Enhancing growth of sea cucumbers Apostichopus japonicus by feeding fermented seaweed

Abstract

Laminaria japonica and Undaria pinnatifida are widely used as feed in the small-scale culturing of Apostichopus japonicus (sea cucumbers) because of their abundance and low price. However, the difficulty associated with the degradation of algin by Apostichopus japonicus and, hence, their utilization have limited practical value as feed in sea cucumber farming. In this study Apostichopus japonicus individuals were fed with Laminaria japonica and Undaria pinnatifida feed pretreated via fermentation with the algin-degrading bacterial strain GR2, 52 and 53. Their growth performance was then determined during 21 days period. Generally the sea cucumbers fed fermented seaweed showed better growth performance in terms of Weight Gain (WG), Specific Growth Rate (SGR), Feed Conversion Ratio (FCR) and Ingestion Rate (IR) compared to the one fed fresh seaweed. The results demonstrate that fermented seaweed in which the algin content had been degraded by bacteria could improve the growth performance of Apostichopus japonicus and hence be used as source of food in sea cucumber farming.