Effects of fava bean (Vicia faba) on growth and muscle quality of red tilapia (Oreochromis sp.) cultured in hapa.

Abstract

This study was conducted to determine the replacement of fava bean (Vicia faba) for pellet feed in practical diets of red tilapia (Oreochromis mossambicus x Oreochromis niloticus) in the recirculating aquaculture system (RAS) and effect of fava bean on biochemical compositions of red tilapia included protein, lipid content and texture of meat. A completely randomized experimental design was developed with four treatments and three replicates. One thousand and two hundred red tilapia with average initial weight of 99.9±6.26 g were assigned to experimental hapas during ninety days. Fish in test treatments were completely feed by fava bean in 90 (FB90), 75 (FB75) and 60 (FB60) days, respectively, while the pellet feed was utilized in the control treatment (FB0). Based on results, the poorest growth performance and were observed in FB90 (278.01±82.28g) and FB75 treatment (284.94±62.61g) while the highest fish final weight (407±77.11g) was seen in FB0. Feed conversion ratio (FCR) in fish fed by fava bean within 90 days and 75 days were significantly higher (p<0.05) than those fed in 60 days. Similarly, fish body length was the highest in the control treatment. Fish survival rates were significantly different among treatments, being the highest 99.3% in FB0 compared to 91.3% in FB90. Protein content of fish was fed with fava bean for 90 days higher than 1.15 times, but lipid content was lower than 43.9% compared to fish was fed with aqua-feed diet. Hardness of “crispy” fish (117g.cm) significantly higher than control treatment (59g.cm). Although both growth rate and survival rate of “crispy” red tilapia was significantly lower than ordinary red tilapia, but flesh quality was dramatically improved.