title: Daily feeding and protein metabolism rhythms in Senegalese sole post-larvae.
abstract: Fish hatcheries must adapt larval feeding protocols to feeding behavior and metabolism patterns to obtain more efficient feed utilization. Fish larvae exhibit daily ingesting rhythms rather than ingesting food continuously throughout the day. The aim of this study was to determine the daily patterns of feed intake, protein digestibility, protein retention and catabolism in Senegalese sole post-larvae (Solea senegalensis; 33 days post-hatching) using14C-labeled Artemia protein and incubation in metabolic chambers. Sole post-larvae were fed at 09:00, 15:00, 21:00, 03:00 and 09:00+1 day; and those fed at 09:00, 21:00, 03:00 and 09:00+1 day showed significantly higher feed intake than post-larvae fed at 15:00 h (P=0.000). Digestibility and evacuation rate of ingested protein did not change during the whole cycle (P=0.114); however, post-larvae fed at 21:00 and 03:00 h showed the significantly highest protein retention efficiency and lowest catabolism (P=0.002). Therefore, results confirm the existence of daily rhythmicity in feeding activity and in the utilization of the ingested nutrients in Senegalese sole post-larvae.
authors.affiliation: Instituto de Ciencias Marinas de Andalucía (ICMAN-CSIC), Apartado Oficial, Cádiz, Puerto Real 11519, Spain carmen.navarro@icman.csic.es.
authors.forename: Carmen
authors.identifier: http://orcid.org/0000-0001-5490-0328
authors.initials: C
authors.lastname: Navarro-Guillén
authors.affiliation: Instituto de Ciencias Marinas de Andalucía (ICMAN-CSIC), Apartado Oficial, Cádiz, Puerto Real 11519, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Yúfera
authors.affiliation: Centro de Ciências do Mar (CCMAR), Edifício 7, Universidade do Algarve, Campus de Gambelas, Faro 8005-139, Portugal.
authors.forename: Sofia
authors.initials: S
authors.lastname: Engrola
keywords: Daily feeding pattern; Feed intake; Post-larvae; Protein metabolism; Solea senegalensis