Evaluation of raw and fermented water hyacinth (Eichhornia crassipes) incorporated diets on growth and feed efficiency of young grass carp (Ctenopharyngodon idella)

Abstract

The evaluation of raw and fermented water hyacinth Eichhornia crassipes (Mart.) Solms as dietary ingredient for young grass carp Ctenopharyngodon idella (Val, 1844) was carried out by adding 20% of each of the alternative ingredients separately to the control diet to completely compensate barley, a portion of wheat bran and 20% of fish meal. Results indicated that all growth and feed efficiency parameters among treatments were similar and there were no significant difference (p>0.05) in specific growth rate (SGR), food conversion ratio (FCR), protein efficiency ratio (PER) and protein productive value (PPV) of fish fed any of the diets. The diet containing fermented water hyacinth (WF) was found to be more efficiently utilized by fish and of highest digestibility values for all nutrients, which indicated that the digestibility was stimulated by incorporation of fermented water hyacinth. The raw water hyacinth diet (WR) produced significantly (p<0.05) highest satiation level associated with lowest digestible energy. Evacuation rate was not affected significantly (p>0.05) by the inclusion of raw or fermented water hyacinth to the diets. The protein, lipid and ash levels in carcass were higher in fishes fed the control diet (C). In conclusion, incorporation of raw or fermented water hyacinth up to 20% level was found to be suitable and there were no adverse effects on the growth and feed efficiency of experimental fishes.