The androgenic gland (AG) is a unique gland present in male crustaceans and is known to influence male sexual differentiation. The separation of the AG with endocrine function and testis with gametogenic function offers a unique model for investigation into mechanisms underlying sexual differentiation in the animal kingdom. In this study, the role of the AG in sexual differentiation was investigated with the aim of achieving an all female population in Penaeus monodon. The AG in P. monodon was identified and localized as a gland attached to the sub terminal part of the terminal ampoule (TA) and extends to the coxal muscle of fifth pereopod. The activity of the AG is thought to be negatively regulated by the X-organ-sinus gland (XO-SG) in the eyestalk and its secretory product is believed to be proteinaceous. Elucidation of the ultrastructural changes within the AG cells upon XO-SG removal, shed light on its protein secretory nature and exocytotic mode of secretion.
Submitted in the fulfilment of the requirements of the degree of Doctor of Philosophy, University of the Sunshine Coast, 2011.