Optimizing white shrimp aquaculture: Feeding frequency and automatic feeders impact on growth and antioxidant capacity

Abstract The feeding regime is a critical aspect of white shrimp ( Litopenaeus vannamei ) aquaculture, but research on intensive shrimp culture using automatic feeders is scarce. Our study investigated different feeding strategies for adult white shrimp in intensive aquaculture tanks, evaluating growth, survivability, feed utilization, shrimp digestive and antioxidant capacity, and conducting an economic analysis. Shrimp (8.0 ± 0.5 g) were cultured for 35 days with feeding frequencies of 6, 8, 10, and 12 times/day (A6, A8, A10, and A12 groups, respectively) using automatic feeders, and one group was fed manually 6 times/day (M6). The results show that the automatic feeding groups had a higher final body weight and specific growth rate, and a lower feed conversion ratio compared to the manual group. Among the automatic feeding groups, A6 and A8 exhibited the best performance, with a quadratic regression suggesting 7.83 times/day as an optimal feeding frequency. Digestive enzyme activity (TP and α-AMS) was significantly higher in the A6 and A8 groups ( p < 0.05). However, the A6 and A8 groups showed significantly higher levels of antioxidant enzymes (SOD and GPx) and lower levels of lipid oxidant enzyme (MDA), indicating better digestive and antioxidant abilities in shrimp with higher growth rates. Moreover, the antioxidant genes expression of MnSOD and GPx testified the enzyme changing. Pearson's correlation confirmed the positive correlation between SOD and GPx. Economically, the A8 group showed the highest profitability among all groups. Overall, the study recommends a feeding frequency of 6–8 times/day using automatic feeders as a suitable and feasible approach for white shrimp culture in intensive settings.