In two penaeid shrimp (Penaeus monodon and Penaeus penicillatus)postlarvae exposed to 10, 50, 500μg/L Cu, Cd and CuLCd(1:1) mixture respectively,the total carbohydrate(CHO), ash, lipid and moisturegradually decreased...In two penaeid shrimp (Penaeus monodon and Penaeus penicillatus)postlarvae exposed to 10, 50, 500μg/L Cu, Cd and CuLCd(1:1) mixture respectively,the total carbohydrate(CHO), ash, lipid and moisturegradually decreased to a little less than that in the controls without exposure to the twe metals asconcentration increased; but the protein amount gradually increased to a little above that in the controls.Cu caused more reduction in CHO, ash, and lipid as compared to Cd. In contrast, reduction in total constituents was not notable in the case of exposure. to 1:1 mixture of both metals.There were negligiblechanges in all components at 10 μg/L exposure of each metal. Cu, like Zn, probably induced synthesis of specific metal binding proteins (metallothionine) causing increase in synthesis of proteins.In mixture,Cd had antagonistic effects on total composition of constituents in postlarvae.展开更多
Studies of dynamics in Albatross Bay, the Gulf of Carpentaria, Australia, show strong tides of which M<sub>2</sub>is the dominant constituent in the region. Tidal fronts are present and they can be modeled...Studies of dynamics in Albatross Bay, the Gulf of Carpentaria, Australia, show strong tides of which M<sub>2</sub>is the dominant constituent in the region. Tidal fronts are present and they can be modeled by a 2-Dtidal model. Density currents have also been observed with seasonal variations due to the influence ofwet or dry seasons. This paper reviews the effects of these dynamics on the migration of prawn postlarvae in AlbatrossBay and its estuaries. It is found that through its vertical movement triggered by change of salinity theprawn postlarvae can be transported from the coast to the estuary by tides within 2.8 weeks. Howeverthis horizontal displacement mechanism may be destroyed by the tidal front in Albatross Bay. Densitycurrents may alter prawn postlarvae positions in Albatross Bay on a seasonal scale.展开更多
A 3 x 4 two-factor factorial experimental design with three replications per treatment was conducted to determine the effects three temperatures viz., room temperature (29°C ± 1°C) and elevated temperat...A 3 x 4 two-factor factorial experimental design with three replications per treatment was conducted to determine the effects three temperatures viz., room temperature (29°C ± 1°C) and elevated temperatures (33°C and 35°C ± 0.5°C) and four salinities (25, 30, 33 and 35 ppt) on survival of postlarvae tiger prawn Penaeus monodon under laboratory conditions. Results showed that temperature had a greater influence on survival of postlarvae P. monodon than salinity and low water temperature (29°C) gave better larval survival than higher water temperatures (33°C and 35°C). In addition, the PL1 had better tolerance to high temperatures than PL15. At the termination of the experiment, the best survival of PL1 was found at 29°C for all salinities tested with an average of 95.8%, while the best survival of PL15 was also found at 29°C for all salinities tested with an average of 70.6%. Based on survival at temperatures and salinities tested, the best salinity and temperature combination for the culture of P. monodon PL1 and PL15 were 29°C at 25, 30, 33 and 35 ppt, and 29°C at 25 and 30 ppt, respectively.展开更多
文摘In two penaeid shrimp (Penaeus monodon and Penaeus penicillatus)postlarvae exposed to 10, 50, 500μg/L Cu, Cd and CuLCd(1:1) mixture respectively,the total carbohydrate(CHO), ash, lipid and moisturegradually decreased to a little less than that in the controls without exposure to the twe metals asconcentration increased; but the protein amount gradually increased to a little above that in the controls.Cu caused more reduction in CHO, ash, and lipid as compared to Cd. In contrast, reduction in total constituents was not notable in the case of exposure. to 1:1 mixture of both metals.There were negligiblechanges in all components at 10 μg/L exposure of each metal. Cu, like Zn, probably induced synthesis of specific metal binding proteins (metallothionine) causing increase in synthesis of proteins.In mixture,Cd had antagonistic effects on total composition of constituents in postlarvae.
文摘Studies of dynamics in Albatross Bay, the Gulf of Carpentaria, Australia, show strong tides of which M<sub>2</sub>is the dominant constituent in the region. Tidal fronts are present and they can be modeled by a 2-Dtidal model. Density currents have also been observed with seasonal variations due to the influence ofwet or dry seasons. This paper reviews the effects of these dynamics on the migration of prawn postlarvae in AlbatrossBay and its estuaries. It is found that through its vertical movement triggered by change of salinity theprawn postlarvae can be transported from the coast to the estuary by tides within 2.8 weeks. Howeverthis horizontal displacement mechanism may be destroyed by the tidal front in Albatross Bay. Densitycurrents may alter prawn postlarvae positions in Albatross Bay on a seasonal scale.
文摘A 3 x 4 two-factor factorial experimental design with three replications per treatment was conducted to determine the effects three temperatures viz., room temperature (29°C ± 1°C) and elevated temperatures (33°C and 35°C ± 0.5°C) and four salinities (25, 30, 33 and 35 ppt) on survival of postlarvae tiger prawn Penaeus monodon under laboratory conditions. Results showed that temperature had a greater influence on survival of postlarvae P. monodon than salinity and low water temperature (29°C) gave better larval survival than higher water temperatures (33°C and 35°C). In addition, the PL1 had better tolerance to high temperatures than PL15. At the termination of the experiment, the best survival of PL1 was found at 29°C for all salinities tested with an average of 95.8%, while the best survival of PL15 was also found at 29°C for all salinities tested with an average of 70.6%. Based on survival at temperatures and salinities tested, the best salinity and temperature combination for the culture of P. monodon PL1 and PL15 were 29°C at 25, 30, 33 and 35 ppt, and 29°C at 25 and 30 ppt, respectively.
