The Israeli Journal of Aquaculture - Bamidgeh 55(4), 2003
The 7th Annual Dan Popper Symposium


DOES THE ANDROGENIC GLAND PROMOTE GROWTH IN THE
FASTER-GROWING MALE CRAYFISH IN AN INTENSIVE
SEPARATED CELL SYSTEM?


Rivka Manor¹, Ran Segev², Eliahu D. Aflalo¹, Dudu Azulay¹ and Amir Sagi ¹*

1 Department of Life Sciences and the Institute for Applied Biosciences, Ben Gurion University of the Negev, P.O.Box 653, Beer Sheva 84105, Israel
2 Aquaculture Unit Negev-Arava Research and Development, Yair, D.N. Arava, 86825, Israel


Abstract

In several crustacean species, such as the Australian red claw crayfish Cherax quadricarinatus, males grow faster than females. In the process of exploring ways to intensify crayfish culture, a growout system of individual cages was designed. The growth rate of the males in these systems was significantly higher than that of the females. These results suggest that C. quadricarinatus males grow larger than females, even when there is no social interaction. An intrinsic factor is thus suggested in the form of the androgenic gland hormone. It has been suggested that the androgenic gland is the exclusive source of the hormone responsible for sex differentiation in crustaceans. The androgenic gland in crustaceans promotes male sex differentiation and inhibits female characteristics. The androgenic gland of C.quadricarinatus was identified and described in our laboratory. To investigate the role of the androgenic gland on growth and development of secondary and primary sexual characters in C.quadricarinatus, androgenic glands were implanted into young females. The growth rate of the implanted females was significantly higher than that of the control females, and the implanted females developed secondary male characteristics such as the red patch on the propodas as early as the second molt after implantation. These results support the hypothesis that growth in male crayfish is promoted by the androgenic gland.

E-mail: sagia@bgumail.bgu.ac.il


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