Sustainable replacement of fishmeal with Artemia biomass in diets for Nile tilapia ( Oreochromis niloticus )
Mary A. Opiyo, Morine M. Ngarari, Sheban Mdzomba Hinzano, Francis Akatsa Okalo, Charles Amahwa Omuholo, Daisy Nyawira Muriuki, Betty NyonjeABSTRACT
This study evaluated the effects of substituting fishmeal with Artemia biomass in aquaculture diets on growth performance and whole‐body composition of Nile tilapia ( Oreochromis niloticus ). Four dietary treatments were administered in triplicate to juvenile Nile tilapia (44 g) stocked in 1m 3 cages in a pond at 30 fish per cage for 84 days. The diets were AT 0 (0% Artemia biomass), AT 50 (50% replacement), AT 100 (100% replacement), and COMM (Commercial pellets). Initial measurements showed no significant differences in fish length and weight across treatments ( p > 0.05). However, final assessments revealed that fish fed AT 100 and COMM diets exhibited significantly higher final weights, specific growth rates (SGR), daily weight gains (DWG), and percentage weight gain (WG%) compared to those on AT 0 and AT 50 diets. Additionally, feed conversion ratios (FCR) and protein efficiency ratio (PER) improved with increased Artemia inclusion. Whole‐body composition analysis showed significantly higher protein and lipid contents and lower moisture and ash contents in fish fed the AT 100 and COMM diets, while carbohydrate content remained similar across all dietary treatments. These findings demonstrate that total replacement of fishmeal with Artemia biomass (AT 100 ) supported growth performance, survival, feed conversion, and whole‐body composition. Future studies should assess nutrient digestibility, physiological welfare indicators, and economic efficiency across tilapia strains and culture systems to validate its broader commercial applicability.