Effects of dietary tea tree (Melaleuca alternifolia) oil and feeding patterns on the zootechnical performance and nonspecific immune response of the giant freshwater prawn (Macrobrachium rosenbergii)

This study investigated the effects of dietary tea tree oil (TTO) supplementation and feeding patterns on the growth and nonspecific immunity of Macrobrachium rosenbergii. Prawns were randomly assigned into four patterns. Patterns 1 (P1) and 4 (P4): prawns were fed with a basal diet and basal diet supplemented with 100 mg/kg of TTO, respectively; Patterns 2 (P2) and 3 (P3): prawns were fed with the basal diet supplemented with 100 mg/kg of TTO at 1- and 2-week intervals, respectively. A significant increase in growth performance was observed in the P3 and P4 compared with P1. The activities of antioxidant enzyme were significantly elevated in the P3 and P4 compared with the P1. The concentration of haemolymph malondialdehyde was significantly lower in the P3 and P4 than the P1. The haemolymph level of IL-1 and TNF-alpha was significantly lower in the P3 than the P4. The expression of toll and dorsal was significantly lower in the P3 than the P1. However, the expression of peroxiredoxin-5 was significantly higher in the P3 than the P1. Overall, these findings indicated that feeding 100 mg/kg of TTO at 2-week intervals significantly improved the growth performance and nonspecific immunity of M. rosenbergii.