The present study was carried out in the Marine Fish Laboratory (MFL), Faculty of Agriculture Saba Basha, Alexandria University, Egypt to study the possibility of early weaning of gilthead seabream (Sparus aurata) larvae. Therefore seabream larvae divided into different groups and weaned at 25, 27, 29, 31, 33, 36 and 39 days post hatching (dph). At the end of the experiment the mean wet weight and length of gilthead seabream larvae after 45 dph showed that, the late weaning (33, 36 or 39 dph) significantly increased the wet weight and length of larvae compared to larvae groups that early weaned (25 and 27 dph) and the same trend was also observed for larvae after 60 dph.
Weight gain of gilthead seabream larvae during the period of 45-60 dph ranged between 0.039 to 0.052 gm. The early weaning significantly decreased larvae weight gain (groups 25, 27 and 29 dph) while the late weaning (36 and 39 dph) significantly improved weight gain and the same trend was also observed during the entire experimental period (30-60 dph ).
During the entire experimental period the average larvae specific growth rate found to be 1.39, 1.60, 1.59, 1.54, 1.65, 1.70 and 1.71 for larvae groups weaned at 25, 27, 29, 31, 33, 36 and 39 dph, respectively and the differences between these means were significant.
At 30 dph survival rates for seabream larvae groups found to be 78.67, 86.67, 88.00, 85.33, 88.00 and 88.00. At 60 dph the average survival rates found to be 88.00, 90.33, 89.00, 86.33, 92.00, 99.00 and 89.33% for larvae groups weaned at 25, 27, 29, 33, 36 and 39 dph, respectively and the differences between these averages were significant.
Protein and fat content of gilthead seabream larvae at the end of the experiment ranged between 31.20-36.20 for protein and 2.10 -3.36% for fat, respectively. The obtained results indicated that the late weaning (36 and 39 dph) significantly increased each of protein and fat content of larvae when compared to the early weaning (25 and 27 dph).
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