Effects of intermittent starvation on the survival, growth, and nutritional status of the freshwater prawn Macrobrachium borellii Nobili, 1896 (Decapoda: Caridea: Palaemonidae)

Abstract

We examined the effect of the double restriction-recovery cycle on survival, growth, and nutritional status of the freshwater prawn Macrobrachium borellii (Nobili, 1896), native to floodplain rivers of Argentina. The restriction period consisted of intermittent starvation (alternating four-day feeding with no feeding for four days) and a recovery period of continuous feeding following the restriction period. Survival was high over a 20-week trial with cycles of food scarcity. Prawns showed a slight impact on their growth throughout the entire first cycle of restriction-recovery; however, compensatory growth was not triggered. The reduction of growth was markedly more drastic after the second restriction period, but compensatory growth was not exhibited when the second recovery period was reestablished. Any possible impact of the double cycle of intermittent starvation on energy reserves and structure of the hepatopancreas was compensated by a posterior cycle of continuous feeding. The results demonstrated that M. borelli can successfully support long-term food scarcity throughout the juvenile and adult phases, at least intermittently and followed by a recovery period. The high nutritional flexibility is an adaptation to fluctuations in food availability and an advantage for successful ornamental aquaculture.