Nutritional studies in the seed production of fish-XII. Improvement of dietary value of brine shrimp Artemia salina for fish larvae by feeding them on .OMEGA.3 highly unsaturated fatty acids.

Abstract

Experiments were conducted in order to improve the dietary value for marine fish juveniles of Artemia naupii of the freshwater type, high in 18: 3ω3, by allowing them to feed directly on ω3 HUFA. In this method lipids containing ω3 HUFA were given directly to Artemia nauplii by homogenizing lipid with a small amount of raw egg yolk and water, together with baker's yeast; an emulsion resulted. The dietary value of the nauplii for juveniles of flunder, rock sea bream and red sea bream was compared for fish fed on various kinds of emulsified lipids or on baker's yeast. The newly-hatched nauplii were found to take up lipids very easily by this method. Feeding on the newly-hatched nauplii of the freshwater type or on those fed respectively baker's yeast and corn oil resulted in low growth and survival in all fish species used and in addition the rate of be effectively improved by feeding them lipids containing high amounts of ω3 HUFA such as cuttlefish liver oil, demonstrating that the class of EFA contained in Ariemia is the principal factor in the food value of Artemia nauplii to fish. Artemia eggs and nauplii from different locations (California, Brazil, Australia and China), were also analyzed for fatty acids in order to compare their food values to fish.