Effect of Vietnamese coriander Powder on Growth, Body Composition, Hematology, and Immune-Related Gene Expression in Nile Tilapia.

Dietary supplementation of plant herbs into aquafeed is recommended for intensive and sustainable aquaculture practices. This study has investigated the effect of Persicaria odorata (PO) leaf powder on growth, feed utilization, whole-body composition, hematology, and immune-related gene expression in Nile tilapia (Oreochromis niloticus). Fish (∼7.77 ± 0.01 g/fish) were randomly allocated into four treatment groups, each with three replicates. They were fed with dietary supplementation of PO at concentrations of 0, 15, 30, and 50 g/kg (termed PO0-PO50) for 10 weeks. Results indicated that the final body weight, weight gain, and specific growth rate were significantly higher at all PO supplementation levels compared to the control, with the highest value in the PO30 group. Similarly, the protein efficiency ratio and protein productive value in all PO groups were significantly higher than those of the control group. Red blood cells, white blood cells, and hemoglobin levels showed quadratic increases in the PO groups. In addition, total protein, globulin, and high-density lipoprotein cholesterol were linearly and quadratically increased with increasing PO levels, but alanine aminotransferase activity was linearly and quadratically decreased. Furthermore, dietary PO supplementation linearly decreased triglyceride and lipoprotein cholesterol levels, with the lowest levels found in the PO15 group. The expression of genes related to immunity showed that dietary supplementation of PO significantly increased the expression of proinflammatory factors (IL-1β and TNF-α), anti-inflammatory (IL-10 and TGF-β), and HSP70. In addition, glucose and cortisol levels decreased in all PO-supplemented groups, with the lowest levels found in the PO50 and PO30 groups, respectively. These findings showed that a dietary intervention with PO could improve growth, feed utilization, hematological parameters, upregulating genes related to immunity, and decreasing stress markers in Nile tilapia. Consequently, the utilization of PO at a dosage of 30 g/kg could contribute to the sustainable development of the aquaculture sector.