Acclimation Trial of Liza aurata Fingerlings To Fresh Water and To a Low Water Salinity

This study was conducted to investigate the effect of abrupt and gradual acclimation of Liza aurata fingerlings to fresh water and gradual acclimation to a selected salinity 3‰.L.aurata fingerlings were collected directly from the sea and duplicate groups of 30 fingerlings were distributed after rest to glass aquaria (100 liter capacity). The first group was acclimated abruptly to fresh water, the second gradually to fresh water, the third was acclimated gradually to 3‰ and the last group was left as control in sea water. The fingerlings were fed artificial diet (35% protein and 500 kcal GE/100g), twice a day to satiation for 75 days. The results revealed that the first and the second group of fingerlings died gradually showing the same symptoms including stress, dark coloration, loss of appetite and abnormal swimming behavior. While the fingerlings in the third aquarium stayed alive to the end, and even their growth rates and feed utilization efficiency were comparable (P 0.05) to those lived in sea water.