Early Mild Stress along with Lipid Improves the Stress Responsiveness of Oscar (Astronotus ocellatus)

Early-life exposure to mild stressors can assist animals in coping with more stressful events later life. This study was aimed at investigating how early stress and dietary lipid contents affect growth, hematology, blood biochemistry, immunological responses, antioxidant system, liver enzymes, responses of oscar (Astronotus ocellatus) ( 6.8 ± 0.7 g). Six experimental treatments were HL0Stress (high-lipid diet without stress), HL2Stresses two-week HL4Stresses four-week LL0Stress (low-lipid LL2Stresses LL4Stresses stress). During the ten-week trial, fish fed high-lipid diets grew faster id="M2"> 46.41 4.67 vs. id="M3"> 38.81 2.81 ) had a lower feed conversion ratio (2.21 2.60) than those low-lipid id="M4"> P < 0.05 ). After acute confinement (AC groups higher survival (81.25% vs 72.92%) id="M5"> Fish subjected two-time (2Stresses) rate after AC (90.63% 62.50%), hematocrit, white cell, performance, total protein, high-density lipoproteins, cholesterol, triglyceride, alternative complement activity (ACH50), superoxide dismutase, glutathione peroxidase, alkaline phosphatase levels not stressed id="M6"> Contrariwise, glucose, cortisol, alanine aminotransferase, aspartate aminotransferase significantly 2Stresses compared 0Stress id="M7"> Collectively, these findings suggest stressing signs adaptation fish. However, number (4Stresses) appears exceed threshold manageable for this species. In conclusion, group outperformed other terms health status, responsiveness. Although welfare must be considered, results that result greater are exposed stress.