Nature 241, 475 - 476 (16 February 1973); doi:10.1038/241475a0

Growth and Metabolism of Ostrea edulis Larvae

P. A. GABBOTT & D. L. HOLLAND

NERC Unit of Marine Invertebrate Biology, Marine Science Laboratories, Menai Bridge, Anglesey

ONLY a fraction of the plant food captured by zooplankton is converted into growth ; the rest is lost through incomplete assimilation, excretion and metabolism. The net growth efficiencies, K ₂ (percentage of assimilated food converted into growth) for haloplanktonic animals such as Calanus and related copepod species are generally lower than the percentage of assimilated food lost in metabolism (100-K ₂. In terms of calories, values of K ₂ quoted in a recent review by Corner and Davies¹ range from 23−58 for C. hyperboreus, from 6−55 for C. helgolandicus, and from 14−29 for Acartia clausi. There are few comparable estimates of growth efficiencies for meroplankton species, such as molluscan larvae, but the data that does exist suggests that the values of K ₂ are considerably higher than those for copepods. Jørgensen calculated a value for K ₂ of 73% for Mytilus larvae and values of 62% and 63% for two gastropod veligers², and from short-term feeding experiments with Ostrea edulis Walne estimated that 68−80% of the total food assimilated by the larvae is utilized for growth³. During larval development the daily level of assimilated food declined from 56% to 29% of the body weight.

References

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