ABSTRACT
Animals used in research, teaching, and testing are complex living creatures that respond to environmental parameters. Whether living in a tightly controlled internal environment or an outdoor environment subject to weather changes, animals, through their physiological and behavioral processes, will respond to various stressors in their environment. When attempting to control and minimize the effect of environmental variables on laboratory animals, the design and management of the research facility is paramount. The animal's environment consists of both the micro- and the macroenvironment. The macroenvironment must be maintained in a manner that will provide stable, comfortable, and clean living conditions for the animals. Appropriate lighting is crucial to an animal's physiology and behavior, and alterations in light cycle, intensity, or spectrum may lead to stress. Ensuring consistent, species-specific temperature and humidity in an animal room is critical for animal thermoregulation, to maintain normal physiology, and to promote natural behavioral tendencies.
