Comparative Effect of Fish Feeds on the Initial Growth and Survival Rate of Juvenile Redbreast Tilapia (Coptodon rendalli) under Early Hatchery Conditions

Abstract

This study compared the effects of three supplementary diets—egg yolk, Artemia, and commercial pellets with 48% crude protein—on the growth performance and survival rate of redbreast tilapia (Coptodon rendalli) under intensive culture conditions at the Kamutjonga Inland Fisheries Institute in the Kavango East region of Namibia. The study was conducted from December 2023 to January 2024 using a complete randomized design replicated thrice. Results showed that fish fed with commercial pellets exhibited the highest specific growth rate (1.39 ± 0.80%) compared to egg yolk (0.94 ± 0.54%) and Artemia (0.33 ± 0.19%). Commercial pellets also had the best survival rate (76.19 ± 43.099), compared to egg yolk and Artemia (70.47 ± 40.69; 33 ± 19.05), respectively. However, egg yolk had the best feed conversion ratio (0.20 ± 0.05) compared to the commercial pellets (0.22 ± 0.04) and Artemia (0.26 ± 0.07). Critical water quality parameters were maintained within acceptable survival ranges for C. rendalli across all treatments. These findings highlight the importance of dietary protein content in optimizing the growth and survival of C. rendalli under intensive culture conditions and provide insights for effective feeding strategies. However, commercial pellets are expensive and inaccessible to small-scale fish farmers. As an alternative, egg yolk emerged as a viable and affordable feed option, promoting fish growth and supporting the establishment of small-scale farming practices in the region.