| In this study, the effects of different temperatures on the embryonic development of Oxyeleotris
marmorata and morphological observation of post-embryonic development were examined. The results indicated that,
in a certain temperature range, with the water temperature rising, the speed of hatching was expedited. The optimum
temperature on embryonic development was 26.5-29.0益, with hatching rate of 86%, and mortality rate of newly
hatched larvae less than 15%. At 29益, the effective accumulated temperature was 1 185.7 益窑h in embryonic
development, and the threshold temperature was calculated as 13.8益. The post-embryonic development (mainly the
larvae stage) of O. marmorata could be divided into two periods (yolk sac larva and late larva) and eight stages,
including hatching larva stage, rudiment of pectoral fin stage, xanthic eye stage, melanoid eye stage, emergence of air
bladder stage, exhaustion of yolk stage, chordal tip lifting stage and formation of fin stage. The newly-hatched larva
was transparent, and the average length was 2.8-3.2 mm. Its nutrition was mainly raised by yolk. Once the mouth and
its digestive tract were fully developed, larva was able
to feed and turned into the mixed vegetation period.
120 -144 h after hatching, the larva depended on
exterior nutrition completely since yolk was exhausted.
Thereafter, coccygeal vertebra started to become
warped, to form the caudal fin, dorsal fin, anal fin and
pelvic fin, to present preliminary fish signs. |
