Volumetric measure and lick count of liquid food intake of rats.
A simple and relatively inexpensive lick counter-volumeter is described which automatically records liquid intake and drinking behavior of rats. It counts lick contacts while accurately measuring the rate of volume intake in constant unit volumes. The unit volumes are adjustable over a wide range. For a unit volume on the order of 60 microliter, the precision was 1.2% over a range of withdrawal rates from 1 to 10 ml/min. The average lick volume of rats consuming a liquid food was systematically lower by 18% during the second meal following a 15 hr fast when compared to that of the first. This change in average lick volume appears to reflect a change in the rat's motivation to drink the liquid food.
D000818:Animals; D004327:Drinking Behavior; D004566:Electrodes; D009482:Neurophysiology / Q000295:instrumentation*; D051381:Rats