Social control of growth in Macrobrachium rosenbergii. V. The effect of unilateral eyestalk ablation on jumpers and laggards

Abstract

The effect of unilateral eyestalk ablation on Macrobrachium rosenbergii juveniles classified according to their relative rank was investigated. Jumper and laggard prawns were separately tested for the effect of ablation and sex on survival, daily weight gain, final weight, size increment per molt, molt interval and egg production. Survival of jumpers and laggards was about 95%. Eyestalk ablation had no effect on growth of male jumpers. Ablation had a highly significant effect on growth of male and female laggards, manifested in both increase in size increment per molt and shortening of the molt interval. The differential response of jumpers and laggards to eyestalk ablation is indicative of a different socially-determined growth related physiology. Some of the unexplained variability in growth and in rate of related energy metabolism of juvenile prawns (and other crustaceans with a wide size variation) could be due to their relative rank within their original populations.