Cultured copepods as food for West Australian dhufish (Glaucosoma hebraicum) and pink snapper (Pagrus auratus) larvae

Copepods have often improved larvicurture of marine fish species that are n ot easily reared using rotifers. One such species is Glaucosoma hebraicum. G. hebraicum larvae were reared on a combined diet consisting of equal numb ers of cultured copepod nauplii and rotifers and a diet of rotifers only. G rowth was significantly greater in larvae fed with the combined diet. Survi val was 37% in the copepod/rotifer-fed larvae compared to 5% in the rotifer -fed larvae. Two separate methods of presenting copepod nauplii to Pagrus a uratus larvae were also examined. Firstly, copepods nauplii were provided a s the sole diet during the first feeding phase followed by rotifers. Second ly, rotifers were supplemented with copepod nauplii for an extended period. P. auratus larvae grew faster than rotifer fed controls in both trials. La rvae fed with the supplemented diet for an extended period grew fastest. Th ere was no significant difference in survival and swim bladder inflation in P. auratus larvae, although those treatments with copepods in their diet w ere consistently higher. Improved larval growth and survival in both fish s pecies were attributed to preferential selection of copepod nauplii and the ir high nutritional content. (C) 2001 Elsevier Science B.V. All rights rese rved.