Egg quality criteria in common dentex (Dentex dentex )

Centro de Acuicultura-IRTA, Ctra. Poble Nou Km 6, 43540 Sant Carles de la Rápita, Tarragona, Spain; Insitute for Zoology, University of Salzburg, Hellbrunnerstrasse 34, A-5020, Salzburg, Austria; Laboratory of Nutrition, Institute of Aquaculture, University of Stirling, Stirling FK9 4LA, Scotland, UK; Departamento de Biología Funcional. Laboratorio de Genética Acuícola, Facultad de Medicina, IUBA. Universidad de Oviedo, Julián Clavería s/n, 33071 Oviedo, Spain
Aquaculture (Impact Factor: 2.01). 01/2006; 260:232-243. DOI: 10.1016/j.aquaculture.2006.06.028
Source: OAI

ABSTRACT The spawning quality, in terms of hatching rate, larval mortality at 3 and 5 days post-hatching (dph) and day of total mortality of two
broodstock groups of common dentex was evaluated for 1 month in 2005. Several biochemical parameters including total lipid content,
lipid class and fatty acid composition, carbohydrate content and metabolic enzyme activities were analysed in all the egg batches
collected. Comparison was carried out between low- (mortality at 3 dph higher than 35%) and high-quality (mortality at 3 dph lower than
10%) batches. No differences were observed in lipid content and/or lipid class and fatty acid composition although a slightly higher
content of neutral lipids was detected in high-quality batches. However, significant differences were obtained regarding carbohydrate
composition and the activity of enzymes such as alkaline phosphatase and pyruvate kinase being higher in low-quality egg batches.

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