Rodent drinking behavior is used in numerous task designs, most commonly two-bottle choice tasks, to provide insight into the research question of interest. Typically, measuring the intake of fluids is done by weighing bottles over days, and while several tools have been developed to improve monitoring of drinking behaviors, most lack the temporal resolution that is necessary for analysis of licking microstructure. To address this, Nicholas Petersen, Marie Doyle, and colleagues have developed LIQ HD (Lick Instance Quantifier Home cage Device), a user-friendly tool that utilizes capacitive sensors to precisely detect licks. The system can be used long-term in the home cages of animals during two-bottle choice tasks, removing the need to weigh bottles, which may disturb animals. The system has a touchscreen controller and an easy-to-use GUI, and can be used in up to 18 cages (36 bottles) simultaneously controlled by one Arduino. Lick number/duration, drink preference, and bout microstructure is tracked on a minute-to-minute timescale, with data from all cages logged to a single SD card. Arduino code, 3D print design files, and a tutorial video on how to build the system can be found on GitHub.
This research tool was created by your colleagues. Please acknowledge the Principal Investigator, cite the article in which the tool was described, and include an RRID in the Materials and Methods of your future publications. RRID:SCR_023802