , Science
• Topic: Animal Testing , Animals , Experiment

Pages: 2 (1030 words)

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