Preliminary physiological study on the edible wild bivalves in myeik, Myanmar

Abstract

To clarify the bivalve fishing situation in Myeik Coast, which is a well-known centre of coastal fishing in Southern Myanmar, an investigation on the physiological conditions of wild bivalves, hard clam Meretrix casta var. ovum (Hanley, 1845), soft clam Paphia undulata (Born, 1778), green mussel Perna viridis (Linnaeus, 1758), oyster Crassostrea belcheri (Sowerby, 1871), and pen shell Atrina pectinata (Linnaeus, 1767) landed in the City was done in December 2014, and March and September 2015. The bivalves were purchased at some local markets and a seafood restaurant, and their physiological conditions, including sexual maturation, food availability, and ability of nutritional absorption, were investigated through histological observations. Additionally, the concentration of paralytic shellfish poisoning (PSP) toxins was examined in the soft tissues of the bivalve samples with an enzyme-linked immune sorbent assay. The results showed that hard clam Meretrix casta var. ovum was the stable landing species through dry and wet seasons. Its spawning season was a long period extending from dry to wet seasons, ensuring good food availability and nutritional absorption. The concentrations of PSP toxins were low (<1 nM) in all bivalves, making them safe for human consumption. In conclusion, these results suggest that the Myeik Coast is suitable for hard clam fishing for the time being.