Five experimental diets were formulated and soybean meal protein in the basal diets was replaced by sunflower meal protein at an increased levels 25, 50, 75 or 100%. Therefore, five experimental diets were prepared and tested in the experiment in ten glass aquaria (two replicates for each treatment). The experimental period lasted after 90 days.
The highest average body weight (16.76 g) was recorded in group 1 which was fed on basal diet followed in a descending order by those fed the diet D3 (15.25 g), D2 (14.89 g), D4 (14.73 g) and D5 (12.62 g), respectively and the differences between these means were significant indicating the possibility of partial replacement of soybean meal by sunflower meal up to 75% without adverse effect on final body weight of Nile tilapia and similar trend was also observed for body length (BL), weight gain (WG), specific growth rate (SGR).
The feed conversion ratio (FCR) at the end of the experimental period were ranged from 2.44 for fish fed the basal diet (D1) to 4.05 for fish fed the diet D5(complete replacement of soybean meal) and the same trend was also observed for protein efficiency ratio (PER) and the differences in FCR and PER for the different treatment were significant.
The complete substitution of soybean by sunflower meal showed the highest protein content of whole fish followed in a descending order by those fed the diets D1, D4, D3 and D2, and the differences were significant (P |
