On some factors affecting molting and growth rate of the giant freshwater prawn, Macrobrachium rosenbergii (De Man, 1879)

The effect of temperature (20, 25, 30 and 35 ºC), salinity ( 0, 5, 10 and 15 ppt), pH (6, 7, 8 and 9) and light (24h L:00hD, 12hL:12hD and 00hL:24hD) on molting cycle, growth and survival of larvae of the freshwater prawn Macrobrachium rosenbergii were investigated independently under laboratory conditions. Temperature, salinity and pH significantly (P<0.05) influenced the molting, growth and survival of the prawns. The influence of photoperiod was not significant (P>0.05). The best levels of temperature, salinity and pH, which gave the fast molt with the highest growth increment in M. rosenbergii were 30ºC, 5 ppt, and pH 8, respectively. Outside these levels, more molting did not produce more growth. These results have direct implications in the aquaculture production of Macrobrachium rosenbergii and accelerate the growth of prawns in conditions of intensive culturing with a reduction in production costs.