Insights into the molecular response mechanisms of fasting stress and refeeding in channel catfish (Ictalurus punctatus) through transcriptome and histological analysis

Throughout their life cycles, many fish alternate between periods of fasting and feeding due to the temporal and geographical variability of food availability in aquatic environments. The ability to adapt to starvation and restore internal balance after refeeding is fundamental to the long-term survival and symbiotic relationships of aquatic species. Among the organs affected by fasting, the liver is one of the first to respond, playing a central role in various physiological processes. Similarly, the intestine, as the primary site of nutrient absorption, is crucial in these adaptive processes. However, our understanding of the mechanisms by which the liver and intestine adapt to starvation and refeeding remains limited. To elucidate the molecular response mechanisms to fasting stress and refeeding in channel catfish, an important commercial species, we investigated their growth performance, liver and intestinal histology, and liver gene expression patterns during the fasting and refeeding phases.