Experimental models and tools in animal research: From classical approaches to emerging trends

Abstract

From invertebrates like fruit flies to vertebrates such as mice and aquatic organisms, animal models have long been central to biological discovery. Despite ethical debates and growing regulatory constraints, animal research remains a cornerstone for understanding pathophysiology and developing new therapies for both humans and animals. Significant advances have refined these models, improving their relevance in scientific research and experimental education. However, the emergence of innovative systems, including computer simulations, organ-on-a-chip technologies, and genetically modified organisms, offers promising alternatives that can complement or, in some cases, replace animal experimentation. These tools accelerate scientific progress, enhance educational training, and improve the translation of results to human biology. Yet, systematic reviews have revealed discrepancies between animal and human responses, calling into question the predictive validity of traditional models. This ongoing debate highlights the need for a balanced integration of classical and emerging approaches to strengthen scientific reliability, educational value, and ethical standards. This review aims to provide an overview of experimental models, contrasting classical and novel systems, and to discuss their applications, limitations, and the evolving regulatory frameworks that guide their use in modern research and education.

Keywords: Animal models- Education- Animal research- Emerging models- Classical models- Animal Ethics