title: Death-associated odors induce stress in zebrafish.
abstract: Living animals exploit information released from dead animals to conduct adaptive biological responses. For instance, a recently published study has shown that avoidance behavior is triggered by death-associated odors in zebrafish. Stress can clearly act as an adaptive response that allows an organism to deal with an imminent threat. However, it has not been demonstrated whether these chemical cues are stressful for fish. Here, we confirmed that dead zebrafish scents induce defensive behavior in live conspecifics. Additionally, we show for the first time in fish that these scents increase cortisol in conspecifics. To reach this conclusion, firstly, we exposed zebrafish to multi-sensorial cues (e.g., visual, tactile, chemical cues) from dead conspecifics that displayed defensive behaviors and increased cortisol. Also, when we limited zebrafish to chemical cues from dead conspecifics, similar responses arose. These responses coincide with the decaying destruction of epidermal cells, indicating that defensive and stress responses could take place as an effect of substances emanating from decaying flesh, as well as alarm substance released due to rupture of epidermal cells. Taken together, these results illustrate that living zebrafish utilize cues from dead conspecific to avoid or to cope with danger and ensure survival.
authors.affiliation: Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria, Campus Universitário - Camobi, CEP 97105-900 Santa Maria, RS, Brazil.
authors.forename: Thiago Acosta
authors.initials: TA
authors.lastname: Oliveira
authors.affiliation: Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria, Campus Universitário - Camobi, CEP 97105-900 Santa Maria, RS, Brazil.
authors.forename: Gessi
authors.initials: G
authors.lastname: Koakoski
authors.affiliation: Universidade de Passo Fundo (UPF), Curso de Medicina Veterinária, Campus I, Bairro São José, Caixa Postal 611, CEP 99001-970 Passo Fundo, RS, Brazil.
authors.forename: Adriana Costa
authors.initials: AC
authors.lastname: da Motta
authors.affiliation: Laboratório de Psicofarmacologia e Comportamento (LAPCOM), Universidade Comunitária da Região de Chapecó, Rua Sen. Attílio Fontana, 591 E, Efapi, 89809-000 SC, Brazil.
authors.forename: Angelo Luis
authors.initials: AL
authors.lastname: Piato
authors.affiliation: Departamento de Fisiologia, Instituto de Biociências, UNESP - Univ. Estadual Paulista, CAUNESP - Centro de Aquicultura da UNESP, Campus de Botucatu - Rubião Jr., 18618-970 Botucatu, São Paulo, Brazil.
authors.forename: Rodrigo Egydio
authors.initials: RE
authors.lastname: Barreto
authors.affiliation: Departamento de Fisiologia, Instituto de Biociências, UNESP - Univ. Estadual Paulista, CAUNESP - Centro de Aquicultura da UNESP, Campus de Botucatu - Rubião Jr., 18618-970 Botucatu, São Paulo, Brazil.
authors.forename: Gilson Luiz
authors.initials: GL
authors.lastname: Volpato
authors.affiliation: Universidade de Passo Fundo (UPF), Curso de Medicina Veterinária, Campus I, Bairro São José, Caixa Postal 611, CEP 99001-970 Passo Fundo, RS, Brazil. Electronic address: lbarcellos@upf.br.
authors.forename: Leonardo José Gil
authors.initials: LJ
authors.lastname: Barcellos
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D003643:Death; D005260:Female; D006854:Hydrocortisone / Q000378:metabolism; D008297:Male; D009812:Odorants; D012677:Sensation / Q000502:physiology*; D012903:Smell / Q000502:physiology; D013315:Stress, Psychological / Q000139:chemically induced / Q000209:etiology* / Q000378:metabolism; D015027:Zebrafish / Q000502:physiology*
chemical_list: D006854:Hydrocortisone
keywords: Cortisol; Danio rerio; Freezing; Necrophobic behavior; Stress