The aquaculture of decapod crustaceans is expanding continuously to supply protein source for human consumption. Therefore, intensive research is necessary to improve the quality of the feeds in decapod crustacean farming. Decapod crustaceans are slow feeders, and dietary inclusion of plant proteins reduces their intakes on the feeds. Dietary supplementation of chemoattractants (CA) (to reduce food searching duration) and feeding stimulants (FS) (to stimulate ingestion) is therefore necessary to

Tieshangang Bay in the Beibu Gulf, Guangxi of China, is a strategic location for pearl farming. Although water pollution has been reported in this bay but the general health of the pearl oyster, Pinctada fucata martensii, farmed there has never been assessed. The present study examined the condition of P. fucata martensii farmed in the Tieshangang Bay by analyzing its length-weight relationship (LWR) and relative condition factor (RCF). A total of 111 specimens were sampled for measuring their shell height and total weight for determining the LWR and RCF. The coefficient of correlation of the LWR was high (R2 = 0.93), significant at 0.01 level. Negative allometric growth (b = 2.7048) was observed. However, P. fucata martensii achieved the expected growth in terms of weight, as determined through the RCF (mean 1.13). Negative allometric growth is commonly reported on the wild Pinctada spp. collected from different regions. Apparently, the water pollution in the Tieshangang Bay did not compromise the general health of the pearl oyster cultured there. Nevertheless, further study on the farm’s surrounding water quality and plankton availability is necessary to investigate the interaction between the growth of the oyster and its culture environment. In conclusion, the P. fucata martensii farmed in the Tieshangang Bay was considered healthy and the bay is still suitable for pearl oyster farming.

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Scylla mud crabs are economically important portunid species for aquaculture in many countries. However, mass production of mud crabs as a supply of seafood is still difficult up-to-date. This review aimed to provide an overview of the major constraints faced in the grow-out farming of mud crabs, and the potential solutions were discussed. The major constraints in the Scylla mud crabs' grow-out culture are (1) inadequate seed supply, (2) cannibalism, (3) disease outbreaks, and (4) no commercial formulated feed that is specifically designed for mud crabs. The inadequate wild mud crabs seed supply can be solved through artificial seed production seed in the hatcheries, but the knowledge of mud crab requirements at early life stages is needed to improve the rearing techniques and production. Cannibalism in the grow-out culture of mud crabs is manageable, provided that the farmers are knowledgeable about the basic prevention methods (shelter provision, size grading, monosex culture) and they are practicing it. On the disease outbreaks, research into discovering new alternatives to antibiotics and prevention methods should be prioritized. Finally, the commercial formulated grow-out diet that is specific for the Scylla mud crabs should be developed to replace the use of natural products for feeding.