| Centropristis striata ,which is generally called Black seabass, is a newly introduced specise from American.For it's high edibl proportation and it's acclimation to northern China climate,it maybe a new specise for culturing in China.This thesis includes the following four parts: The Influence of Temperature on the Growth and Energy Budget of Centropristis striata;Responses of Superoxide Dismutase,Catalyse and Reduced Glutathione Antioxidant Defenses in Gill of Centropristis striata to Short Term Elevated Temperature;Effects of Salinity on Plasma Osmolality and Gill Na+-K+-ATPase Activity of Centropristis striata ;The Effect of Salinity on Growth and Energy Budget of Centropristis striata ; the main results show as follows:1. The Influence of Temperature on the Growth and Energy Budget of Centropristis striataIn the laboratory,under the condition of flowing water, we studied the growth,chemical composition and energy budget of the Centropristis striata, we designed four different water temperature:9,13,17,21℃,each treatment had three replicates. The result showed: at 9℃, RSG was minus , the growth energy was -281.1±20.8 kJ,at 13℃the growth energy was 127.6±8.1 kJ.So the compensation temperature was between 9～13℃.21℃was still a suitable temperature for Centropristis striata to grow.Respiration energy and growth energy dominated the energy allocation pattern. There was no obvious relationship between water temperature and the content of water and ash of the experimental fish ,but water temperature had significant effect on the content of protein(P<0.05),in the term of lipid, 9℃>21℃>17℃>13℃.2.Responses of Superoxide Dismutase,Catalyse and Reduced Glutathione Antioxidant Defenses in Gill of Centropristis striata to Short Term Elevated Temperature.In this experiment,we set three temperature treatments: 25℃,28℃and 31℃.The temperature was abruptly changed. In order to understand how the antioxidative enzymes changed under heat stress,we collected fish gill from 1h to 4h, the results showed that the SOD activity increased significantly(P<0.05) in comparision to the control.At 28℃, the difference between 2h and 4h was non-signficant(P<0.05). At 31℃, the differences between 3h and 4h was non-signficant(P<0.05).In the term of CAT activity,1~ 2h, the difference between 28℃and 31℃was non-signficant(P>0.05).After 3 hours ,the difference between the experimental groups and the control was significant(P<0.05).The content of GSH decreased significantly(P<0.05)with the elevated temperature. 1~4h,the difference between experimental groups and the control was significant(P<0.05).At 28℃,the differences between 1h and 2h was non-signficant. At 31℃,the differences between 3h and 4h was non-signficant(P>0.05).3.The Effect of Salinity on Growth and Energy Budget of Centropristis striataIn the lab,we studied the growth and energy budget of Centropristis striata under different salinity .The water temperature was set on 21℃,we designed four salinity treatments: 9,16,23,30,each treatment had four replicates.The results showed that salinity had significant effect on FCR and SGR(P<0.05),both of them reached peak value at 16, they were 1.42(%/d) and 19.59%,respectively.At 16,the ratio of growth energy to food energy and respiratory energy to food energy were 28.22%and 59.09%.The salinity didn't show significant effect on the content of protein,lipid and ash(P>0.05).4.Effects of Salinity on Plasma Osmolality and Gill Na+-K+-ATPase Activity of Centropristis striataPlasma osmolality and gill Na+-K+-ATPase activity of juveniles Cetropristis striata were studied in enzymology analysis at an abrupt change of salinity from 30 to 23,16 and 9.The weight and body length of Centropristis Striata were 12.48±3.21g and 7.34±1.31cm.Since the beginning of the experiment ,samples were taken at 0h﹑12h﹑1d﹑3d﹑6d﹑9d﹑12d.The results of the experiment showed that the effect of salinity on plasma osmolality and gill Na+-K+-ATPase activity of the fish was significant different(P<0.05).In the term of plasma osmolality ,on the third day,the plasma osmolality value dropped to the lowest,while on the ninth day,all experimental groups resumed to it,s origina level; gill Na+-K+-ATPase showed the same trend as plasma osmolality,but gill Na+-K+-ATPase activity dropped to it,s lowest value on the sixth day and on the twelth day, groups of salinity 9 and 16 are still lower than their original level.The bigger drop of salinity ,the more obvious declination of blood osmolality and gill Na+-K+-ATPase activity.
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