Performance of Larval Florida Pompano Fed Nauplii of the Calanoid Copepod Pseudodiaptomus pelagicus

Abstract

The Florida pompano Trachinotus carolinus is a highly prized marine fish species, the larviculture of which currently includes the feeding of live rotifers and nauplii of brine shrimp Artemia spp. However, no previous studies have evaluated the feeding of copepod nauplii. In this study, the growth and survival of Florida pompano larvae fed nauplii of the calanoid copepod Pseudodiaptomus pelagicus were compared with those of larvae fed the standard reference diet of enriched rotifers Brachionus plicatilis. Experiments were conducted during the first 7–9 d posthatch (DPH), a period preceding the provision of Artemia nauplii. Treatments included feeding only copepod nauplii during the first day, the first three days, and on all days, as well as copepod nauplii mixed with rotifers during the entire experiment. In addition, the dietary effects on larval fatty acid composition were examined. Feeding copepod nauplii at a density of 2.0–3.5 nauplii/mL during the first day or the first three days of feeding had advantages over feeding only rotifers. However, after approximately 3 DPH, increased quantities of nauplii were needed to provide sufficient nutrients for growth. This was demonstrated in larvae fed copepod nauplii for the entire trial, for which survival was significantly higher than for the other treatments but for which growth was significantly reduced. Larvae fed a mixture of rotifers and nauplii for the entire trial had survival similar to that of larvae fed only rotifers (∼40%); however, growth was greater in larvae fed the mixed diet, suggesting that there is a nutritional advantage to including copepods in the diet. Fatty acid analyses revealed that increased levels of docosahexaenoic acid were associated with larvae fed copepods, which probably contributed to the observed higher survival and growth. These results indicate that there are multiple benefits to feeding copepods to Florida pompano larvae.

Received June 6, 2010; accepted August 10, 2010

ACKNOWLEDGMENTS

We thank the Florida Department of Agriculture and Consumer Services Division of Aquaculture for funding this research. We thank Erik Stenn of AlgaGen, LLC of Vero Beach, Florida, for providing stock cultures of copepods and microalgae and for sharing culture expertise. We also thank Meghan Anderson, Fernando Cavalin, Kelly Chang, Shawn DeSantis, Matthew DiMaggio, Bryan Garr, Scott Grabe, John Marcellus, Amber Thomas, and Peter Woodward for assisting with various aspects of these experiments.

Notes

In this notation, the number to the left of the colon is the number of carbon atoms in the compound, the number immediately to the right of the colon is the number of double bonds, and the number after the hyphen indicates the position of the first double bond from the methyl end.