Development of a growth model for penaeid shrimp

An individual growth model for penaeid shrimp is presented. The main physiological processes simulated were: ingestion, assimilation, faeces production, respiration and female reproduction. The model was used to quantify the most important physiological processes involved in growth and also to examine the effect of food availability and water temperature on shrimp final weight. The simulation reproduces the typical pattern of growth of penaeid shrimp, characterised by a rapid weight gain during the early life stages and by the achievement of asymptotic length in adults. The ingestion and respiration rates increased as the animal grew but the weight-specific rates decreased with an increase of shrimp weight. A sensitivity analysis showed that the model does not produce differences at a 10% change in juvenile food availability. On the other hand, a change of water temperature of the same magnitude had an effect on shrimp final weight. The model was developed in the visual simulation software Powersim™. The individual growth model presented in this paper may be integrated into population dynamics models in order to simulate the biomass and density throughout the stages of the shrimp life cycle; such models may be usefully applied both to penaeid aquaculture and to management of wild fisheries.