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Abstract
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Dynamic changes of tissues, organs and growth that occur in fish larvae during the transition to the juvenile stage
are accompanied by differences in metabolic, locomotor and feeding activities that can reflect on fish's oxidative
status. In this study, we examine how body growth, antioxidant system (superoxide dismutase (SOD), catalase
(CAT), glutathione reductase (GR) and total antioxidant capacity (TAC) and oxidative damage (malondialdehyde-
MDA) parameters change in larvae of yellowfin seabream larvae (Acanthopagrus latus) during early
development (0, 7, 15, 22 and 30 day after hatching-DAH). Body growth (length and weight) starts to intensify
from 15 DAH. We observed general increase in the antioxidant system (AOS) with the age of larvae from newly
hatched and 7 DAH up to 15 and 22 DAH individuals. 15 and 22 DAH larvae had the greatest levels of TAC, SOD
and GR activity, while 30 DAH larvae had higher CAT activity from 0, 7 and 15 DAH and MDA concentration in
comparison to 15 DAH individuals. Several developmental events can be linked with observed results: lower AOS
in 0 and 7 DAH individuals with low locomotor activity, growth, endo-exogenous feeding phase and cell differentiation;
15 and 22 DAH larvae are under pressure of fast growth, enhanced swimming and foraging capacity;
while higher MDA production in 30 DAH larvae can be a result of shifts in muscle metabolism, changes in both
quality and quantity of food and a significant increase in weight. The present study provides insight into the
changes in redox status during the ontogeny of A. latus, fish species about which physiology is still little known
but with a potential for use in marine culture. Ability to lower oxidative stress during critical developmental
periods can enhance that potential.
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