The aim of this study was to investigate the potential effects of incorporating Carica papaya leaf extract into practical diets for red hybrid tilapia to enhance growth and optimize feed utilization. Five diets were formulated with similar protein (35 %) and lipid (8 %) levels. While the compositions of raw materials in all diets were similar, they varied in papaya leaf extract (0.0 , 0.5, 1.0, 2.0, and 4.0%) inclusion . The diets were fed to triplicate groups of the fish (mean initial weight, 2.30 ± 0.01 g ) for twelve weeks.
Results showed that fish fed diet containing 2% papaya leaf extract (PLE) had the highest final weight of 31.14 ± 1.47 g, followed by those fed diet containing 1% PLE (27.27 ± 1.75 g). These two diets (1% and 2% PLE) had significant enhancements in weight gain, specific growth rate (SGR), and feed efficiency compared to the control group (p < 0.05 ). The inclusion of papaya leaf extract did not have a significant impact on hepato-somatic index (HSI), viscero-somatic index (VSI), protein efficiency ratio (PER), activity of digestive enzymes, blood composition, or survival rate of the fish (p > 0.05). Notably, supplementation with papaya leaf extract led to a reduction in serum urea levels.
The findings of this study suggest that incorporating papaya leaf extract into red hybrid tilapia diets can improve growth and feed efficiency without adverse effects on hematological parameters. Therefore, it is recommended to include papaya leaf extract at a level between 1% and 2% as a feed additive to enhance the growth of red hybrid tilapia fingerlings.