EFFECT OF LIMB AUTOTOMY ON THE INTERNAL PHYSIOLOGY AND BIOCHEMISTRY PARAMETERS, AND THE MOULTING PROCESS OF THE ORANGE MUD CRAB, Scylla olivacea.
Rusydi Rozaimi, Ghazali Azmie, Muhammad Achdiat, Hanafiah Fazhan, Khor Waiho

Abstract

Limb autotomy is one of the behavioural adaptations of mud crabs, which is to shed off their limbs when stressed or threatened by predators. The orange mud crab, Scylla olivacea, is the most abundant mud crab in Malaysia. They are one of the high valued seafood delicacies and have commercially important values in the fisheries and aquaculture sector. Moulting in mud crabs is directly related to growth and maturation, and is an important process in its culture and production. In this study, we evaluated the moulting process of S. olivacea at the intermoult stage following different degrees of limb autotomy. The physiology of the mud crab was affected by limb autotomy, such as its eating behaviour, growth rate, regeneration rate, and moulting. Limb autotomy affected feeding negatively but promoted growth and regeneration rate, especially for bilateral claw ablation followed by full limb autotomy. Also, limb autotomy will induce ecdysteroid production as ecdysteroid promotes the moulting process. Understanding how limb autotomy induces moulting will provide important basis for future development of artificial moult induction strategies.

Keywords: Autotomy- Portunids- Orange mud crab- Scylla olivacea

Topic: Sustainable Aquaculture and Fisheries