Effects of Rodent Thermoregulation on Animal Models in the Research Environment.

To best promote animal wellbeing and the efficacy of biomedical models, scientific, husbandry, and veterinary professionalsmust consider the mechanisms, influences, and outcomes of rodent thermoregulation in contemporary research environments.Over the last 2 decades, numerous studies have shown that laboratory mice and rats prefer temperatures that are several degrees warmer than the environments in which they typically are housed within biomedical facilities. Physiologic changes torodents that are cage-housed under standard temperatures (20 to 26 °C) are attributed to 'cold stress' and include alterationsin metabolism, cardiovascular parameters, respiration, and immunologic function. This review article describes commonbehavioral and physiologic adaptations of laboratory mice and rats to cold stress within modern vivaria, with emphasis onenvironmental enrichment and effects of anesthesia and procedural support efforts. In addition, potential interventions andoutcomes for rodents are presented, relative to the importance of repeating and reproducing experiments involving laboratoryrodent research models of human disease.