COMPOSITION AND METABOLIZING OF LIPIDS AND FATTY ACIDS IN MUSCLE OF FEMALE ANGUILLA JAPONICA DURING THE PERIOD OF ARTIFICIAL INDUCING OVARIAN MATURATION

This experiment adopted three methods(IGD,InGD and AnGD) to treat the females of Japanese eel.After being treated,the biological data of female,which related with their gonadal development,were investigated and the changes of fatty acids in their muscle were measured by gas liquid chromatography.The purpose of this study is try to discuss the lipid consumptions for gonadal development,basal metabolization and migration fuel during spawning migration,as well as the relationship between gonadal development and fatty acids consumption in the period of artificial inducing gonadal maturation,in order to provide referenced foundation for future studies on artificial propagation in Japanese eel.The results indicated that the body weight of females came through a course of gradual downward trend before the 10 injection and rapid rise at the beginning of spawning,which was called hydration,as well as the lipids of muscle tissue were necessary not only for gonadal development,but also for basal metabolization and migration energies in Japanese eels during the spawning migration.In this study,17 fatty acids were detected in muscle tissues of females,including 7 SFA,2 MUFA and 8 PUFA.Among them,there were only two kinds of MUFA,but their total levels were higher and reached at 38.02 percent of total lipids.Their consumptions were related with gonadal development and basal metabolization,unrelated to the energy for swimming.Among 8 PUFA,the changes of AA in three treated groups were very special.It was a dynamic course of accumulation and consumption in muscle tissue of Japanese eel during the period of experiment and the accumulation was related with the swimming of females.The more the females swam,the more AA was accumulated in muscle tissues.DHA levels of muscle tissues in Japanese eels were the highest,its change was remarkably different between treated groups and its level in control reached up to(123.91?.29) mg/g DMW,accounting for 32.52 percent of total lipids.However,its level in IGD group dropped at(10.59?.85) mg/g DMW at the end of experiment.Relativity analyses indicated that the relativities between GSI and the levels of total lipids,PUFA,DHA and EPA were all showed in some extent negative relativities,but the closest factor was DHA,r=-0.952(P0.01,n=5),the most distant one was EPA,r=-0.882(P0.05,n=5).Therefore,it was indicated that DHA was the most important fatty acid during the period of gonadal development in Japanese eel.Analyzing for energy distribution considered that the lipid consumption for basal metabolization(LBM) accounted for 34.68% of total lipids,gonadal development(LGD) accounted for 32.94% and swimming energy(LSE) accounted for 9.79%.After finished spawning,the muscle of females was also reserved 23.04% of total lipids.Therefore,it can be undoubted that Japanese eels not only can provide enough energy to finish the spawning migration so far as over 2000 sea miles but also make the gonadal normal development without intake any food.