Spawning and season affect
lipid content and fatty acid composition of ovary and liver in Japanese
catfish (Silurus asotus)
Nobuya Shirai, Hiramitsu Suzuki, Shigeru Toukairin,
Shun Wada-2001
Comparative Biochemistry and Physiology -- Part B: Biochemistry and Molecular Biology, 129(1): 185-195
Abstract:
The influences of spawning and season on lipid
content, lipid classes, and fatty acid composition were assessed in ovary
and liver of wild and cultured Japanese catfish (Silurus asotus). The
lipid content (7.3±1.6 g/100 g wet wt.) of ovary from wild catfish at
spawning was higher than that at post-spawn. However, no influence of
spawning on the lipid content of liver was observed. Docosahexaenoic acid
[DHA, C22:6(n-3)] in ovary lipids was 12.3±0.5% of total fatty
acids. The percentage of n-7 monounsaturated fatty acids in
triacylglycerol from the ovary and liver in the spawning season was high.
Percentages of C22:6(n-3) in phosphatidylcholine and
phosphatidylethanolamine from ovary were higher during spawning than after
spawning. No significant differences were observed in the lipid content of
ovary and liver from cultured catfish between seasons (summer vs. winter).
Content of arachidonic acid (C20:4n-6) in ovary and liver from
cultured catfish was higher in summer than in winter. There were differences
in lipid classes of ovary and liver by spawning and season. These results
suggest that the lipid metabolism in Japanese catfish is greatly influenced
by spawning and season.
(Department of Food Science and Technology, Tokyo
University of Fisheries, Konan, Minato, Tokyo 108-8477, Japan, Tel.:
+81-298-38-8089; fax: +81-298-38-7996, e-mail: nshinya@nfri.affrc.go.jp)