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Experiments were conducted to study the effects of dietary lipids& astaxanthin supplemented diets on accumulations of ovaries & eggs, and hatched percent of eggs of Macrobrachium rosenbergii.
Results were:Prawns fed the soybean oil & squid viscera oil diets were found a higher fecundity than others. Percents of HSI & GSI,the content of lipids in the ovary, and hatched percent of eggs were highter in the group fed with squid viscera oil diet. Although there were promotionally increased the percent of GSI,more content of lipids & higher hatched percent of eggs in the group fed with lecithin diet, but the percent of incompletely molting death was the highest. The accumulation of lipids in the hepatopancreas started from the 2nd stage to the 3rd stage. And the accumulation of lipids in the ovary started from the 3rd stage. So,the ovary developed from the 3rd stage. Lipids of eggs decreased with embryonic development. The higher percent compos- ition of nonpolar lipid fraction was in the hepatopancreas, but more content of polar lipid fraction was in the ovary. The NPL/PL ratio was 7/3 in the egg. Total lipid & fatty acid composition in tissues were influenced upon the kinds of dietary lipids.
Contents of lipids in tissues & the hatched percent of eggs were not influenced upon the dietary astaxanthin. But accumulational contents of total carotenoids in eggs were influenced upon the supplemented levels of dietary astaxanthin. The carotenoid contents of eggs decreased with embryonic development. But the highest content was found at the 2nd stage. The results suggested supplemented from 3% to 4% of squid viscera oil in the diet was more effective in the ovarian development & egg hatchability. And at least supplemented 16.7 ppm of astaxanthin in the diet could decrease the degradation of pigmentation in the carapace.
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