A Comprehensive Review of Laboratory Animals Use in Biomedical Research: Welfare Concerns and Alternative Approaches

Mahendra Pal^1, , Tesfaye Rebuma², Alemayehu Bekele³, Ravindra Zende⁴, Aishwarya Nair⁴ and Dhwani Upadhyay⁵

¹Narayan Consultancy of Veterinary Public Health and Microbiology, B-103, Sapphire Lifestyle, Bharuch - 392 012, Gujarat, India

²Shaggar City Administration, Sebeta Sub-City Agricultural office, Sebeta, Oromia Region, Ethiopia

³Wallaga University, School of Veterinary Medicine, Department of Clinical Studies, Nekemte, Oromia, Ethiopia

⁴Department of Veterinary Public Health and Epidemiology, College of Veterinary Science, Parel, Mumbai, India

⁵Department of Life Sciences, Parul Institute of Applied Sciences, Parul University, Vadodara, Gujarat, India

Cite this paper:
Mahendra Pal, Tesfaye Rebuma, Alemayehu Bekele, Ravindra Zende, Aishwarya Nair and Dhwani Upadhyay. A Comprehensive Review of Laboratory Animals Use in Biomedical Research: Welfare Concerns and Alternative Approaches. American Journal of Biomedical Research. 2025; 13(2):29-36. doi: 10.12691/ajbr-13-2-2

Abstract

Laboratory animals have been central to biosciences research worldwide since decades. Animal welfare is increasingly being recognized as a critical component for both the ethical acceptability and scientific sustainability of such practices. Welfare entails preventing abuse, ensuring appropriate housing, feeding, disease prevention, treatment, and minimizing unnecessary discomfort or pain. The guiding principles of Replacement, Reduction, and Refinement (3Rs) not only improve welfare but also enhance translational value by increasing the reliability of animal models. Researchers bear ethical and legal obligations to safeguard animal well-being, as minimizing distress also improves reproducibility of results. The capacity of animals to adapt to their environment and exercise control over their lives is essential to welfare. Accordingly, animal experiments should be undertaken only when no alternative exists, and only when potential benefits outweigh the expected harm. Globally, millions of vertebrates are used each year in research, teaching, and testing. Approximately, 70% are employed in drug development, vaccine production, cancer research, and related biological studies, while the remaining 30% serve diagnostic and educational purposes. Among them, mice and rats dominate, accounting for about 61% and 14%, respectively, with rabbits also contributing significantly, particularly in atherosclerosis studies. Together, these species represent more than 80% of all research animals within the European Union. Harmonization of global laws and regulations remains essential to balance ethical responsibility with scientific progress. By promoting the 3Rs, reducing discomfort, and aligning practices with societal expectations, research can advance while maintaining respect for the animals on which it relies.

Keywords:
Biomedical research Experimental models Laboratory animals Mice Rabbit Rat Welfare

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