Dinâmica do perfil de ácidos graxos e composição de lipídeos em músculo de reprodutores, ovócitos e larvas das espécies Brycon orthotaenia (Günther, 1864) e Prochilodus argenteus (Spix & Agassiz, 1829)

Abstract

The aim of this work was to determine the dynamics of the fatty acid profile and the lipid composition in muscles of females, oocytes, newly-hatched larvae (NHL) and first-feeding larvae (FFL) of Brycon orthotaenia and Prochilodus argenteus. In B. orthotaenia, the total lipid remained constant in oocytes and larvae at different stages of development. The polar lipid (PL) concentration was abundant in oocytes and NHL, whereas for neutral lipid (NL) were higher in muscle and smaller in oocytes and NHL. In neutral lipid (NL), lower percentages of C18:2n 6, higher of C20:4n 6 (AA arachidonic acid) and C22:6n 3 (DHA docosahexaenoic acid) were found in FFL (P<0.05). Female muscles had the highest percentage of monounsaturated fatty acid ( MUFA). In the larval stages the percentage of polyunsaturated fatty acid sum ( PUFA) was higher (P<0.05). However in PL, the C18:3n 3, DHA and AA were higher in the larval stages and EPA was non-significant (P>0.05). The SFA was higher (P<0.05) in oocytes and lower in FFL. In P. argenteus, the highest percentage of total lipid was found in oocytes and NHL. NL and PL remained constant in oocytes and larval stages (P<0.05). NL had a higher percentage of C18:2n 6 in the muscle (P<0.05) and C18:3n 3 in the muscle and oocytes. Higher percentages of AA were found in muscle and in FFL (P<0.05). DHA presented higher values in NHL and FFL. In NL, SFA was higher in oocytes and during embryonic development (P<0.05). In MUFA, higher percentages were found in muscle, oocytes and NHL. PUFA presented higher percentages in muscle and FFL (P<0.05). However in PL, C18:2n 6 and AA had higher percentages in muscle (P<0.05) and EPA was higher in muscle and oocytes. Considering PL, SFA was higher in NHL and lower in FFL and in the muscle. MUFA presented higher percentages in oocytes and during the embryonic development (P<0.05). In both species the evidence that n-3 fatty acids were incorporated into the yolk from dietary source provided during vitellogenesis or from body reserves of the reproducers that were prepared to the oocytes. The increase of DHA reflects the potential of bioconversion of fatty acids obtaining n-3HUFA from C18:3n 3, demonstrating the importance of this for both species during larval development.