SmartHomeCage: a platform for automation of rodent behavior monitoring at homecages

Abstract

We have developed a SmartHomeCage system that allow for insertion of normal rodent cages to monitor animal's behaviors in its homecage with bedding, food and water for days. Each apparatus is comprised of multiple sensors and up to 16 apparatuses can be simultaneously operated by one PC. Parameters measured include sleep/wake states, locomotion (traveling distance and speed), rearing, movement patterns and rotations. For validating the system, we showed that cocaine (30 mg/kg, ip) produced an increase in activity including distance traveled and rearing. The nociceptin receptor agonist SR 14150 (10 mg/kg, ip) that was previously shown to induce hypolocomotion produced a decrease in activity. Using a dark box inserted in the normal cage, we were able to assess the anxiolytic effect of diazepam (3mg/kg, i.p.), as indicated by an increased latency of first entry to the dark box and increased the transition number between light and dark compartments. In pilot studies through collaboration with universities, we showed this system is sensitive enough to quantify mouse behavioral changes following experimental spinal injury or middle cerebral artery occlusion. Sleep/wake state automated classification using the SmartHomeCage will be further validated by comparing with simultaneous EEG recordings. This higher throughput behavioral monitoring system for behavioral phenotype of transgenic and gene knockout mice are currently underway.