Sex Control in Cultured Decapod Crustaceans

The increasing demand for decapod crustaceans in the aquaculture market has elicited the need to develop more intense production methods in order to increase yields and profits. One promising approach to increase cultured decapod crustacean yields is through the use of monosex populations. In species that exhibit male superiority, an all-male population, in which males grow faster and are larger in size at harvest, is more profitable. Likewise, all-female populations are preferred in species with female superiority, where females are larger at harvest. All-female populations are also beneficial under intensive aquaculture conditions in species where male-like aggressive behavior prevents stocking at higher densities. In addition to their commercial benefits, decapod monosex populations are suggested to be sustainable pest control agents against the agricultural, environmental and human hazards borne by pest snails. Understanding the controlling mechanism behind sexual determination and differentiation in decapod crustaceans can promote the development of novel biotechnologies to achieve stable monosex populations. A fundamental role in the sexual differentiation process is attributed to the androgenic gland (AG), a unique crustacean endocrine organ whose formation or implantation is followed by masculinization, and whose absence or ablation results in feminization. Sex reversal in crustaceans, therefore, a mandatory prerequisite for the achievement of monosex populations, could be achieved through manipulation of the AG. This chapter will discuss the development of decapod crustaceans from the point of genotypic sex determination upon fertilization, through the sexual differentiation process, and until complete sexual maturation. In addition, existing novel biotechnologies to achieve monosex populations in decapods by manipulating the sexual differentiation process will be described.