Postprandial metabolic changes in larval and juvenile carp (Cyprinus carpio).

Ammonia-nitrogen excretion and oxygen consumption rates after a meal were followed in carp larvae and juveniles of different sizes, starting from early exogenous feeding and until they had reached about 1 g of body weight. There was an immediate rise in the nitrogen excretion rate after feeding; the amplitude and duration of this increase were affected by body weight (BW) and the amount of nitrogen consumed (NI) and could be described by the equation: 37.61 BW-0.311 NI0.802. Endogenous nitrogen excretion rate and basal metabolic rate were affected by both nutritional status and previous nutritional history. A model used to describe the postprandial nitrogen excretion pattern in young carp fitted well with the experimental data. The different coefficients of the model were affected by body weight.