Despite the local availability of protein rich peanut-based ingredients, fish meal has persisted as the
conventional source of dietary protein for aqua feeds in Uganda. A 20-week field experiment was
conducted in to determine the Relative Growth Rates of Nile tilapia fish fed on fish meal and peanutbased
diets in earthen ponds at Busoga University farmland in Iganga district of Eastern Uganda. Sixweek
old juvenile fish of mean weight of 22.0 grams were stocked and fed at 5% of their body weight
(BW) daily. Three test diets were utilized namely the fishmeal (FM)-based diet and the peanut based
diets which included; peanut meal (PNM)-based diet & mixed plant meal (MPM)-based diet. The
existing locally available commercial feed (CF) for Nile tilapia acted as the control diet. Although the
mean Relative Growth Rate (RGR) of fish fed on the FM-based diet was the best, it was not significantly
different (p0.05) from that fed on the MPM-based diet. A significant difference (p0.05) in mean
RGR’s existed between the FM and PNM-based diets and between MPM and PNM-based diets. Basing
on the RGR’s of the experimental fish, the MPM-based diet should completely substitute fish meal in the
diet of Nile tilapia.