Manipulated yeast diets and dried algae as a partial substitute for live algae in the juvenile rearing of the Manila clam Tapes philippinarum and the Pacific oyster Crassostrea gigas

• Main Authors: Coutteau, P., Dravers, M., Dravers, P., Léger, P., Sorgeloos, P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 1993
• Subjects: Pacific; Crassostrea gigas; Pacific oyster
• Online Access: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=14750

The development of a cost-effective artificial diet would greatly reduce the operating costs and improve the efficiency of bivalve seed production. The present study documents the use of a manipulated yeast diet and dried algae ( Tetraselmis suecica, Cyclotella cryptica ) as an 80% substitute for live algae under the conditions of a commercial bivalve hatchery. Juveniles of the Manila clam T. philippinarum and of the Pacific oyster C. gigas were grown in a 28l recirculating system for three weeks. In addition, a preliminary flow-through culture test was performed with C. gigas . Supplementing manipulated yeasts improved the growth rate of juvenile clams and oysters fed 20% of the algal ration from 30-40% to 70-80% of that observed for the algae-fed controls over a period of 3 weeks. The yeast diet supported similar clam growth as the dried T. suecica and better oyster growth than the dried C. cryptica . Substituting 80% of the algal ration by either the yeast diet or dried T. suecica in the flow-through experiment with C. gigas resulted in a growth rate exceeding 90% of that observed for the algae-fed controls during the first week of the experiment. During the second week of the test this relative growth rate was only maintained by oysters fed the 20/80% algae/dried T. suecica diet. Further research is needed to define the optimal food levels of the yeast diets in continuous flow cultures.