Integrated Thermal Comfort for Your Animals. The SMART System is an IVC rack system that offers 10 Optimice¨ laboratory heated mouse cage stations with heated comfort under a portion of the cage floor. The mice thermoneutral zone is between 26 and 34 degrees Celsius; however typical housing rooms are kept between 21 and 26 C. Cold-stressed mice in any rodent cage develop dramatic changes in physiology, behavior, and immune function and skew experimental results. Robust mice cope by using nesting material, but many mice benefit from having thermal support. The SMART System, thermal comfort USB powered rack, includes 10 Optimice heated mouse cage stations, with two USB powering ports per station