World Aquaculture Society Meetings

GROWTH AND BEHAVIOR OF LARVAL ZEBRAFISH Danio rerio FED A PROCESSED DIET, LIVE FOOD, OR THE COMBINATION    

Joan M. Hedge*, David Korest, Deborah Hunter, and Stephanie Padilla
 
 Integrated Systems Toxicology Division,
NHEERL, US EPA,
Research Triangle Park, NC 27709

Because Zebrafish (Danio rerio) have become a popular and important model for scientific research, the capability to rear larval zebrafish to adulthood is of great importance.  Recently research examining the effects of diet (live versus processed) have been published.  In the current study we examined whether the larvae can be reared on a processed diet alone, live food alone, or the combination while maintaining normal locomotor behavior, and acceptable survival, length and weight at 14 dpf in a static system.

A 14 day feeding trial was conducted in glass crystallizing dishes containing 500 ml of 4 ppt Instant Ocean.  On day 0 pdf 450 embryos were selected as potential study subjects and placed in a 26C incubator on a 14:10 (light:dark) light cycle.  At 4 dpf 120 normally developing embryos were selected per treatment and divided into 3 bowls of 40 embryos (for an n=3 per treatment; 9 bowls total).  Treatment groups were: G (Gemma Micro 75 only), R (L-type marine rotifers (Brachionus plicatilis) only) or B (Gemma and rotifers). Growth (length), survival, water quality and rotifer density were monitored on days 5-14.  On day 14, weight of larva in each bowl was measured and 8 larva per bowl were selected for use in locomotor testing.  This behavior paradigm tests individual larval zebrafish under both light and dark conditions in a 24-well plate.

After 14 dpf, survival among the groups was not different (92-98%).  By days 7 -14 R and B larvae were ~2X longer than G larvae and on day 14 R larvae were slightly longer than B (Figure 1).  Weight per larva on day 14 was greater for the R group than either the G or B groups (Figure 2).  When normalized for length, locomotor behavior showed no differences in distance moved in either light or dark periods.  These results indicate that live diets may optimize growth of larval zebrafish during the first 14 days.  This abstract does not necessarily reflect U.S. EPA policy.




Copyright © 2001-2019 World Aquaculture Society All Rights Reserved.