Preliminary results of providing various combinations of live foods to grouper (Epinephelus coioides) larvae

Fertilized oyster eggs, S-rotifer (Brachionusrotundiformis) and SS-rotifer (Brachionus sp.),were tested either solely or in combination fortheir suitability as feed for early stage grouper (Epinephelus coioides) larvae. Sizes ofS-rotifers ranged between 143-224 µm lorica lengthwith mean 182±21µm, and SS-rotifersbetween 122-176µmlorica length with mean 154±13µm. Theresults indicated that both fertilized oyster eggs andSS-rotifers were suitable as feed at F1 (first feedingday). However, poor growth was recorded when providing oyster eggs solely for the periodsF1-F3. Although growth of larvae at F6 had nodifference between the sole SS-rotifers and the oystereggs additionally provided for F1-F3, better survivalof larvae at F15 was obtained when providingcombinations of SS-rotifers with oyster eggs for F1-F3.Besides, better growth and survival of larvae at F15was found when providing S-rotifers enriched withKirin yeast for F7-F15. The highest survival andfastest growth of larvae at F15 was found whenproviding oyster eggs for F1-F3, SS-rotifers forF1-F6, S-rotifers for F7-F15, both rotifers enrichedwith Kirin yeast, and Isochrysis for F1-F15.Total fatty acid (TFA), EPA, DHA content, and DHA/EPA(D/E) ratio of larvae changed with their sizes andcorresponded to that of their feeds. The F15 larvaehaving a higher TFA grew faster, having higher DHA orEPA survived better.