Cage culture of Larimichthys crocea(large yellow croaker)is developing rapidly in China,bringing great economic benefit.However,the high frequency of disease outbreaks,limited available coastal land and ocean pollution threaten healthy culturing of L.crocea.Low-salt aquaculture at inland facilities may provide a solution to these problems.This study explored the effect of salinity on the survival,growth and otolith metal content of cultured L.crocea.In March 2016,healthy L.crocea [(average body weight,(0.083±0.022)g;body length,(1.55±0.16)cm]were selected for a 180-day culture experiment.Five salinity groups(2,4,6,8,24 mg/g)were tested and each treatment was run in triplicate,with 20 000 test fish for each treatment.Salinity,initially at 24 mg/g,was directly decreased to 8 mg/g,and then decreased by 2 mg/g each day to give treatment levels of 6 mg/g and 4 mg/g and the 2 mg/g treatment level was obtained by decreasing salinity 1mg/g per day.Test fish were fed twice a day at 2%-5% of body weight.During the experiment,water temperature was measured each day and,on the sixth day of each month,50 L.crocea were randomly sampled for measurement of body length and weight.The metal content(Sr,Ca,Mn,Fe,Co and Ba)of otoliths in each group were determined after the 180-day experiment.The survival rate of the indoor cultured L.crocea decreased with increasing water temperature,but lower salinity enhanced survival at higher temperatures.L.crocea at 24 mg/g salinity all died at a water temperature of 28℃,but the survival rate at 2 mg/g salinity(68.8±2.89%)was significantly higher(P<0.01)than in other salinity groups at 30℃.The quality,absolute growth rate,absolute weight gain rate and fatness of fish in the low-salinity treatment groups were higher than in the normal salinity group(24 mg/g).Otolith content of Mn,Ca,Sr and Sr/Ca was positively correlated with salinity(P<0.05),but no correlation was found between Fe,Co,Ba and salinity
