{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T09:55:27Z","timestamp":1768816527526,"version":"3.49.0"},"reference-count":50,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,15]],"date-time":"2023-06-15T00:00:00Z","timestamp":1686787200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005416","name":"Norwegian Research Council","doi-asserted-by":"publisher","award":["226060"],"award-info":[{"award-number":["226060"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005416","name":"Norwegian Research Council","doi-asserted-by":"publisher","award":["2018\/01584-0"],"award-info":[{"award-number":["2018\/01584-0"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001807","name":"S\u00e3o Paulo Research Foundation","doi-asserted-by":"publisher","award":["226060"],"award-info":[{"award-number":["226060"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001807","name":"S\u00e3o Paulo Research Foundation","doi-asserted-by":"publisher","award":["2018\/01584-0"],"award-info":[{"award-number":["2018\/01584-0"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>As fish welfare becomes a growing concern, it is important to ensure humane treatment during slaughter. This study aimed to assess the onset of unconsciousness in Atlantic halibut immersed in CO2-saturated seawater through electroencephalography (EEG). Of the 29 fish studied, 10 exhibited escape attempts, indicating aversion to CO2-saturated water despite its oxygenation. EEG signals showed four distinct phases: transitional, excitation (high amplitude\u2013high frequency), suppressed, and iso-electric phases. The onset of the suppressed phase, indicative of unconsciousness, occurred on average 258.8 \u00b1 46.2 s after immersion. The spectral analysis of the EEG signals showed a progressive decrease in median frequency, spectral edge frequency, and high frequency contribution, which corresponded to the gradual loss of consciousness. The study concludes that CO2-saturated water is not recommended for pre-slaughter handling of halibut due to the extended time required for the onset of unconsciousness and the observed aversive behaviour. Ensuring humane treatment during slaughter is important for addressing public concern and safeguarding fish welfare in all stages of production.<\/jats:p>","DOI":"10.3390\/ani13121993","type":"journal-article","created":{"date-parts":[[2023,6,15]],"date-time":"2023-06-15T01:32:57Z","timestamp":1686792777000},"page":"1993","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Pre-Slaughter Stunning of Farmed Atlantic Halibut in CO2-Saturated Seawater: Assessment of Unconsciousness by Electroencephalography (EEG)"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0522-5746","authenticated-orcid":false,"given":"Daniel Santiago","family":"Rucinque","sequence":"first","affiliation":[{"name":"Faculdade de Zootecnia e Engenharia de Alimentos, Laborat\u00f3rio de Aquicultura, Universidade de S\u00e3o Paulo, Av. Duque de Caxias Norte 222, S\u00e3o Paulo 13635-900, Brazil"}]},{"given":"Hans","family":"van de Vis","sequence":"additional","affiliation":[{"name":"Wageningen Livestock Research, P.O. Box 338, 6700 AH Wageningen, The Netherlands"}]},{"given":"Henny","family":"Reimert","sequence":"additional","affiliation":[{"name":"Wageningen Livestock Research, P.O. Box 338, 6700 AH Wageningen, The Netherlands"}]},{"given":"Bj\u00f8rn","family":"Roth","sequence":"additional","affiliation":[{"name":"Department of Processing Technology, Nofima, 4068 Stavanger, Norway"}]},{"given":"Atle","family":"Foss","sequence":"additional","affiliation":[{"name":"Akvaplan-niva, Fram Centre, 9296 Troms\u00f8, Norway"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3485-400X","authenticated-orcid":false,"given":"Cesar Augusto","family":"Taconeli","sequence":"additional","affiliation":[{"name":"Department of Statistics, Federal University of Paran\u00e1, Curitiba 81531-980, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4410-0818","authenticated-orcid":false,"given":"Marien","family":"Gerritzen","sequence":"additional","affiliation":[{"name":"Wageningen Livestock Research, P.O. 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