Impact of altered pH media on mortality rate, oxygen consumption and excretion in prawn, Panaeus monodon

摘要

Panaeus monodon of body weight 6.0 +- 0.5gm were selected to study the mortality rate, mean survival time, consumption, unit metabolism, excretory pattern of prawn on exposure to different ranges of both alkaline and acidic pH media. At pH 3.5 and pH10.5 highest mortality (100%) and least mean survival time were observed. At pH 4.5, 50% mortality and 72hrs of mean survival time was recorded, where as at pH 10.0 mortality rate was 20% and mean survival time was 96hrs. At pH 5.5 to 9.0 at the every interval of pH 0.5, mean survival time was highest. O_2 consumption, unit metabolism, ammonia, ammonia/ oxygen were estimated. O_2 consumption and unit metabolism were reduced in both acidic and alkaline exposed prawns over control. However, the reductionis less in alkaline exposure. But the ammonia content was showed opposite trend in both groups. In acidic exposed prawns the reduction was significant and considerable elevation was seen in alkaline exposure and ammonia/oxygen ratio also showed similartrend.