NUTRITIONAL-VALUE OF DRIED ALGAE DIETS FOR LARVAE OF MANILA CLAM (TAPES-PHILIPPINARUM)

Spray-dried Nannochloris sp. and Tetraselmis suecica were fed to larvae of the Manila clam (Tapes philippinarum). These dried diets supported growth equal to, or greater than, their live algal counterparts, but less than a control diet, a mixture of two algae species of known high nutritional value (Chaetoceros calcitrans and T-ISO). Larvae were grown through to metamorphosis on the dried Nannochloris sp. diet in 21 days, compared with 8–11 days with the control diet. Using dried Nannochloris, it was shown that T. philippinarum larvae do not have an essential requirement for long-chain (20 and 22C) polyunsaturated fatty acids, but are able to synthesize them from shorter chain (18C) fatty acids present in the diet. The higher total carbohydrate content of the dried algae was reflected in the larvae feeding on this diet. © 1990, Marine Biological Association of the United Kingdom. All rights reserved.