Nutritional Quality of the Wild Zooplankton as a Living Feed for Fish Larvae

Abstract

Several nutritive components of zooplankton collected at Maizuru Bay in October, 1982, and from May to August, 1983, were analyzed in order to clarify their food value to fish.
There was no remarkable difference in the proximate compositions among the wild zooplankton collected in October, May, June, July and August. The crude protein content of the wild zooplankton was higher than that of nauplii of Artemia salina. The content of vitamin B₆ was higher in the zooplankton of June than those of July and August. It was found that the content of viamin B₆ in wild zooplankton was higher thanthat of Artemia salina nauplii. Furthermore, pyridoxine was detected in the wild zooplankton, but not detected in Anemia salina nauplii.
Lipids of the wild zooplankton were rich in eicosapentaenoic acid and docosahexaenoic acid. Seasonal variation of fatty acid composition of the total lipid did not find markedly in the wild zooplankton.
Wild zooplankton was found to be high in the contents of ascorbic acid and ascorbic acid 2-sulfate. However, the content of total ascorbic acid and the ratio of ascorbicacid 2-sulfate were lower than those of Anemia salina nauplii.