Laboratoriohiiret

Laboratoriohiiret, the Finnish term for laboratory rats, are rodents commonly used in scientific research due to their physiological similarity to humans, rapid reproductive cycle, and well‑characterized genetics. The species most frequently employed is the Norway rat (Rattus norvegicus), although the brown rat (Rattus norvegicus) and the springfield rat (Rattus rattus) also appear in niche studies. These animals serve as models for studies ranging from immunology and cancer biology to neurobehavioral science and pharmacology.

Historically, laboratory rats were first used in controlled experiments in the late 19th century. Their use expanded dramatically after World War II, coinciding with advances in molecular biology and the need for standardized animal models. Over the decades, specific inbred strains have been developed to reduce genetic variability, enabling reproducible results. Modern facilities maintain stringent environmental controls, feeding protocols, and enrichment practices to minimize confounding variables.

Ethical considerations surrounding laboratoriohiiret are governed by national and international regulations. In the European Union, Directive 2010/63/EU and the EU Animal Welfare Act establish requirements for housing, care, and use of animals in research. Researchers must justify the necessity of animal models, pursue the 3Rs—replacement, reduction, and refinement—and obtain approval from institutional animal ethics committees. Continuous efforts in alternative methods, such as organ-on-chip technologies, aim to reduce reliance on live animals while preserving scientific relevance.

In addition to research, laboratory rats contribute to toxicological testing, vaccine development, and veterinary medicine. Their longevity and well‑understood biology facilitate longitudinal studies, while their social nature allows for the exploration of complex behaviors. Despite growing alternatives, laboratoriohiiret remain essential for certain biomedical inquiries, provided that their use adheres to ethical and welfare standards.