International Journal of
Fisheries and Aquaculture

  • Abbreviation: Int. J. Fish. Aquac.
  • Language: English
  • ISSN: 2006-9839
  • DOI: 10.5897/IJFA
  • Start Year: 2010
  • Published Articles: 223

Full Length Research Paper

Growth and nutrient efficiency of meagre (Argyrosomus regius, Asso1801) fed extruded diets with different protein and lipid levels

Silvia Martínez-Llorens*, Javier Espert, Javier Moya, Miguel Jover Cerdá and Ana Tomás-Vidal
Institute of Animal Science and Technology, Group of Aquaculture and Biodiversity, Polytechnic University of Valencia, Camino de Vera, 14. 46071- Valencia, Spain.
Email: [email protected]

  •  Accepted: 26 May 2011
  •  Published: 31 October 2011

Abstract

 

Four commercial diets containing different levels of crude protein and crude lipid (44/25, 43/21, 46/20 and 47/20%) were assayed in duplicated groups in juvenile meagre (Argyrosomus regius) (initial individual weights were 94 g) in an experiment lasting 173 days. The essential amino acid contents (expressed in g/kg of diet basis) in diets 46/20 and 47/20 were higher than in diets 44/25 and 43/21. The HUFAs represented 184 and 207 g/kg in diets 46/20 and 47/20, respectively and 98 and 116 g/kg in diets 44/25 and 43/21, respectively. The fish fed diet 47/20 obtained the best growth and efficiency results, reaching a final individual weight of 393 g, followed by the meagre fed with diet 46/20. Meagre from the 47/20 group retained more of the ingested protein and energy than those  fed diets 46/20.  Fish fed 44/25 and 43/21 obtained the significantly lowest protein and energy efficiency. The retention of individual amino acids (AAs) in fish fed diets generally decreased in order of diets 46/20, 43/21 and 44/25. The IAA retention of meagre fed diet 47/20 was around 24.8% in phenylalanine and 39.7% in lysine. The results of the current experiment show that the fish fed commercial diet 47/20 obtained the best results in meagre growth, followed by fish fed diet 46/20. Diets 43/21 and 44/25 presented the worst growth and feed efficiency results.

 

Key words: Meagre, protein level, lipid level, extruded diets.