PROTEIN SYNTHESIS OVER 24 HOURS
IN JUVENILE BARRAMUNDI, Lates calcarifer AT DIFFERENT TEMPERATURES
R.S. Katersky, C.G. Carter
Temperature is recognized to be
the most important environmental factor affecting growth and
protein synthesis in fish. The optimal temperature for growth of juvenile
barramundi is 27°C, although culture often occurs at temperatures which
are above and below this optimum.
Juveniles (11.10 +/- 3.72 g) were
held at three different temperatures 21, 27 and 33°C and fed once
a day (504.5g kg-1
crude protein, 156 g kg -1 lipid,
128.5 g kg -1 ash, 20.1
GE MJ kg-').
Protein synthesis was measured at
0, 4, 8, 12 and 24 hours after feeding to determine when the
peak of protein synthesis occurred in white muscle, liver and whole body. At
the optimal temperature white muscle protein synthesis rates peaked
between 4 and 8 hours after feeding, however protein synthesis
remained significantly elevated over the initial 12 hours after feeding
when compared to rates at 24 hours. Understanding how different temperatures
affect the protein synthesis rates of juvenile fish will provide a better
understanding of processes that optimize growth efficiency.
(University of
Tasmania, Tasmanian Aquaculture and Fisheries Institute, School of
Aquaculture, Locked Bag 1-370, Launceston, Tasmania, Australia 7250, e-mail:
robink@utas.edu.au)