Dietary Value for Larval Swimming Crab Portunus trituberculatus of Marine Rotifer Brachionus rotundiformis Cultured with Several Feeds.

Larvae of swimming crab were reared in 1-2 l tanks, supplied with marine rotifers cultured with several feeds: baker's yeast, baker's yeast fortified with cuttlefish liver oil, freshwater Chlorella, and marine micro algae Nannochloropsis. The fatty acid compositions of the rotifers were analyzed to evaluate their dietary value. Larval survival, growth and velocity of development were improved according to the amount of n-3 highly unsaturated fatty acids (n-3HUFA) contained in rotifers. Consequently, it was considered that the larval swimming crab demanded the n-3HUFA in feeds as essential fatty acid and enrichment of feed rotifers should be a routine technique in the seed production process of the swimming crab.