Growth performance and hematological responses of silver barb (Barbonymus gonionotus bleeker, 1850) fingerlings to dietary blanched moringa (Moringa oleifera lam.) leaf meal as a substitute of soybean meal

The fastest-growing aquaculture industry relies heavily on animal protein, fishmeal and plant protein to maintain production levels. Therefore, present study was conducted to perceive the effectiveness of blanched moringa (Moringa oliefera) leaf meal (MLM) as a replacement of soybean meal in silver barb (Barbonymus gonionotus) fingerling diet. Four experimental feeds were prepared replacing soybean meal with MLM at 0, 10, 30, and 50%. Fish were reared for 60 days in 12 hapas installed in three similar size and shaped ponds comprising four treatments each having 3 replications. Fish were fed with the experimental diet at 5% body weight twice daily. Fish growth parameters and length-weight relationship were assessed. To determine their resistance to stressful conditions, the fish were submerged in low pH-5 solution at the conclusion of the experiment. According to the results of the fish growth metrics, the majority of the parameters were comparable and statistically insignificant between the treatments. However, when compared to the control, T(1) and T(2) treatments, the T(3) treatment demonstrated increased survival, PER, and fish production. In addition, other parameters such as percent weight gain, SGR, FCR and FCE were higher in control but statistically similar with T(3). Besides, the length-weight relationship of silver barb fingerlings fed with all the test diets showed a positive association and isometric growth pattern. With the incremental addition of MLM to the fish diet, the hematological parameters—red blood cells (RBC), white blood cells (WBC), hemoglobin (Hb), and mean corpuscular hemoglobin (MCH) gradually increased. The fish fed the T(3) diet had the highest recorded stress tolerance (6.50 ± 0.50 min), whereas the fish on the control diet had the lowest (T(0), 4.77 ± 0.68 min). According to the study, MLM has the potential to replace soybean meal in the diet of silver barb fingerlings to the tune of 50:50 without having an adverse impact on growth. It can enhance fish hematological performance and tolerance for unfavorable environmental conditions as well.