The present study consisted of two trials that conducted to evaluate the feeding frequency and the feeding time on growth performance, feed efficiency and body composition of rabbitfish Siganus rivulatus, the fish fed on one diet (35% crude protein). The first trial was conducted on rabbitfish fry (initial weight 0.18 g ± 0.012) and consisted of different three treatments of feeding frequency, the first treatment the daily meal divided into two times, the second treatment the daily meal divided into three times and the third treatment, the meal was divided into four times. The second trial was conducted on rabbitfish juvenile (initial weight 0.948 g ± 0.124) and consisted of different four treatments of feeding time. fish fed in two times the first treatment fed at 9am and 11am, the second treatment fish fed at 11am and 1pm, the third treatment fish fed 1pm and 4pm and the fourth treatment fish fed at 9am and 4pm. The statistical analysis of results indicated that, feeding frequency feeding time appeared significantly differences between the treatments in growth performance and feed utilization parameters. The total gain in weight and feed conversion ratio were affected by feeding frequency and feeding time. The results affirmed that, the third treatment (four time feeding /day) in the first trial and both the first and second treatments in the second trial were the best of the growth performance and feed utilization parameters.

No abstract

This study was conducted to determine the optimum feeding rate and evaluate the total replacement of fish oil as main source of fat by linseed oil from diet on growth performance and feed utilization of rabbitfish fry. This trial was factorial (3x2) and continued for 114 days. The average initial weight (W1) of fry was 0.18±0.012 g and the average initial length (L2) was 2.76 cm±0.05. This trial tested two factors, the feeding rate (5%, 7% and 9% of fish body weight) with two diets (36.44% CP) differed in oil source (diet A contained fish oil) and (diet B contained linseed oil). The stocking density was 40 fish per m3; fry was fed twice daily at 9 am and 4 pm. The results cleared that, insignificant differences between the different of feeding rates which used in this trial regardless the diet oil source, on the other hand, the growth parameters values increased with increasing the feeding rate and the diet which contained fish oil was the best in the growth parameters compared with the other which contained linseed oil. The growth performance parameters were significantly affected by interaction between feeding rate and oil diet source. Whereas, the fish fed at the diet (A) with 9% feeding rate was obtained the highest final weight (W2), Total Gain (TG), Relative Growth Rate (RGR), and Specific Growth Rate (SGR) in all the treatments. The feed utilization parameters were significantly affected by the feeding rates regardless of diet oil source. The best Feed Conversion Ratio (FCR) was recorded by the fish fed at 5% feeding rate, the statistical analysis did not show any significant differences between the fish fed at the diet (A) and diet (B) in all the feed utilization parameters. Also, the interaction between feeding rate and diet oil source on feed utilization of rabbitfish fry appeared significant differences in all the treatments. The best FCR value was achieved with was fish fed on the diet (B) and (A) at feeding rate 5%. Citation: Mohammed RA, Abdel-Aziz MFA, Abou-Zied RM, Allam SM (2017) Effect of Feeding Rate and Diet Oil Source on Growth Performance and Feed Utilization of Rabbitfish (Siganus rivulatus) Fry. J Fish Aqua Dev: JFAD-123. Citation: Mohammed RA, Abdel-Aziz MFA, Abou-Zied RM, Allam SM (2017) Effect of Feeding Rate and Diet Oil Source on Growth Performance and Feed Utilization of Rabbitfish (Siganus rivulatus) Fry. J Fish Aqua Dev: JFAD-123.

This study was conducted to evaluate the impact of sex ratio and stocking density on the induced spawning and reproductive performance of the Egyptian sole (Solea aegyptiaca) broodstock. 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. The highest fertilized eggs/ treatment and larvae/ treatment were observed in sex ratio (1♂:2♀). While, the highest fertilized eggs/ female, fertilized eggs/ g female, hatching rate and number of spawning were observed in sex ratio (2♂:1♀). Under the conditions tested in this study, larvae production of S. 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/m 3 were tested. The highest fertilized eggs/ treatment, fertilized eggs/ g female and larvae/ treatment were observed in stocking density 0.75 Kg/m 3 followed the other stocking densities. The lowest fertilized eggs/ female and/ g female were observed in stocking density 1.25 Kg/m 3. Under the conditions tested in this study, larvae production of S. aegyptiaca was affected by different broodstock stocking densities and the best stocking density was 0.75 Kg/m 3. Also, results demonstrated superiority of artificial spawning compared to natural one. From the results of this study, it is recommended to use artificial spawning in S. aegyptiaca with sex ratio (1♂:2♀) and stocking density (0.75 Kg/m 3).

This study was conducted to evaluate the optimum salinity and temperature on growth and development of Solea aegyptiaca larvae and weaning feed type on growth of Solea aegyptiaca post-larvae. The first 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 second 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 growth rate for larvae has been increased gradually with increasing temperature until 20 °C then decreased, while survival rate was decreased gradually with increasing temperature. The third experiment was tested three different feed (Artemia (T 1 ), Artemia + artificial feed (T 2 ) and artificial feed (T 3 )) of Solea aegyptiaca post-larvae weaning. Results of growth performance parameters were highest with post-larvae fed on (T 1 ) compared to the other feeds (T 2 and T 3 ). Larvae fed on (T 1 and T 2 ) led to higher survival rate compared to fed on (T 3 ).