Study on salinity tolerance and oxygen consumption of silver pomfret(Pampus argenteus)larvae

Abstract

The salinity tolerance and oxygen consumption of Pampus argenteus larvae(2 days after hatching and 4 days after hatching)were investigated at salinities of 5,10,20,30,40,50,55.Mortality,mean death time(MDT),median death time(DT50),median lethal salinity-48 h(MLS-48),and survival activity index(SAI)were employed as indices of salinity tolerance,and individual oxygen consumption was detected by respirometer.The results showed that lower(5)and higher(above 50)salinities were detrimental to P.argenteus.MLS-48 for 2-day-old larvae and 4-day-old larvae ranged from 8.15 to 24.90 and 15.54 to 34.97,respectively.DT50 and MDT of 2-day-old larvae in 10-30 environment were significantly higher than other salinities,while DT50 and MDT of 4-day-old larvae were higher in 10-40.SAI of 2-day-old larvae in 10 and 20 environment were significantly higher than other salinities,while the better value of SAI in 4-day-old larvae was in 20-30,and salinity of 20 was the best one for both kinds of larvae.From the results of individual oxygen consumption,for larvae among the suitable salinity ranges(10-30),there was no significant difference between salinities,but higher salinities caused higher oxygen consumptions of larvae.The results indicated that the optimum salinity range of P.argenteus was 15.54-24.90,and higher salinity can cause an increase of oxygen consumption in P.argenteus larvae,but there was no significant effect among tolerant salinity range.