Effect of salt stress on energy usage and growth in grass carp Ctenopharyngodon idella (Valenciennes, 1844) and common carp Cyprinus carpio L. juveniles

Abstract

The present study was conducted on two species of cyprinid fish: Common Carp (Cyprinus carpio) and grass Carp (Ctenopharyngodon idella). The study includes the effect of increasing salinity on survival rate, oxygen consumption, glucose and total protein levels in blood plasma, energy usage, food consumption and growth rate. Common carp show more resistance to increasing salinity with 90% survival rate in 15 g/l salinity. While grass carp did not survive increasing in salinity more than 5 g/L. Increasing salinity was accompanied with decreasing total protein in blood plasma, increasing blood glucose, increasing oxygen consumption rate and increasing energy usage. Food intake was also decrease with increasing salinity which results in decreasing growth rate for both fish species. This study showed that salt stress negatively affect food intake, energy usage and decrease growth rate.