Variations in
lipid classes and fatty acid content in tissues of wild Macrobrachium
rosenbergii (de Man) females during maturation
R.O. Cavalli, M. Tamtin,
P. Lavens, P. Sorgeloos-2001
Aquaculture, 193 (3-4): 311-324
Abstract:
This study describes the variations in total lipid,
lipid classes and fatty acids in the midgut gland (MG), ovary, and muscle
tissue of wild-caught Macrobrachium rosenbergii to elucidate the importance
of these components during sexual maturation. Mature females were captured
in the Mae Klong River, Thailand, from July to September 1998, and divided
into five groups according to their ovarian development. Total lipid levels
in the ovary increased with maturation, but no concomitant decrease in MG
lipids was observed. Thus, the lipid requirements of the developing ovary
are thought to be more dependent on the immediate ingestion of dietary lipid
than on MG reserves. Higher proportions of neutral lipids (NL), mainly
triacylglycerols (TG), were observed in both MG and ovary, whereas polar
lipids (PL) predominated in muscle. In the ovary, total NL increased
significantly along with maturation mainly due to an increase of TG and
sterols. Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) formed
the bulk of ovarian PL and also increased significantly as maturation
progressed. Major fatty acids in both MG and ovary were 14:0, 16:0, 18:0,
18:1n-9, 18:2n-6, 18:3n-3, 20:4n-6, 20:5n-3 and 22:6n-3. Significant
increases in the levels of saturated and mono-unsaturated fatty acids were
observed in both MG and ovary. The levels of n-3 highly unsaturated fatty
acids (HUFA), particularly 20:5n-3, decreased in the MG as ovarian
development proceeded. In contrast, an increase in the ovarian contents of
n-3 HUFA was detected.
(Laboratory of Aquaculture & Artemia Reference
Center, Ghent University, Rozier 44, 9000 Ghent, Belgium, e-mail of P.
Sorgeloos: patrick.sorgeloos@UGent.be)
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