Effects of unilateral eyestalk ablation on oxygen consumption and ammonia excretion of juvenile Penaeus japonicus Bate at different salinity levels

Abstract

Oxygen consumption rate (O-2 mg/g/h), cumulative oxygen consumption (O-2 mg), ammonia excretion (N mu g/g/h), and cumulative ammonia production (N mu g) were examined for eyestalk-ablated and intact juvenile Penaeus japonicus Bate (0.69 +/- 0.14 g) at 20, 30, and 40 ppt salinity. Following eyestalk ablation, the shrimp increased its cumulative oxygen consumption only at 20 ppt, and increased its ammonia excretion and cumulative ammonia production at all salinity levels tested. Relationships among oxygen consumption, ammonia excretion, cumulative oxygen consumption, cumulative ammonia production, salinity, and exposure time are given. It is concluded that unilateral eyestalk ablation significantly affects nitrogen metabolism in P. japonicus.