Effects of the amplitude(± 2, ± 4, ± 6, and ± 8) and frequency(2, 4, and 8 d) of salinity fluctuation on the body composition and energy budget of juvenile tongue sole(Cynoglossus semilaevis) were ...Effects of the amplitude(± 2, ± 4, ± 6, and ± 8) and frequency(2, 4, and 8 d) of salinity fluctuation on the body composition and energy budget of juvenile tongue sole(Cynoglossus semilaevis) were investigated in a 64-d experiment. Results showed that the amplitude and frequency of salinity fluctuation had significant interaction and both substantially affected the final weight and specific growth rate of juvenile tongue sole. The tongue sole exhibited better growth in treatments with moderate amplitude and frequency of salinity fluctuation(amplitude ± 4–6; frequency 4–8 d) than in other treatments and the control. In terms of energy budget, salinity fluctuation strongly affected the proportions of energy components, including those deposited for growth and lost in respiration, feces, and excretion. Moderately amplitude and frequency of salinity fluctuationg that favored the growth of tongue sole partitioned more energy for growth and less energy for metabolism than the constant and other amplitude and frequency of salinity fluctuation. Average energy budget for tongue sole at moderately fluctuating salinity was determined to be 100C(food) = 30.92G(growth) + 10.30F(feces) + 6.77U(excretion) + 52.01R(respiration). Energetic advantage at moderately fluctuating salinity, including increased energy intake, high assimilation efficiency, reduced metabolism expenditure, and more energy partitioned into growth, might account for the enhancement of tongue sole growth. Commercial farmers are recommended to rear juvenile tongue sole with moderate salinity fluctuations for better growth performance of this species.展开更多
A starvation trial was conducted to determine compensatory growth of the juvenile golden pompano Trachinotus ovatus which were deprived of food for 1, 2, 5 and 7 days respectively. The results of tests in outdoor ceme...A starvation trial was conducted to determine compensatory growth of the juvenile golden pompano Trachinotus ovatus which were deprived of food for 1, 2, 5 and 7 days respectively. The results of tests in outdoor cement pools and net pens showed that, in the first 15 days and 30 days, the growth of 1 day and 2 days-deprived groups was probably the same with that of control group, which accorded with fully compensatory description. However, the weight of 5 days and 7 days-deprived fingerlings were lower than that of the control group, which accorded with the description of the partial compensatory growth. As the starvation prolonged, feed conversion efficiency of the starved groups increased and was higher than the control group. Meanwhile, feeding rate also increased, but the fish of 1 day and 2 days-deprived groups was lower than that of the control group, and feeding quantity reduced and was lower than that of the control group. It suggested that the mechanism of compensatory growth was mainly due to improving feed conversion efficiency. Fish biochemical composition was analyzed： the water content and ash of fish sample increased due to starvation, while the lipid and protein decreased. The loss of lipid was greater than that of the protein, and the biochemical composition of fish in each group was restored to the control level by the end of the experiment. It suggested that Trachinotus ovatus may mainly consume lipid during the period of starvation.展开更多
Fish protein concentration(FPC)by alkaline solubilization has proven to be an alternative method in adding value to muscle-based materials.The aim of this work was to evaluate the influence of different processes(deca...Fish protein concentration(FPC)by alkaline solubilization has proven to be an alternative method in adding value to muscle-based materials.The aim of this work was to evaluate the influence of different processes(decanting/sieving or centrifugation),reagents(sodium bicarbonate or sodium hydroxide)and washing cycles(1–4)on the quality of protein concentrates obtained from mechanically separated meat(MSM)and viscera of hybrid sorubim(Pseudoplatystoma reticulatum×P.corruscans)and pacu(Piaractus mesopotamicus)fishes.The protein concentrate was obtained by washing the viscera or MSM during up to four cycles(4:1 solution:meat ratio).In each cycle,the liquid waste and fat were removed by decanting/sieving or centrifugation.Moisture,crude protein,crude fat and crude ash contents were determined after each washing cycle.The moisture and protein contents increased immediately after the first washing up to 77.88%(dry basis).The lipid content decreased with the cycles down to 2.99%(dry basis).Higher FPC yield was obtained for MSM during the centrifugation process compared to the decantation/sieving process.Two weight yields above 100%were found in procedures with NaHCO3 and MSM of hybrid sorubim and pacu,probably due to the larger capacity of gel formation during protein concentration.Differences related to the fish species were more evident than the processes and utilized reagents.展开更多
基金supported by the National Great Project of Scientific and Technical Supporting Programs of China (Grant No. 2011BAD13B03)]the Program for Excellent Youth Foundation of Shandong province (Grant No. JQ201009)the Public Science and Technology Research Funds Projects of Ocean, State Oceanic Administration of the People’s Republic of China (Grant No. 200905020)
文摘Effects of the amplitude(± 2, ± 4, ± 6, and ± 8) and frequency(2, 4, and 8 d) of salinity fluctuation on the body composition and energy budget of juvenile tongue sole(Cynoglossus semilaevis) were investigated in a 64-d experiment. Results showed that the amplitude and frequency of salinity fluctuation had significant interaction and both substantially affected the final weight and specific growth rate of juvenile tongue sole. The tongue sole exhibited better growth in treatments with moderate amplitude and frequency of salinity fluctuation(amplitude ± 4–6; frequency 4–8 d) than in other treatments and the control. In terms of energy budget, salinity fluctuation strongly affected the proportions of energy components, including those deposited for growth and lost in respiration, feces, and excretion. Moderately amplitude and frequency of salinity fluctuationg that favored the growth of tongue sole partitioned more energy for growth and less energy for metabolism than the constant and other amplitude and frequency of salinity fluctuation. Average energy budget for tongue sole at moderately fluctuating salinity was determined to be 100C(food) = 30.92G(growth) + 10.30F(feces) + 6.77U(excretion) + 52.01R(respiration). Energetic advantage at moderately fluctuating salinity, including increased energy intake, high assimilation efficiency, reduced metabolism expenditure, and more energy partitioned into growth, might account for the enhancement of tongue sole growth. Commercial farmers are recommended to rear juvenile tongue sole with moderate salinity fluctuations for better growth performance of this species.
基金Supported by Ocean Public Welfare Scientific Research Project,State Oceanic Administration of the People's Republic of China(Grant No.201205028)Key Projects in the National Science&Technology Pillar Program during the Twelfth Five-year Plan Period(2011BD13B11)Hainan Scientific Operating Expense Projects and Major Project of Science and Technology(ZDZX2013009,ZDZX2013014)
文摘A starvation trial was conducted to determine compensatory growth of the juvenile golden pompano Trachinotus ovatus which were deprived of food for 1, 2, 5 and 7 days respectively. The results of tests in outdoor cement pools and net pens showed that, in the first 15 days and 30 days, the growth of 1 day and 2 days-deprived groups was probably the same with that of control group, which accorded with fully compensatory description. However, the weight of 5 days and 7 days-deprived fingerlings were lower than that of the control group, which accorded with the description of the partial compensatory growth. As the starvation prolonged, feed conversion efficiency of the starved groups increased and was higher than the control group. Meanwhile, feeding rate also increased, but the fish of 1 day and 2 days-deprived groups was lower than that of the control group, and feeding quantity reduced and was lower than that of the control group. It suggested that the mechanism of compensatory growth was mainly due to improving feed conversion efficiency. Fish biochemical composition was analyzed： the water content and ash of fish sample increased due to starvation, while the lipid and protein decreased. The loss of lipid was greater than that of the protein, and the biochemical composition of fish in each group was restored to the control level by the end of the experiment. It suggested that Trachinotus ovatus may mainly consume lipid during the period of starvation.
文摘Fish protein concentration(FPC)by alkaline solubilization has proven to be an alternative method in adding value to muscle-based materials.The aim of this work was to evaluate the influence of different processes(decanting/sieving or centrifugation),reagents(sodium bicarbonate or sodium hydroxide)and washing cycles(1–4)on the quality of protein concentrates obtained from mechanically separated meat(MSM)and viscera of hybrid sorubim(Pseudoplatystoma reticulatum×P.corruscans)and pacu(Piaractus mesopotamicus)fishes.The protein concentrate was obtained by washing the viscera or MSM during up to four cycles(4:1 solution:meat ratio).In each cycle,the liquid waste and fat were removed by decanting/sieving or centrifugation.Moisture,crude protein,crude fat and crude ash contents were determined after each washing cycle.The moisture and protein contents increased immediately after the first washing up to 77.88%(dry basis).The lipid content decreased with the cycles down to 2.99%(dry basis).Higher FPC yield was obtained for MSM during the centrifugation process compared to the decantation/sieving process.Two weight yields above 100%were found in procedures with NaHCO3 and MSM of hybrid sorubim and pacu,probably due to the larger capacity of gel formation during protein concentration.Differences related to the fish species were more evident than the processes and utilized reagents.
