Toward Context‐Appropriate Feed Processing in Aquaculture: Evidence From a Meta‐Analysis of Extrusion and Pelleting

Feed processing technology choice between extrusion and pelleting remains a critical decision in aquaculture nutrition. We conducted a systematic review and meta‐analysis of 40 comparisons from 23 studies to evaluate the growth performance effects of extruded versus pelleted feeds. While conventional random‐effects models indicated an overall benefit of extruded feeds (Hedges’ g  = 0.97, 95% CI: 0.49–1.45), extreme heterogeneity ( I 2 > 99%), and a nonsignificant multilevel model accounting for study dependencies ( g  = 0.53, p = 0.075) revealed context‐dependent effects. Meta‐regression identified species identity as the primary moderator, explaining 62.1% of heterogeneity. Nutritional composition was also significant: dietary lipid content improved growth, while higher ash content in extruded diets reduced efficacy. These findings demonstrate that feed processing outcomes are not technology‐inherent but are mediated by species‐specific biology and nutritional interactions. Optimal feed selection should, therefore, prioritize integrated consideration of species requirements and nutritional formulation over processing method alone.