C and N gross efficiencies of copepod egg production studies using a Dynamic Energy Budget model
Kuijper, L. D. J., Anderson, T. R. and Kooijman, S. A. L. M. 2004.
C and N gross efficiencies of copepod egg production studies using a
Dynamic Energy Budget model J. Plankton Res., 26: 213 - 226
Abstract
A new model of copepod egg production is presented based on Dynamic Energy
Budget theory. The model splits substrates between nitrogenous and
non-nitrogenous compounds each with associated biochemical pathways,
distinguishes between structural and reserve components of animal biomass,
and requires that assimilated substrates are utilised to meet maintenance
costs prior to allocation for egg production. Conversion of substrates to
products is controlled by synthesising units. The model realistically
predicts the carbon and nitrogen gross growth efficiencies of egg
production by Acartia in response to food C:N. Production tends to be
maximised when consuming N-rich food, indicating a general N-limitation,
the benefits being greatest at high intake rates. However carbon in food
also plays a role in regulating egg production by favouring protein-sparing
biochemical pathways. The model indicates that zooplankton are unable to
utilise dietary N efficiently for egg production, even when it is scarce in
the diet, because of the N demands for maintenance. The work emphasises the
need to consider the separate C and N requirements for production and
maintenance, in conjunction with biochemical aspects of substrate
utilisation, in order to understand dietary constraints to zooplankton
production.