title: Influence of environmental enrichment vs. time-of-day on behavioral repertoire of male albino Swiss mice.
abstract: Environmental enrichment (EE) is a non-pharmacological manipulation that promotes diverse forms of benefits in the central nervous system of captive animals. It is thought that EE influences animal behavior in a specie-(strain)-specific manner. Since rodents in general present different behaviors during distinct periods of the day, in this study we aimed to investigate the influence of time-of-day on behavioral repertoire of Swiss mice that reared in EE. Forty male Swiss mice (21days old) were housed in standard (SC) or enriched conditions (EC) for 60days. Behavioral assessments were conducted during the light phase (in presence of light) or dark phase (in absence of light) in the following tasks: open field, object recognition and elevated plus maze. First, we observed that the locomotor and exploratory activities are distinct between SC and EC groups only during the light phase. Second, we observed that "self-protective behaviors" were increased in EC group only when mice were tested during the light phase. However, "less defensive behaviors" were not affected by both housing conditions and time-of-day. Third, we showed that the performance of EE animals in object recognition task was improved in both light and dark conditions. Our findings highlight that EE-induced alterations in exploratory and emotional behaviors are just evident during light conditions. However, EE-induced cognitive benefits are remarkable even during dark conditions, when exploratory and emotional behaviors were similar between groups.
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. Electronic address: cassio.m.loss@gmail.com.
authors.forename: Cássio Morais
authors.initials: CM
authors.lastname: Loss
authors.affiliation: Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil. Electronic address: binder.luisa@gmail.com.
authors.forename: Luisa Bandeira
authors.initials: LB
authors.lastname: Binder
authors.affiliation: Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil. Electronic address: dudamuccini@hotmail.com.
authors.forename: Eduarda
authors.initials: E
authors.lastname: Muccini
authors.affiliation: Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil. Electronic address: wagnerberserk@gmail.com.
authors.forename: Wagner Carbolin
authors.initials: WC
authors.lastname: Martins
authors.affiliation: Departamento de Farmacologia, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil. Electronic address: paulofarm@gmail.com.
authors.forename: Paulo Alexandre
authors.initials: PA
authors.lastname: de Oliveira
authors.affiliation: Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Departamento de Ciências Básicas em Saúde, Faculdade de Medicina, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil. Electronic address: samuelvandresen@yahoo.com.br.
authors.forename: Samuel
authors.initials: S
authors.lastname: Vandresen-Filho
authors.affiliation: Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil. Electronic address: ruidsp@hotmail.com.
authors.forename: Rui Daniel
authors.initials: RD
authors.lastname: Prediger
authors.affiliation: Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil. Electronic address: tasca@ccb.ufsc.br.
authors.forename: Carla Inês
authors.initials: CI
authors.lastname: Tasca
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. Electronic address: eduardo.zimmer@ufrgs.br.
authors.forename: Eduardo R
authors.initials: ER
authors.lastname: Zimmer
authors.affiliation: Laboratorio de Biología Reproductiva y Evolución, Instituto de Diversidad y Ecología Animal - IDEA/CONICET, Universidad Nacional de Córdoba - UNC, Vélez Sarsfield 299, 5000 Córdoba, Argentina; Programa de Pós-Graduação em Biologia, Universidade do Vale do Rio dos Sinos - UNISINOS, São Leopoldo, RS, Brazil. Electronic address: luizernesto@gmail.com.
authors.forename: Luiz Ernesto
authors.initials: LE
authors.lastname: Costa-Schmidt
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. Electronic address: diogolosch@gmail.com.
authors.forename: Diogo Losch
authors.initials: DL
authors.lastname: de Oliveira
authors.affiliation: Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Universidade Federal de Santa Catarina, Campus Curitibanos, Curitibanos, SC, Brazil; Programa de Pós-Graduação em Ciências Fisiológicas, Centro de Ciências Biológica, Universidade Federal do Sergipe, São Cristóvão, SE, Brazil. Electronic address: giorgviola@gmail.com.
authors.forename: Giordano Gubert
authors.initials: GG
authors.lastname: Viola
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D004777:Environment; D005106:Exploratory Behavior / Q000502:physiology*; D006799:Housing, Animal; D008297:Male; D018782:Maze Learning / Q000502:physiology*; D051379:Mice; D009043:Motor Activity / Q000502:physiology*
keywords: Anxiety; Circadian rhythm; Cognition; Enriched environment; Exploration; Principal component analysis