Growth dynamics and compensatory mechanisms in fish under fasting and refeeding regimes

Fasting and refeeding strategies have gained prominence in aquaculture as management tools that may influence growth performance, feed utilization, and physiological status in cultured fish. This review synthesizes current research on the effects of controlled fasting and subsequent refeeding across multiple species, highlighting their impact on growth responses, and metabolic regulation. During fasting, many fish species exhibit reduced somatic growth, decreased feed utilization efficiency, and metabolic adjustments aimed at conserving energy reserves. Upon refeeding, some species demonstrate a compensatory growth (CG) response characterized by hyperphagia, accelerated weight gain, and shifts in nutrient allocation. This response has been associated, in certain species and experimental conditions, with modulation of growth-related gene expression, replenishment of hepatic energy stores, and partial recovery of biochemical indicators. The magnitude and efficiency of CG vary widely depending on fasting duration, refeeding strategy, species-specific metabolic capacity, life stage, and environmental conditions. Strategic implementation of fasting-refeeding protocols can reduce feed costs, mitigate overfeeding-related stress, and enhance sustainability in aquaculture operations. These findings support the integration of tailored fasting regimes into aquaculture management to maximize growth recovery, maintain metabolic health, and improve overall production efficiency.