{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T20:19:55Z","timestamp":1770149995752,"version":"3.49.0"},"reference-count":36,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,7]],"date-time":"2023-06-07T00:00:00Z","timestamp":1686096000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Research association","award":["DFG-FOR2591"],"award-info":[{"award-number":["DFG-FOR2591"]}]},{"name":"German Research association","award":["GZ: BA 7115\/1-2"],"award-info":[{"award-number":["GZ: BA 7115\/1-2"]}]},{"name":"German Research association","award":["CZ 215\/3-2"],"award-info":[{"award-number":["CZ 215\/3-2"]}]},{"name":"German Research association","award":["PO 681\/9-1"],"award-info":[{"award-number":["PO 681\/9-1"]}]},{"name":"German Research association","award":["PO 681\/9-2"],"award-info":[{"award-number":["PO 681\/9-2"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Animal research has always been crucial for various medical and scientific breakthroughs, providing information on disease mechanisms, genetic predisposition to diseases, and pharmacological treatment. However, the use of animals in medical research is a source of great controversy and ongoing debate in modern science. To ensure a high level of bioethics, new guidelines have been adopted by the EU, implementing the 3R principles to replace animal testing wherever possible, reduce the number of animals per experiment, and refine procedures to minimize stress and pain. Supporting these guidelines, this article proposes an improved approach for unobtrusive, continuous, and automated monitoring of the respiratory rate of laboratory rats. It uses the cyclical expansion and contraction of the rats\u2019 thorax\/abdominal region to determine this physiological parameter. In contrast to previous work, the focus is on unconstrained animals, which requires the algorithms to be especially robust to motion artifacts. To test the feasibility of the proposed approach, video material of multiple rats was recorded and evaluated. High agreement was obtained between RGB imaging and the reference method (respiratory rate derived from electrocardiography), which was reflected in a relative error of 5.46%. The current work shows that camera-based technologies are promising and relevant alternatives for monitoring the respiratory rate of unconstrained rats, contributing to the development of new alternatives for a continuous and objective assessment of animal welfare, and hereby guiding the way to modern and bioethical research.<\/jats:p>","DOI":"10.3390\/ani13121901","type":"journal-article","created":{"date-parts":[[2023,6,7]],"date-time":"2023-06-07T02:02:15Z","timestamp":1686103335000},"page":"1901","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Camera-Based Respiration Monitoring of Unconstrained Rodents"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-1481-2398","authenticated-orcid":false,"given":"Lukas","family":"Breuer","sequence":"first","affiliation":[{"name":"Department of Anesthesiology, Faculty of Medicine, RWTH Aachen University, Pauwelsstra\u00dfe 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0041-2879","authenticated-orcid":false,"given":"Lucas","family":"M\u00f6sch","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, Faculty of Medicine, RWTH Aachen University, Pauwelsstra\u00dfe 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9399-706X","authenticated-orcid":false,"given":"Janosch","family":"Kunczik","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, Faculty of Medicine, RWTH Aachen University, Pauwelsstra\u00dfe 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2705-4565","authenticated-orcid":false,"given":"Verena","family":"Buchecker","sequence":"additional","affiliation":[{"name":"Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University of Munich, K\u00f6niginstra\u00dfe 16, 80539 M\u00fcnchen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1506-0252","authenticated-orcid":false,"given":"Heidrun","family":"Potschka","sequence":"additional","affiliation":[{"name":"Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University of Munich, K\u00f6niginstra\u00dfe 16, 80539 M\u00fcnchen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7118-7728","authenticated-orcid":false,"given":"Michael","family":"Czaplik","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, Faculty of Medicine, RWTH Aachen University, Pauwelsstra\u00dfe 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1788-4562","authenticated-orcid":false,"given":"Carina Barbosa","family":"Pereira","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, Faculty of Medicine, RWTH Aachen University, Pauwelsstra\u00dfe 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"238","DOI":"10.3390\/ani3010238","article-title":"Animal experiments in biomedical research: A historical perspective","volume":"3","author":"Franco","year":"2013","journal-title":"Animals"},{"key":"ref_2","first-page":"33","article-title":"Directive 2010\/63\/EU of the European parliament and of the council of 22 September 2010 on the protection of animals used for scientific purposes","volume":"276","author":"Parliament","year":"2010","journal-title":"Off. 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