Breeding Technique and Embryonic Development of Mud Crab, Scylla Serrata

Abstract

Scylla serrata, commonly referred to as mud crabs, is an important species, both as a food item for local consumption as well as a commercially exportable product. The natural resource of this species is gradually declining due to human intervention and environmental modification that made the species a threatened one. Bringing this species into culture system can be a strategy to prevent it from being dwindled in the nature. With this aim in view, this study was conducted to know the brood development, breeding techniques and embryonic development of the species followed to develop a successful hatchery technology. The experiment was conducted "Sundarban Golda Hatchery" in Khulna. Ten brood crabs were collected from Munshigong crab farm and the average weight of crab was 180g. During breeding at hatchery salinity, temperature and pH of water were 30 ppt, 26 to 28 °c and 7.5 to 7.6 respectively. Matured brood crabs were hatched within over night. From the study, the average fecundity of the specimens was counted approximately 10, 00,000 and the average hatching was 4000 per 8 individual, hatching rate was approximately 5%. The embryonic development was checked and only one stage named blastula was possible to observe because of high embryo mortality. During larval rearing, newly hatched zoea was also observed. As the species is being rapidly declined from the natural waters, attention must be taken for bringing it under culture system and for adhere package in the larvae production and hatchery management technologies are necessary. This results promoted and be deemed as initial in this regard necessitating alternatives for conservation of the species.