Feeding Experimentation Device (FED): Construction and Validation of an Open-source Device for Measuring Food Intake in Rodents

Abstract

Food intake measurements are essential for many research studies. Here, we provide a detailed description of a novel solution for measuring food intake in mice: the Feeding Experimentation Device (FED). FED is an open-source system that was designed to facilitate flexibility in food intake studies. Due to its compact and battery powered design, FED can be placed within standard home cages or other experimental equipment. Food intake measurements can also be synchronized with other equipment in real-time via FED's transistor-transistor logic (TTL) digital output, or in post-acquisition processing as FED timestamps every event with a real-time clock. When in use, a food pellet sits within FED's food well where it is monitored via an infrared beam. When the pellet is removed by the mouse, FED logs the timestamp onto its internal secure digital (SD) card and dispenses another pellet. FED can run for up to 5 days before it is necessary to charge the battery and refill the pellet hopper, minimizing human interference in data collection. Assembly of FED requires minimal engineering background, and off-the-shelf materials and electronics were prioritized in its construction. We also provide scripts for analysis of food intake and meal patterns. Finally, FED is open-source and all design and construction files are online, to facilitate modifications and improvements by other researchers. Video LinkThe video component of this article can be found at https://www.jove.com/video/55098/ Protocol NOTE: This protocol is written for components specifically named in the Table of Materials. While similar functionality can be achieved using other hardware, FED was programmed for the Arduino Pro microcontroller (henceforth termed: microcontroller) and listed accessories. Other microcontrollers may work equally well, but will require the user to modify the code to support them. Offline data analysis was coded using the Python programming language.

Effect of chronic vapor nicotine exposure on affective and cognitive behavior in male mice

“…Operant conditioning was performed using the Feeding Experimentation Device 3 (FED3) 27 – 29 . The FED3 is a small battery-powered operant device that dispenses pellet rewards ( e.g.…”

Effect of chronic vapor nicotine exposure on affective and cognitive behavior in male mice

“…Equipment and Setup Operant conditioning was performed using the Feeding Experimentation Device 3 (FED3) [27][28][29] . The FED3 is a small battery-powered operant device that dispenses pellet rewards (e.g., grain-based diet or sucrose) according to experimenter-designed programs.…”

Examining Cognitive Performance in Mice using the Open-Source Operant Feeding Device FED3

“…Here, we present a protocol for evaluating cognitive performance in mice using the Feeding Experimentation Device version 3 [49][50][51] that addresses many of these challenges (Figure 1). The FED3 is an open-source operant device that is suitable for use in a traditional mouse home-cage environment, reducing the influence of environment-induced stress on cognitive performance, while increasing the number of cognitive behavioral tests researchers can perform each week.…”