What is a laboratory rat? - briefly
A laboratory rat is a domesticated rodent, usually «Rattus norvegicus», bred and kept under standardized conditions for experimental use. It serves as a reproducible model for investigations into genetics, disease pathways, and drug effects.
What is a laboratory rat? - in detail
The laboratory rat is a domesticated rodent specifically bred for scientific investigation. It belongs to the species Rattus norvegicus and is maintained under controlled genetic, environmental, and health conditions to ensure reproducibility of experimental results. Standard breeding programs produce genetically homogeneous lines, known as strains, that exhibit predictable physiological and behavioral traits.
Commonly employed strains include:
- Sprague‑Dawley: outbred, large size, rapid growth, widely used in toxicology and pharmacology.
- Wistar: outbred, calm temperament, suitable for neurobehavioral studies.
- Long‑Evans: pigmented, preferred for vision research and behavioral assays.
- Fischer 344: inbred, short lifespan, employed in aging and oncology investigations.
- Brown Norway: inbred, high susceptibility to certain metabolic disorders, used in diabetes research.
Physiological characteristics of the research rat provide relevance to human biology. Adult individuals weigh 250–350 g, possess a lifespan of 2–3 years, and share organ systems, metabolic pathways, and genome organization with humans. Their immune response, endocrine regulation, and central nervous system architecture enable modeling of diseases ranging from cardiovascular dysfunction to neurodegenerative conditions.
Housing protocols mandate temperature control (20–24 °C), relative humidity (40–60 %), a 12‑hour light/dark cycle, and enrichment items such as nesting material and tunnels. Nutritional regimens supply standardized chow, water ad libitum, and, when required, calibrated dietary modifications. Health monitoring includes regular screening for pathogens, parasitic infestations, and genetic drift to preserve colony integrity.
Regulatory frameworks governing the use of laboratory rats encompass institutional animal care and use committees, national legislation, and international guidelines such as the ARRIVE principles. These standards obligate researchers to justify animal numbers, apply refinement techniques, and implement humane endpoints. Compliance ensures ethical responsibility while preserving scientific validity.
«The laboratory rat is the most widely used mammalian model in biomedical research», a statement frequently cited in methodological reviews, underscores the animal’s central role in advancing medical knowledge. Detailed understanding of its genetics, physiology, and husbandry is essential for designing robust experiments and interpreting translational outcomes.