الفهرس 
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Abstract
5. The present study was carried out in the Marine Fish Laboratory (MFL), Faculty of Agriculture Saba Bacha, Alexandria University, Egypt to study the possibility of early weaning of seabream larvae. Therefore seabream larvae, each with three replicated, were weaned at different ages ( 25, 27, 29, 31, 33, 36 and 39 days post hatching dph). Growth performance parameters (BW,BL,K,WG,SGR and SR) were measured or calculated through the experiment period (35 days).Protien and fat content of gilthead seabream larvae were determined at the end of experiment br - Results obtained could be summarized as follows : br - The average larvae wet body weight at the rearing day 30 -#102;-#114;-#111;-#109; hatchability was found to be 0.148, 0.147, 0.149, 0.152, 0.150, 0.150 and 0.150 g for larvae weaned after 25, 27, 29, 31, 33, 36 and 39 dph, respectively. The mean wet weight of gilthead seabream larvae after 45 dph showed that, the late weaning (33, 36 or 39 dph) significantly increased the wet weight of larvae compared to larvae groups that early weaned (25 and 27 dph) and the same trend was also observed for gilthead larvae after 60 dph. br - The average larvae body length at the rearing day 30 day post hatching (dph) ranged between 0.73 and 0.76 cm for the different larvae groups. Larvae group weaned at 36 dph showed the longest body length (0.76 cm) while the early weaned larvae (25 dph) showed the shortest one (0.73 cm). The average body length of gilthead seabream larvae day 45 dph was 0.96, 0.98, 1.09, 1.19, 1.11, 1.23 and 1.27 cm for larvae groups weaned at 25, 27, 29, 31, 33, 36 and 39 dph, respectively. At the rearing day 60 dph mean body larvae lengths were 1.38, 1.43, 1.45, 1.51, 1.61, 1.59 and 1.70 cm for larvae groups weaned at 25, 27, 29, 31, 33, 36 and 39 dph.Weaning age significantly affected gilthead seabream larvae body length. br - Condition factor values after 30 dph were ranged between 6.62 and 6.77 with insignificant differences between fish groups weand at 25, 27, 29, 31, 33, 36 and 39 dph. The average values of K at 45 dph were ranged between 5.27 – 6.42 and the differences between these means were significant and the same trend was aslo observed at 60 dph. br - The average WG for the experimental period -#102;-#114;-#111;-#109; 30 to 45 dph for the different larvae groups was found to be 0.036, 0.039, 0.040, 0.041, 0.046, 0.048 and 0.048 g for the larvae weaned at 25, 27, 29, 31, 33, 36 and 39 dph, respectively. Weight gain of gilthead seabream larvae during the period -#102;-#114;-#111;-#109; 45 to 60 dph was ranged between 0.039 and 0.052 g. The early weaning of larvae 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 ). br - During the entire experimental period the average larvae SGR was 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. Weaning age of gilthead seabream larvae significantly affected SGR. br - -#102;-#114;-#111;-#109; 25 to 45 days post hatching, survival rates for seabream larvae groups were 78.67, 84.00, 86.67, 88.00, 85.33, 88.00 and 88.00 for larvae groups weaned at 25, 27, 29, 31, 33, 36 and 39 day after hatching, respectively. The survival rate of the weaned larvae. -#102;-#114;-#111;-#109; 45 to 60 dph, the average survival rates were 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, 31, 33, 36 and 39 dph, respectively survival rates were significantly affected by the weaning age of larvae. br - Protein and fat contents of gilthead seabream larvae at the end of the experioment ranged between 31.20 and 36.20 for protein and 2.10 and 3.36% for fat. Results indicated that the late weaning of larvae (36 and 39 dph) significantly increased both protein and fat content of larvae when compared to the early weaning of larvae (25 and 27 dph). Weaning age of sebream larvae significantly affected protein and fat contents of gilthead seabream larvae. br It could be concluded that:- br -#102;-#114;-#111;-#109; the above results we concluded that the best weaning age is above 30 days post hatch due to high survivability, low mortality, increasing ability of the fry to eat for obtaining high body weight and increasing length and thus returns on economic efficiency of production system of seabream larvae specially the known protocol of weaning age of seabeam advices that the best time for weaning is after 60 days post hatch. br So, we advise that the study needs further work in future to confirm these results.