The effects of different feeding strategies on the domestication of juvenile Chinese perch <i>Siniperca chuatsi</i>

Domesticating Chinese perch to accept formulated feed is crucial for its industrial aquaculture. However, standardized feeding protocols for each domestication stage remain underdeveloped. This study investigated optimal feeding strategies and the underlying physiological pathways involved. The feeding rate experiments (5%, 8%, 11%, 14%, 17%) found that the relationship between feeding rate and domestication rate was modeled as Y=-0.5291X 2 +14.119X-23.814, with an optimal rate of 13.34% attributed to appetite stimulation via moderate starvation. Conversely, low-feeding rate induced oxidative stress, reducing the domestication rate. The feeding frequency experiments (2, 3, and 4 times/d) showed 2 times/d aligned with the natural bimodal feeding rhythm, yielding better domestication. While 4 times/d markedly enhanced feeding-related learning and memory, as indicated by upregulated fosl2 expression and increased attack frequency. However, the oxidative stress resulting from deviations from innate circadian rhythms ultimately outweighed these benefits, thereby hindering the domestication process. The feeding duration experiments (2, 4, 6, and 8 d for chilled baitfish) exhibited a significant decrease in oxidative stress after feeding for more than 6 d, which improved the acceptance of subsequent artificial feed. Moreover, the expression of learning and memory-related gene syt4 and the attack number were significantly up-regulated after feeding for 8 d, indicating enhanced feeding memory for artificially fed food. Thus, prolonging chilled baitfish feeding could enhance feeding response by increasing learning and memory, and reducing oxidative stress, thereby boosting domestication effects. Collectively, an optimized strategy (13.4% feeding rate, 2 times/d frequency, &gt;6 d chilled baitfish feeding) achieved a higher domestication effect, providing a scientific basis for standardizing domestication and optimizing feed formulations.