An open-source tool for automated analysis of breathing behaviors in common marmosets and rodents
Abstract
The respiratory system maintains homeostatic levels of oxygen (O2) and carbon dioxide (CO2) in the body through rapid and efficient regulation of breathing frequency and depth (tidal volume). The commonly used methods of analysing breathing data in behaving experimental animals are usually subjective, laborious, and time-consuming. To overcome these hurdles, we optimized an analysis toolkit for the unsupervised study of respiratory activities in animal subjects. Using this tool, we analyzed breathing behaviors of the common marmoset (Callithrix jacchus), a New World non-human primate model. Using Whole-body Plethysmography in room air as well as acute hypoxic (10% O2) and hypercapnic (6% CO2) conditions, we describe breathing behaviors in awake, freely behaving marmosets. Our data indicate that marmosets' exposure to acute hypoxia decreased metabolic rate and increased sigh rate. However, the hypoxic condition did not augment ventilation. Hypercapnia, on the other hand, increased both the frequency and depth (i.e., tidal volume) of breathing.
Data availability
All the code is available on the NGSC GitHub (https://github.com/NGSC-NINDS/Marm_Breathing_Bishop_et_al_2021). The data generated in Figures 3 - 6 are provided in the source files.
Article and author information
Author details
Funding
Intramural Research Program of the National Institutes of Health, NINDS and NIMH
- Shahriar SheikhBahaei
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Melissa Bates, University of Iowa, United States
Ethics
Animal experimentation: All experiments were performed in accordance with the National Institutes of Health Guide for the Care and Use of Laboratory Animals and were approved by the Animal Care and Use Committee of the Intramural Research Program of the National Institute of Mental Health and the Intramural Research Program of the National Institute of Neurological Disorders and Stroke.
Version history
- Preprint posted: July 29, 2020 (view preprint)
- Received: June 25, 2021
- Accepted: January 19, 2022
- Accepted Manuscript published: January 20, 2022 (version 1)
- Version of Record published: February 18, 2022 (version 2)
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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