Information of the difference in quality between farmed and wild fish is central to better ensuring fish products produced in aquaculture meet regulatory and consumer requirements. Proximate composition, amino acid an...Information of the difference in quality between farmed and wild fish is central to better ensuring fish products produced in aquaculture meet regulatory and consumer requirements. Proximate composition, amino acid and fatty acid profiles, and toxic elements contents of fanned and wild Chanodichthys mongolicus were established and compared. Significantly higher crude protein content while lower moisture content in farmed fish compared to wild fish were observed （P〈0.05）. The percentages of total amino acids （TAA）, total essential amino acids （TEAA）, total non-essential amino acids （TNEAA） and total delicious amino acids （TDAA） in farmed fish were all significantly higher than those in the wild equivalent （P〈0.05）. Compared to the FAO/WHO recommended reference values, the ratios of TEAA/ TAA （39.84%o-40.33%） were comparable to 40% and TEAA / TNEAA （66.22%-67.60%） were above 60%. Fatty acid profiles in both farmed and wild C. mongolicus were dominated by monounsaturated fatty acid （MUFA）, with farmed fish contained much more MUFA content compared to wild counterpart （P〈0.05）. Notably, wild fish exhibited significantly higher levels of total polyunsaturated fatty acid （PUFA） including eicosapentaenoic acid （EPA） and docosahexaenoic acid （DHA） than fanned fish （P〈0.05）. The EPA （C20：503） and linoleic acid （C18：206） were the predominant PUFA in wild and farmed C. mongolicus, respectively. Moreover, farmed fish displayed an overall lower toxic element levels （As, Cd, Pb and Hg） in comparison with wild fish, and both were far lower than the established limit standard. In conclusion, our results suggest that the nutritional quality of fanned C. mongolicus was inferior to their wild counterpart with respect to fatty acids nutrition, and therefore further studies should focus on the improving C. mongolicus diet in order to enhance the overall nutritional composition.展开更多
Knowledge of oxygen consumption rates and asphyxiation points in fish is important to determine appropriate stocking and water quality management in aquaculture. The oxygen consumption rate and asphyxiation point in C...Knowledge of oxygen consumption rates and asphyxiation points in fish is important to determine appropriate stocking and water quality management in aquaculture. The oxygen consumption rate and asphyxiation point in Chanodichthys mongolicus were detected under laboratory conditions using an improved respirometer chamber. The results revealed that more accurate estimates can be obtained by adjusting the volume of the respirometer chamber, which may avoid system errors caused by either repeatedly adjusting fish density or selecting different equipment specifications. The oxygen consumption rate and asphyxiation point of C. mongolicus increased with increasing water temperature and decreasing fish size. Changes in the C. mongolicus oxygen consumption rate were divided into three stages at water temperatures of 11-33~C： （I） a low temperature oxygen consumption rate stage when water temperature was 11-19~C, （2） the optimum temperature oxygen consumption rate stage when water temperature was 19-23~C, and （3） a high temperature oxygen consumption rate stage when water temperature was 〉27~C. The temperature quotients （Q10） obtained suggested that C. mongolicus preferred a temperature range of 19-23~C. At 19~C, C. mongolicus exhibited higher oxygen consumption rates during the day when the maximum values were observed at 10：00 and 14：00 than at night when the minimum occurred at 02：00.展开更多
基金Supported by the Central-level Non-profit Scientific Research Institutes Special Funds(No.2014A07XK04)
文摘Information of the difference in quality between farmed and wild fish is central to better ensuring fish products produced in aquaculture meet regulatory and consumer requirements. Proximate composition, amino acid and fatty acid profiles, and toxic elements contents of fanned and wild Chanodichthys mongolicus were established and compared. Significantly higher crude protein content while lower moisture content in farmed fish compared to wild fish were observed （P〈0.05）. The percentages of total amino acids （TAA）, total essential amino acids （TEAA）, total non-essential amino acids （TNEAA） and total delicious amino acids （TDAA） in farmed fish were all significantly higher than those in the wild equivalent （P〈0.05）. Compared to the FAO/WHO recommended reference values, the ratios of TEAA/ TAA （39.84%o-40.33%） were comparable to 40% and TEAA / TNEAA （66.22%-67.60%） were above 60%. Fatty acid profiles in both farmed and wild C. mongolicus were dominated by monounsaturated fatty acid （MUFA）, with farmed fish contained much more MUFA content compared to wild counterpart （P〈0.05）. Notably, wild fish exhibited significantly higher levels of total polyunsaturated fatty acid （PUFA） including eicosapentaenoic acid （EPA） and docosahexaenoic acid （DHA） than fanned fish （P〈0.05）. The EPA （C20：503） and linoleic acid （C18：206） were the predominant PUFA in wild and farmed C. mongolicus, respectively. Moreover, farmed fish displayed an overall lower toxic element levels （As, Cd, Pb and Hg） in comparison with wild fish, and both were far lower than the established limit standard. In conclusion, our results suggest that the nutritional quality of fanned C. mongolicus was inferior to their wild counterpart with respect to fatty acids nutrition, and therefore further studies should focus on the improving C. mongolicus diet in order to enhance the overall nutritional composition.
基金Supported by the Central-Level Non-Profit Scientific Research Institutes Special Funds(Nos.2014A07XK04,HSY201403)the Harbin Science and Technology Project(No.2012AA6CN037)the National Key Technology Research and Development Program of China(No.2012BAD25B09)
文摘Knowledge of oxygen consumption rates and asphyxiation points in fish is important to determine appropriate stocking and water quality management in aquaculture. The oxygen consumption rate and asphyxiation point in Chanodichthys mongolicus were detected under laboratory conditions using an improved respirometer chamber. The results revealed that more accurate estimates can be obtained by adjusting the volume of the respirometer chamber, which may avoid system errors caused by either repeatedly adjusting fish density or selecting different equipment specifications. The oxygen consumption rate and asphyxiation point of C. mongolicus increased with increasing water temperature and decreasing fish size. Changes in the C. mongolicus oxygen consumption rate were divided into three stages at water temperatures of 11-33~C： （I） a low temperature oxygen consumption rate stage when water temperature was 11-19~C, （2） the optimum temperature oxygen consumption rate stage when water temperature was 19-23~C, and （3） a high temperature oxygen consumption rate stage when water temperature was 〉27~C. The temperature quotients （Q10） obtained suggested that C. mongolicus preferred a temperature range of 19-23~C. At 19~C, C. mongolicus exhibited higher oxygen consumption rates during the day when the maximum values were observed at 10：00 and 14：00 than at night when the minimum occurred at 02：00.
