Fruit wastes improved the growth and health of hybrid red tilapia Oreochromis sp. and Malaysian mahseer, Tor tambroides (Bleeker, 1854)

Feeding trials were conducted to determine the effects of selected fruit wastes on hybrid red tilapia (Oreochromis sp.) and Malaysian mahseer (Tor tambroides). Seven experimental diets were formulated and produced using fruit wastes from pineapple skin (PS), pineapple crown (PC), jackfruit skin (JS), jackfruit pulp (JP), grated coconut (GC), mixed fruit wastes (JP + GC), and the control (CN). Triplicate groups of juvenile red tilapia (4.22 ± 0.05 g) and mahseer (2.31 ± 0.05 g) were fed twice daily to satiation for 60 days per trial. All fish fed with fruit-waste diets showed significantly (p < 0.05) better growth, survival rates, and health conditions than the control. The highest final weight gains were observed in tilapia fed with JP (16.68 ± 0.02 g) and GC (15.51 ± 0.12 g), which were significantly higher (p < 0.05) than the control (13.80 ± 0.05 g). The survival rates of tilapia were higher in GC, PS and JP (96.0 – 96.7%) compared to other treatments (< 93.0%). In mahseer, body weight gains in the mixed diet, JP + GC (7.70 ± 0.17 g), and JP (6.87 ± 0.08 g) were significantly higher (p < 0.05) than in the control (6.07 ± 0.11 g). The feed conversion ratio (FCR) in mahseer was significantly lower (p < 0.05) in fruit-waste diets compared to the control. The whole-body lipid for both fish was significantly higher (p < 0.05) in GC, JP and the mixed JP+GC fed diets compared with other treatments. After the challenge with Aeromonas hydrophila. the survival rates of both tilapia and mahseer fed with fruit-waste diets were significantly higher (p < 0.05) compared to the control. This study illustrated that dietary supplementation with fruit wastes could promote growth performance and stimulate the immune response against disease-causing agents.