The compensatory growth response (CGR) and some selected physiological parameters
were evaluated in sobaity (Sparidentex hasta, 10 g) and yellowfin seabreams
(Acanthopagrus latus, 4.3 g) juveniles subjected to a 2-week
restricted feeding. Fish
were first fed at 0%, 25%, 50% and 75% of the satiation level for a 2-week
period, and
then, they were refed for 6 weeks at the visual satiation level. The control group was
fed to the satiation everyday for 8 weeks. Three hundred sobaty seabream juveniles
were stocked into 15 tanks (20 fish tank−1), and 450 yellowfin seabream juveniles were
allocated into 15 tanks (30 fish tank−1) and were fed on a commercial feed (500 g kg−1
crude protein and 150 g kg−1 crude fat). Survival rate was decreased in R0% group in
S. hasta because of the cannibalism, which was triggered by feed restriction. After
the 2 weeks of feed restriction, the control and R0% treatments in S. hasta (16.0 vs.
9.3 g) and A. latus ( 3.9 v s. 6 .2 g) h ad t he h ighest a nd l owest b ody w eight, r espectively.
After the 6 weeks of refeeding trial, all the ration-restricted
groups showed
a full CGR in S. hasta. Regarding A. latus juveniles, except for R0%, the other groups
showed a full CGR. Feed conversion ratio was improved in S. hasta that subjected to
the 2-week
feed restriction, but this parameter did not change in A. latus. Antioxidant
enzyme activities in the liver of S. hasta juveniles, including glutathione-S-
transferase,
glutathione peroxidase, superoxide dismutase and catalase along with liver enzymes
including alkaline aminotransferase, aspartate amino transferase, lactate dehydrogenase
and alkaline phosphatase gradually were decreased with reducing the severity
of the feed restriction. Regarding A. latus, all mentioned antioxidant and the liver enzymes
in the feed-restricted
groups were higher than the control. R75% and control
groups in S. hasta had the greatest and the least trypsin and alkaline phosphatase
activities. In A. latus, R25%, R50% and