Evaluation of pollard substitution with water hyacinth Eichhornia crassipes on enzyme activity and growth performance of tilapia Oreochromis niloticus

Abstract

The present study was to subtitute pollard as one of raw materials in fish feed production obtained from the import with other raw material. One potential alternative raw material is water hyacinth Eichhornia crassipes. This research was conducted with 5 treatments and 3 replications namely feed with substitution of pollard with E. crassipes at 0%, 25%, 50%, 75% and 100%. On the test of growth performance, tilapias (Oreochromis niloticus) with the initial weight of 6.55 ± 0.02 g fish-1 were maintained for 60 days. On digestibility test, treatment feeds were added with 0.6% Cr2O3 and fed to tilapia with a weight of 23.70 ± 0.48 g fish-1. The results show that tilapia fed with 50% replacement rate of pollard yielded similar relative growth, feed efficiency, protein retention and protein digestibility with 0% treatment. The activities of protease, amylase and cellulase decreased due to the increase in water hyacinth in the feed. In conclusion, water hyacinth flour can be used up to 50% as a pollard substitution with 12.5% of material quantity in the diet of tilapia