Analyzing Biochemical Status of Cultivated Hydrobionts for Evaluation of Mariculture Sustainability

Abstract

The article touches upon the problem of sustainable development of the sea hydrobionts. Deep-sea scallop Mizuhopecten yessoensis is one of the most common breeding species in Primorsky Kray usually grown by two methods: cage and bottom. The cage (industrial) cul-tivation type is the most developed, but requires close attention. Improper planning of the mariculture development can affect the scallop survival, which in turn will lead to significant financial losses. Nowadays mariculture farms in different countries register the mass mortality of the cultivated aquatic organisms, the causes of this phenomenon being not clear, and often their identification requires a lot of time, as well as financial expenses. The use of prognostic mechanisms based on biomarkers can help identify the hidden threats in the body of cultivated scallops that lead to the mass mortality. The assessment of the state of mollusks at earlier stages of development will allow predicting and preventing significant losses of commercially valuable species. There have been analyzed the biomarker and scallop mortality rates of the scallop Mizuhopecten yessoensis cultivated by the cage method. Different groups of mollusks from 2 generations with the age difference of 10 years have been evaluated. In the course of the study it was found that with the increasing number of DNA defects and active accumulation of malondialdehyde in tissues the mortality of mollusks increases. It was stated that in scallops aged 1+ generations of 2015 there were registered the great number of DNA molecule defects and the high level of malondialdehyde concentration in the digestive gland and in the gills, which subsequently led to the mortality of almost all commercially valuable species aged 3+.