PCA biplot of growth and reproductive parameters across dietary treatments (SM0–SM50). Points denote treatments; colored ellipses show k-means clusters. Arrows indicate variable loadings: FW (final weight), WG (weight gain), SGR (specific growth rate), FE (feed efficiency), PER (protein efficiency ratio), TL (total length), GSI (gonadosomatic index), EG (egg production), FR (fertilization rate), and HA (hatching rate). PC1 and PC2 explain 85.5% and 12.6% of total variance, respectively.

Principal component analysis (PCA) of SM0 and SM50 samples. Each circle represents an individual biological replicate (SM0_R in light-blue, n = 3; SM5_R in light-pink, n = 3). The x- and y-axes correspond to PC1 (82.2% of total variance) and PC2 (7.9% of total variance), respectively, showing clear separation between the two conditions.

Volcano plot of SM50 vs. SM0. Down regulated genes are shown as light blue (cyan) dots (n = 813), up regulated genes as light orange (peach) dots (n = 1486), and non-significant DEGs as gray dots (n = 5219). The vertical dashed lines mark log₂ (fold-change) cutoffs, and the horizontal dashed line the significance threshold (p = 0.05).

Functional analysis of DEGs based on RNA-Seq data. The results are summarized in the ten most enriched GO terms within three main categories: cellular component, biological process, and molecular function.

Bubble plot representing the main enriched pathways according to the KEGG analysis. The Y-axis indicates the enriched pathways, while the X-axis represents the enrichment score.

KEGG pathway maps show differential gene expression in SM50 vs. SM0. (A) Ribosome: maps of the large (top) and small (bottom) ribosomal subunits. (B) Oxidative phosphorylation: complexes I–V of the mitochondrial electron-transport chain. In both panels, genes are colored according to their log₂(fold-change): shades of red denote upregulation, shades of green denote downregulation, and gray denotes non-significant changes. The color bar in the upper right shows the log₂ (fold-change) scale.