Effect of salinity on embryonic and larval development of cobia(Rachycentron canadum)
SUN Li-hua1,2, CHEN Hao-ru1,2, WANG Zhao-ding1,2
1. Marine biology Research Station at Daya Bay, Chinese Academy of Sciences, Shenzhen 518121, China; 2. South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
The sinking and floatation of fertilized eggs and the hatching rates and abnormal rates of eight broods of fertilized eggs under different salinities(20,23,26,29,32,35,38,41 and 44)were observed and compared,and the SAI(survival activity index)values of larvae were evaluated under different salinities(10、14、18、22、26、30、34、38、42和44)for cobia.The results showed that the fertilized eggs entirely sank in the seawater with salinity lower than 26,and entirely floated in the seawater with salinity higher than 32.The suitable salinity for hatching was from 26 to 41 and the optimum was from 29 to 38.The ranges of 23~26 and 41~44 might be two critical salinity causing notable differences in hatching rate of fertilized eggs and abnormal rate of newly hatching larvae.The SAI values of cobia larvae in different salinities were 2.32~16.24.The suitable salinity range for larvae survival activity was 22~38 and the optimum was 26~34 according to SAI values.The salinities from 18 to 22 and from 38 to 41 might be two critical ranges causing notable differences in SAI values.
孙丽华1,2, 陈浩如1,2, 王肇鼎1,2. 盐度对军曹鱼胚胎和仔鱼发育的影响[J]. , 2006, 25(1): 48-51.
SUN Li-hua1,2, CHEN Hao-ru1,2, WANG Zhao-ding1,2. Effect of salinity on embryonic and larval development of cobia(Rachycentron canadum). , 2006, 25(1): 48-51.
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