A factorial study was conducted to determine the effects of salinity （constant （SO） and fluctuating （S10）） and isoenergetic diet of different protein/carbohydrate ratios （P/C： 4.1, 1.9, 1.0 and 0.6） on the su...A factorial study was conducted to determine the effects of salinity （constant （SO） and fluctuating （S10）） and isoenergetic diet of different protein/carbohydrate ratios （P/C： 4.1, 1.9, 1.0 and 0.6） on the survival and growth of juvenile Litopenaeus vannamei. The experiment lasted for 35 days. The results showed that I） At S0 and S10, specific growth rate and apparent digestibility coefficient exhibited decreasing trend, while food conversion ratio exhibited increasing trend, with decreasing P/C ratio. At SO, food consumption and specific growth rate of the shrimp fed 4.1 P/C were significantly higher than those fed 1.0 and 0.6 P/C, whereas at S10, no significant differences were detected among different treatments; II） At 4.1 and 1.9 P/C, food consumption and specific growth rate were higher in the shrimp maintained at SO as compared with those at S10, while at 1.0 and 0.6 P/C, an inverse trend was observed. Among four P/C ratios, food conversion ratio of the shrimp at SO was the lowest.展开更多
The effects of various salinity fluctuation amplitudes （2, 4, 6 and 8） on the growth, osmolarity, Na＋-K＋-ATPase activity and Hsp70 of juvenile Fenneropenaeus chinensis cultured in seawater with a salinity of 20 we...The effects of various salinity fluctuation amplitudes （2, 4, 6 and 8） on the growth, osmolarity, Na＋-K＋-ATPase activity and Hsp70 of juvenile Fenneropenaeus chinensis cultured in seawater with a salinity of 20 were studied. The results show that weight gain in the salinity fluctuation treatments was better than that in control; in particular, the weight gain of treatments S4 and SO, at 231.8% and 196.3%, respectively, was significantly different （P〈0.05）. The hemolymph osmolarity of treatments SO, S2, S4, S6 and S8 was 635.4, 630.8, 623.6, 614.4 and 600.3 mOsm/kg, respectively, and decreased with increasing salinity fluctuation amplitude. The level of Na＋-K＋-ATPase activity in gills ofE chinensis was higher than that in hepatopancreas, but there were no significant differences among all treatments, either in gills or hepatopancreas （P〉0.05）. The relative level of Hsp70 in treatment $4 was 48.4% and 40.4% higher than control in muscle and eyestalks, respectively, with the highest values being recorded under a salinity fluctuation amplitude of 4.展开更多
基金funded by National Key Project of Scientific and Technical Supporting Programs funded by Ministry of Science & Technology of China (Grant No. 2006BAD09A01, 2006BAD09A06)Jiangsu Provincial Science Foundation for Talent Youths (Grant No. 2006548) Open Fund of Jiangsu Key Laboratory of Marine Biotechnology (Grant No. 2006HS017)
文摘A factorial study was conducted to determine the effects of salinity （constant （SO） and fluctuating （S10）） and isoenergetic diet of different protein/carbohydrate ratios （P/C： 4.1, 1.9, 1.0 and 0.6） on the survival and growth of juvenile Litopenaeus vannamei. The experiment lasted for 35 days. The results showed that I） At S0 and S10, specific growth rate and apparent digestibility coefficient exhibited decreasing trend, while food conversion ratio exhibited increasing trend, with decreasing P/C ratio. At SO, food consumption and specific growth rate of the shrimp fed 4.1 P/C were significantly higher than those fed 1.0 and 0.6 P/C, whereas at S10, no significant differences were detected among different treatments; II） At 4.1 and 1.9 P/C, food consumption and specific growth rate were higher in the shrimp maintained at SO as compared with those at S10, while at 1.0 and 0.6 P/C, an inverse trend was observed. Among four P/C ratios, food conversion ratio of the shrimp at SO was the lowest.
基金Supported by the National Natural Science Foundation of China (No. 30571441)Reward Research Foundation for Talented Young and Middle Aged Scientists of Shandong,China (No. 2006BS07002)National Key Technology Research and Development Program of China (No. 2006BAD09A07)
文摘The effects of various salinity fluctuation amplitudes （2, 4, 6 and 8） on the growth, osmolarity, Na＋-K＋-ATPase activity and Hsp70 of juvenile Fenneropenaeus chinensis cultured in seawater with a salinity of 20 were studied. The results show that weight gain in the salinity fluctuation treatments was better than that in control; in particular, the weight gain of treatments S4 and SO, at 231.8% and 196.3%, respectively, was significantly different （P〈0.05）. The hemolymph osmolarity of treatments SO, S2, S4, S6 and S8 was 635.4, 630.8, 623.6, 614.4 and 600.3 mOsm/kg, respectively, and decreased with increasing salinity fluctuation amplitude. The level of Na＋-K＋-ATPase activity in gills ofE chinensis was higher than that in hepatopancreas, but there were no significant differences among all treatments, either in gills or hepatopancreas （P〉0.05）. The relative level of Hsp70 in treatment $4 was 48.4% and 40.4% higher than control in muscle and eyestalks, respectively, with the highest values being recorded under a salinity fluctuation amplitude of 4.
