Effect of Replacing Soybean Meal by Slaughterhouse Poultry By-Products Meal on Nutrient Digestibility Ecoefficiency and Accumulation of Elements of the Nile Tilapia (Oreochromis niloticus L.) under Aquaponics System Conditions

The present study was carried out to investigate the impact of substituting  soybean meal with slaughterhouse poultry by-products meal on the Nile tilapia composition, mineral content, apparent digestibility co-efficiency, and basil yield composition under aquaponics system conditions. In an 84-day feeding experiment and 30-day digestibility trial, three isonitrogenous and isocaloric diets (control, SPBM50%, and SPBM100%) were formulated to contain 30% CP. As result, neither the carcass content of moisture nor the CP was affected by the experimental diets. On the other hand, the fish fed SPBM^100% content showed high significant ash content, while those fed SPBM^50% content recorded high significant EE and GE contents. The differences were notably not significant among the different treatments. The fish group fed SPBM^50% diet recorded significantly higher concentrations of minerals than those fed control and SPBM^100% diets. The concentration of heavy metals in fish muscles was within the permissible limits for human health protection. The SPBM^50% treatment recorded the highest levels in DM, CP, EE and CF contents. No significant difference was observed in ADC of DM, CP, CF, NFE, and GE kcal/g (%) in fish fed the experimental diets. The ADC of EE content of diets was higher in the SPBM^100% diet that exhibited significant differences with the control treatment. In conclusion,  the SPBM^100% has a positive effect on basil composition under aquaponic system conditions as a good source of minerals that are more available, Moreover,  it has  no impact on the accumulation of heavy elements in fish muscles.