Strawberry Calyx and its Impact on Fish Production Performance

Background and Objective: The plant wastes (inedible parts) contain many functional and nutraceutical compounds and are a rich source of bioactive components and fiber. These by-products have a bad effect on the environment. This study was conducted to evaluate the nutritional value of Strawberry Calyces (SC) when added as an additive to the tilapia diet and to investigate its effect on growth performance, feed utilization and the physiological status of fish. Materials and Methods: A 70 days nutritional experiment was done on four groups of tilapia fry with an initial weight of 1.53±0.02 g, which were fed on test diets (40.03% protein, 399.61 kcal) as control (0%), SC₁ (1%), SC₂ (2%) and SC₃ (3%) of strawberry calyces. Results: The results cleared those strawberry byproducts, rich in nutritional values  with a high percentage of dry matter which consists of main components such as phenolics, vitamins, minerals and considerable amounts of fatty and amino acids, that are promising when used as feed additives. Growth performance (weight gain, specific growth rate and length gain) was improved by increasing the level of additive up to 3%, compared to control. Also, feed utilization and body composition were enhanced for the fish. At the same trend, the immune response (IgM and IgD) was improved for the three examined fish groups especially cleared in those fed SC₂ and SC₃. Conclusion: This article hopes to be applied to the other plant residues and extend such studies to the use of many different plant residues that pollute the environment if left and study the impact of their use in feeding aquatic animals at various levels.