An open-source device for measuring food intake and operant behavior in rodent home-cages
Abstract
Feeding is critical for survival and disruption in the mechanisms that govern food intake underlie disorders such as obesity and anorexia nervosa. It is important to understand both food intake and food motivation to reveal mechanisms underlying feeding disorders. Operant behavioral testing can be used to measure the motivational component to feeding, but most food intake monitoring systems do not measure operant behavior. Here, we present a new solution for monitoring both food intake and motivation in rodent home-cages: The Feeding Experimentation Device version 3 (FED3). FED3 measures food intake and operant behavior in rodent home-cages, enabling longitudinal studies of feeding behavior with minimal experimenter intervention. It has a programmable output for synchronizing behavior with optogenetic stimulation or neural recordings. Finally, FED3 design files are open-source and freely available, allowing researchers to modify FED3 to suit their needs.
Data availability
The FED3 device is open-source and design files and code are freely available online at: https://github.com/KravitzLabDevices/FED3. In addition, we have made all data and analysis code for this paper available at https://osf.io/hwxgv/.
Article and author information
Author details
Funding
National Institutes of Health (ZIADK075099)
- Bridget Alexandra Matikainen-Ankney
- Mohamed Ali
- Amy K Sutton
- Katrina P Nguyen
- Michael J Krashes
- Alexxai V Kravitz
National Institutes of Health (DA049924)
- Meaghan C Creed
Whitehall Foundation (2017-12-54)
- Meaghan C Creed
Rita Allen Foundation
- Meaghan C Creed
Brain and Behavior Research Foundation
- Meaghan C Creed
- Alexxai V Kravitz
Washington University Diabetes Research Center
- Bridget Alexandra Matikainen-Ankney
- Thomas Earnest
- Eric Casey
- Alex A Legaria
- Alexxai V Kravitz
Washington University Nutrition Obesity Research Center
- Kia M Barclay
- Makenzie R Norris
- Yu-Hsuan Chang
- Meaghan C Creed
National Institutes of Health (R00DA038725)
- Ream Al-Hasani
National Institutes of Health (R01NS117899)
- Jordan G McCall
McDonnell Center for Cellular and Molecular Neurobiology
- Bridget Alexandra Matikainen-Ankney
National Health and Medical Research Council of Australia
- Zane B Andrews
National Institutes of Health (DK108742)
- Bridget Alexandra Matikainen-Ankney
National Institutes of Health (DA047127)
- Meaghan C Creed
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: 166 C57Bl/6 mice were housed in a 12-hour light/dark cycle with ad libitum access to food and water except where described. Mice were provided laboratory chow diet (5001 Rodent Diet; Lab Supply, Fort Worth, Texas). All procedures were approved by the Animal Care and Use Committee at Washington University in St Louis, the National Institutes of Health, Williams College, Virginia Tech and Monash University.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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