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Abstract The present work is conducted to study effect of some feeding and rearing systems on productive performance of the Egyptian sole (Solea aegyptiaca) as a follows: The first part: Effect of sex ratio and stocking density on the induced spawning of Solea aegyptiaca. The second part: Effect of some feeding and rearing systems on growth and development of Solea aegyptiaca larvae. The third part: Effect of diet type and stocking density on growth performance and blood parameters of Solea aegyptiaca fingerlings. The first part: Broodstock spawners were intermuscularly injected with Human Chorionic Gonadotropin Hormone (HCG) below the dorsal fine base, the dose was 7000 IU/Kg body weight of fish. In this study, three different broodstock sex ratios: 1:1, 1:2 and 2:1 (male ♂: female ♀) were tested. Under the conditions tested in this study, larvae production of Solea aegyptiaca was affected by different broodstock sex ratios and improved at a sex ratio (1♂:2♀). Also, four different broodstock stocking densities: 0.5, 0.75, 1, 1.25 Kg/m3 were tested. Under the conditions tested in this study, larvae production of Solea aegyptiaca was affected by different broodstock stocking densities and the best stocking density was 0.75 Kg/m3. Also, results demonstrated superiority of artificial spawning compared to natural one. The second part: The first experiment was tested five different feeds type (live food (Rotifer and Artemia) and poultry egg (whole egg, egg white, egg yolk and boiled egg yolk)). The results indicated that, larvae that fed on live food showed statistically higher growth rate compared to all the other groups. Survival rate values were relatively high with fed on egg white and fed on live food. The second experiment was tested five different salinities (10, 15, 20, 25 and 30‰). The results found that, no significant difference in growth rate, but the best performance and survival rate of larvae was at salinity 20‰. The third experiment was tested eight different water temperature (16, 17, 18, 19, 20, 21, 22 and 23°C). The results showed that, the larvae under temperature 20 °C showed the highest growth rate, while the best survival rate was recorded at temperature 16 °C under experimental conditions. The fourth experiment was tested four different photoperiods (light, L: dark, D): 6L:18D, 12L:12D, 18L:6D and 24L:0D). The results indicated that, the best growth performance of larvae was at photoperiods 18L:6D and 24L:0D. Larvae exposed to photoperiods (12L:12D, 18L:6D and 24L:0D) led to relatively higher survival rate compared to 6L:18D. The fifth experiment was tested four different stocking densities (50, 80, 110 and 140 larvae/ liter). The results found that, no significant difference in growth performance. Stocking density of 110 larvae/liter led to relatively higher survival rate compared to the other stocking densities. The sixth experiment was tested three different feed (Artemia (T1), Artemia + artificial feed (T2) and artificial feed (T3)) of Solea aegyptiaca post-larvae weaning. Results of growth performance parameters were highest with postlarvae fed on (T1) compared to the other feeds (T2 and T3 ). Larvae fed on (T1 and T2 ) led to higher survival rate compared to fed on (T3). |