Poster Presentation Australian & New Zealand Obesity Society 2014 Annual Scientific Meeting

Food "Micro-Intake" events: a common but underexplored aspect of ingestive behaviour in model animals (#174)

John R.B. Lighton 1
  1. Sable Systems International, Inc, Las Vegas, NV, United States

Measurement of food intake by experimental animals is typically performed gravimetrically. The mass of a food hopper is monitored, and the abrupt increase in the variance of the hopper mass that signals an intake event is detected. The decrease in hopper mass following the re-establishment of mass stability equals the mass of food removed. However, the low mass resolution of most intake monitoring systems (ca. 0.01-0.02g) dictates the smallest intake event that can be detected. I show, using a Sable Systems Promethion high resolution (0.002g) food intake monitoring system, that many intake bouts occur below the detection threshold of conventional food intake monitoring systems. These “micro-intake” events typically last for < 2.5 min, with some lasting < 1 min and corresponding to an intake amount < 0.01g. The validity of these events is verified by statistical comparison of the hopper mass prior to and after the intake bout. Although the contribution of “micro-intake” events to total food intake amounts is relatively minor, each such event corresponds to initiation of a feeding stimulus followed by its rapid satiation. “Micro-intake” events can comprise 10-20% of total intake events in male C57BL/6 mice, and cannot be ignored if a complete understanding of model animal feeding behavior is desired.