Performance Traits and Expression of Growth‑Related Genes of Clarias gariepinus Fed Conventional and Non-Conventional Feed Ingredients

This study investigated the impact of conventional (commercial) and nonconventional diets, specifically containing hydrolyzed feather meal (HFM), crustacean waste (CW), and chicken viscera (CV), on performance traits and insulin growth factor 1 (igf-1)/ growth hormone gene (ghg) expression in African catfish (Clarias gariepinus), with an average initial weight of 5.36 ± 0.03g. Eight diets were formulated, including a control diet and a commercial diet containing 37% crude protein, and administered in triplicate over a six-month feeding trial. Total RNA was extracted from liver samples via the Quick-RNA Miniprep Plus Kit, followed by real-time quantitative polymerase chain reaction (RT‒qPCR). The results revealed that gh mRNA expression levels were significantly increased by the CV, CW, HFM, and commercial diets, whereas igf-1 expression was notably increased by the HFM and HFM + CV diets compared to the control. A significant difference was detected in gh/igf-1 cycle quantification (Cq) (P< 0.05), when compared to the control. Among the diets, the HFM + CW combination resulted in the highest gh/igf-1 gene expression. The highest final weight gain (108.9 ± 0.007g), specific growth rate (2.32 ± 0.003%/day) and lowest feed conversion ratio (1.30±0.003) were recorded for the fish fed the HFM + CW diet. The fish fed diets supplemented with 8.43% CW and 8.43% HFM presented increased growth rates and increased expression of gh/igf-1. The incorporation of HFM + CW in aqua-feed formulations modulated growth performance and GH/IGF-1 expression in Clarias gariepinus, contributing to sustainable aquaculture practices.