Oxygen consumption and ammonia excretion during the molt cycle of the freshwater prawn Macrobrachium rosenbergii (De Man)

1. 1. Using metabolic indices, molt staging was determined for the freshwater prawn Macrobrachium rosenbergii. 2. 2. The rate of weight specific oxygen consumption (QO₂) was lowest during the intermolt stage, with values of 1.39 ml O₂/g per hr. Oxygen consumption increased during the premolt and molt stages to values exceeding 3.0 ml O₂/g per hr. 3. 3. The rate of ammonia excretion increased from 17.5 μg NH₃-N/g per hr during the intermolt to 39.3 μg NH₃-N/g per hr during the premolt to molt stages.