Sex Reversal of the Giant Freshwater Prawn Macrobrachium dacqueti through Androgenic Gland Ablation

Abstract

The male Macrobrachium species (giant freshwater prawn) typically achieve better growth and a larger harvest size than females. Hence, it is clear that the monosex culture of all-male prawn populations would be inexpensively advantageous. This study aimed to determine whether androgenic gland (AG) ablation induces sex reversal of giant freshwater prawn Macrobrachium dacqueti. The AG of the prawn was ablated through bilateral microsurgery (AG ablation) and let them recover for two months. The weight and length were also measured every 15 days. Results revealed that the removal of AG from the males of immature M. dacqueti resulted in sex reversal, with 70% female differentiation. Successful neo-female prawns exhibited the development of an ovary with orange coloration as it matures. Andrectomized M. dacqueti did not develop the appendix masculina in the second pleopod, an indicator of a suspected neo-female prawn. A significant increase in weight and length was observed within two months compared to the control. Based on the result of the study, sex reversal of M. dacqueti is possible through AG ablation. Therefore, sex-reversed (neo-females) M. dacqueti can be used to breed with normal males to produce all-male progenies since both parents possess male hormones, thereby rendering a huge advantage for prawn culture.