DIETARY SUPPLEMENTATION WITH DIFFERENT LEVELS OF SMALL PEPTIDES ON GROWTH, STRESS TOLERANCE, ANTIOXIDANT, AND IMMUNITY CAPACITY IN MACROBRACHIUMROSENBERGII ZOEAE LARVAE

To determine the optimal dietary inclusion level of small peptides for Macrobrachium rosenbergii zoeae larvae, five isonitrogenous and isolipidic experimental diets were formulated by adding small peptide protein at levels of 0 (SP0), 2.5% (SP2.5), 5% (SP5), 7.5% (SP7.5), and 10% (SP10), resulting in small peptide concentrations of 0, 0.98%, 1.97%, 2.95%, and 3.94%, respectively. A total of 125000 zoeae larvae [initial weight: (0.17±0.01) mg] from the same batch of spawners were selected and randomly distributed into 5 treatment groups, with 5 tanks (200 L each) per group and 5000 zoeae larvae per tank. The experiment lasted for 31 days. The results showed that the survival rate and post-larval yield rate in the SP2.5 group were significantly higher than those in the SP0 group (P