[Objective] The aim of this study was to study effects of metal ions on the protease activities in digestive tissues and gland of red-white ornamental carp（Cyprinus carpio L）.[Method] Effects of four kinds of metal ...[Objective] The aim of this study was to study effects of metal ions on the protease activities in digestive tissues and gland of red-white ornamental carp（Cyprinus carpio L）.[Method] Effects of four kinds of metal ions （K＋,Na＋,Mg2＋ and Ca2＋） on protease activities in hepatopancreas,foregut,midgut,hindgut of red-white ornamental carp were studied by enzyme analysis method.[Result] Effects of four kinds of metal ions on protease activities of red-white ornamental carp were different in the range of experimental concentration from 25 mmol/L to 150 mmol/L.K＋ could promote protease activities in hepatopancreas and hindgut at different levels.Especially,K＋ had the promoting effect at low-concentration level,but the inhibitory effect at high-concentration level in midgut and the inhibitory effect in foregut.Na＋ had the promoting effect on protease activities in hepatopancreas,foregut and hindgut at different levels,but the inhibitory effect in midgut.Mg2＋ and Ca2＋ had the inhibitory effect on protease activities in intestinal and hepatopancreas at different levels.[Conclusion] This study provides basic data and theoretical foundation for researches on the digestive physiology of red-white ornamental carp or the development and optimization of compound feed.展开更多
The essay studies the influence of the different intensities of fishing stress on body weight （7.30 ± 1.48） g of red crucian carp juvenile body length, weight, fatness, feeding rate, specific growth rate, food ...The essay studies the influence of the different intensities of fishing stress on body weight （7.30 ± 1.48） g of red crucian carp juvenile body length, weight, fatness, feeding rate, specific growth rate, food conversion rate, intestinal protease, amylase and immunoglobulin. The result showed that body length, weight, fatness, feeding rate, specific growth rate of red crucian carp juvenile were significantly inhibited from fishing stress compared with the control group, and the magnitude of the inhibitory effect increased with the time going and increased. Fishing stress could increase the food conversion rate of red crucian carp juvenile, and the different intensity stress had no significant different influence. The intestinal protease activity decreased in the beginning, then increased, and was consistent with the level of the control group ultimately. High-stress group accelerated the decline of intestinal amylase activity of the juvenile. The stress increased the number of immunoglobulin of juvenile red crucian carp significantly, but the increase disappeard with the stress time extended.展开更多
The aim of the present study was to develop a formulated feed for improving skin pigmentation and growth performance of koi carp juveniles. Two experiments were conducted for determination of an optimal dietary astaxa...The aim of the present study was to develop a formulated feed for improving skin pigmentation and growth performance of koi carp juveniles. Two experiments were conducted for determination of an optimal dietary astaxanthin and FM （fish meal） ration for koi carp juveniles. In the first experiment, three isonitrogenous and isoenergetic dietary treatments were designed with three different levels of astaxanthin consisted of 60, 80 and 100 mg/kg and a commercial feed served as a control. For the second experiment, four isonitrogenous and isoenergetic dietary treatments were formulated with graded inclusions of dietary FM replaced from 0% to 60% at 20% increments by SM （soybean meal）, PBM （poultry by-product meal）, and a CD （control diet）. Obtained results demonstrated that skin pigmentation of koi carp juveniles fed the diet containing 80 mg/kg astaxanthin, 36.02% protein, 7.78% lipid, 4.20 Kcal/g GE （gross energy） were more better than those at the diet with lower estaxanthin content and commercial diet. Moreover, the highest growth and feed utilization of fish were observed at this diet with WG （weight gain）, SGR （specific growth rate） and FCR （feed conversion ratio） were 121.80%, 0.95 （%/day） and 1.6, respectively.展开更多
Laboratory experiments were conducted to determine the effects of total dissolved gas （TDG） supersaturation on acute lethality and avoidance responses in juvenile rock carp （Procypris rabaudi Tchang）. The juvenile...Laboratory experiments were conducted to determine the effects of total dissolved gas （TDG） supersaturation on acute lethality and avoidance responses in juvenile rock carp （Procypris rabaudi Tchang）. The juvenile rock carp were exposed to water with different levels of supersaturation （105%, 115%, 120%, 125%, 130%, 135%, 140%, and 145%） and depth of 0.20 m at 25℃ for 60 h. Median lethal time （LT50） was used to assess the lethal responses corresponding to different levels of gas supersaturation. The results show that half of the juvenile rock carp died at the 120%, 125%, 130%, 135%, 140%, and 145% levels of supersaturation, and the LT50 corresponding to different levels of supersaturation was 18.7, 15.4, 8.2, 6.6, 3.5, and 1.7 h. When the level of supersaturated water is below 115%, the mortality is negligible. Avoidance responses were observed 5 min after the fish were put into equilibrated water （99%, 0.08 m deep） and water with different supersaturated levels （105%, 115%, 125%, 135%, and 145%, 0.08 m deep） at 25 ℃. The fish exhibited strong avoidance responses in supersaturated water when the gas supersaturation was above 135%. However, they exhibited an obvious preference to supersaturated water when the gas supersaturation was below 115%. Thus, the juvenile rock carp can likely survive in water with a supersaturated level of 115%.展开更多
Fishes exposed to different dissolved oxygen concentrations over prolonged time periods have different susceptibility and adaptation mechanisms.In this study,healthy grass carp with an average weight of 214.6±18....Fishes exposed to different dissolved oxygen concentrations over prolonged time periods have different susceptibility and adaptation mechanisms.In this study,healthy grass carp with an average weight of 214.6±18.7 g were selected for long-term culture in recirculating aquaculture systems at three different dissolved oxygen concentrations,i.e.,3.00 mg/L[(2.57±0.33)mg/L,DO_(2.57)),5.00 mg/L[(4.61±0.11)mg/L,DO_(4.61)],which was the control group,and 7.00 mg/L[(6.50±0.48)mg/L,DO_(6.50)].Blood,gill,muscle,and liver samples were collected after 60 days.Using hematoxylin-eosin(HE),alcian blue periodic acid Schiff(AB-PAS)staining,determination of respiratory metabolism enzyme activity,and fluorescent quantitative PCR,the adaptability of juvenile grass carp facing different dissolved oxygen levels were explored.The results showed that the respiration rate increased,and hemoconcentration and hemoglobin(Hb),electrolyte and pH changed at DO2.57.Furthermore,gill lamellae became thinner and longer,the distance between them increased,the mucus on them decreased and the interstitial cell mass decreased.In addition,the relative expression of apoptosis-related genes bcl-2 and bcl-xl in gill tissue decreased,while caspase-3 and bax increased.In muscles and liver tissues,lactate dehydrogenase(LDH)activity and lactic acid content(LA)increased,pyruvate dehydrogenase(PDH)activity decreased,and genes related to the respiratory metabolic enzymes PDH-A4 and PDH-E1α also changed accordingly.The oxygen consumption rate decreased significantly(P<0.05).At DO_(6.50),the distance between gill lamellae,numbers of red blood cells(RBC)and the content of hemoglobin decreased wheras the mucus on gill lamellae increased.The activity of PDH,the expression of PDH-E1a in liver and oxygen consumption rate increased.Different dissolved oxygen concentrations affected the respiratory behavior,gill tissue structure,blood transport capacity and tissue enzyme activity of juvenile grass carp.In summary,juvenile grass carp showed different adaptation strategies when facing different dissolved oxygen concentrations over prolonged periods in recirculating aquaculture systems.展开更多
文摘[Objective] The aim of this study was to study effects of metal ions on the protease activities in digestive tissues and gland of red-white ornamental carp（Cyprinus carpio L）.[Method] Effects of four kinds of metal ions （K＋,Na＋,Mg2＋ and Ca2＋） on protease activities in hepatopancreas,foregut,midgut,hindgut of red-white ornamental carp were studied by enzyme analysis method.[Result] Effects of four kinds of metal ions on protease activities of red-white ornamental carp were different in the range of experimental concentration from 25 mmol/L to 150 mmol/L.K＋ could promote protease activities in hepatopancreas and hindgut at different levels.Especially,K＋ had the promoting effect at low-concentration level,but the inhibitory effect at high-concentration level in midgut and the inhibitory effect in foregut.Na＋ had the promoting effect on protease activities in hepatopancreas,foregut and hindgut at different levels,but the inhibitory effect in midgut.Mg2＋ and Ca2＋ had the inhibitory effect on protease activities in intestinal and hepatopancreas at different levels.[Conclusion] This study provides basic data and theoretical foundation for researches on the digestive physiology of red-white ornamental carp or the development and optimization of compound feed.
文摘The essay studies the influence of the different intensities of fishing stress on body weight （7.30 ± 1.48） g of red crucian carp juvenile body length, weight, fatness, feeding rate, specific growth rate, food conversion rate, intestinal protease, amylase and immunoglobulin. The result showed that body length, weight, fatness, feeding rate, specific growth rate of red crucian carp juvenile were significantly inhibited from fishing stress compared with the control group, and the magnitude of the inhibitory effect increased with the time going and increased. Fishing stress could increase the food conversion rate of red crucian carp juvenile, and the different intensity stress had no significant different influence. The intestinal protease activity decreased in the beginning, then increased, and was consistent with the level of the control group ultimately. High-stress group accelerated the decline of intestinal amylase activity of the juvenile. The stress increased the number of immunoglobulin of juvenile red crucian carp significantly, but the increase disappeard with the stress time extended.
文摘The aim of the present study was to develop a formulated feed for improving skin pigmentation and growth performance of koi carp juveniles. Two experiments were conducted for determination of an optimal dietary astaxanthin and FM （fish meal） ration for koi carp juveniles. In the first experiment, three isonitrogenous and isoenergetic dietary treatments were designed with three different levels of astaxanthin consisted of 60, 80 and 100 mg/kg and a commercial feed served as a control. For the second experiment, four isonitrogenous and isoenergetic dietary treatments were formulated with graded inclusions of dietary FM replaced from 0% to 60% at 20% increments by SM （soybean meal）, PBM （poultry by-product meal）, and a CD （control diet）. Obtained results demonstrated that skin pigmentation of koi carp juveniles fed the diet containing 80 mg/kg astaxanthin, 36.02% protein, 7.78% lipid, 4.20 Kcal/g GE （gross energy） were more better than those at the diet with lower estaxanthin content and commercial diet. Moreover, the highest growth and feed utilization of fish were observed at this diet with WG （weight gain）, SGR （specific growth rate） and FCR （feed conversion ratio） were 121.80%, 0.95 （%/day） and 1.6, respectively.
基金Project (No. 50979063) supported by the National Natural Science Foundation of China
文摘Laboratory experiments were conducted to determine the effects of total dissolved gas （TDG） supersaturation on acute lethality and avoidance responses in juvenile rock carp （Procypris rabaudi Tchang）. The juvenile rock carp were exposed to water with different levels of supersaturation （105%, 115%, 120%, 125%, 130%, 135%, 140%, and 145%） and depth of 0.20 m at 25℃ for 60 h. Median lethal time （LT50） was used to assess the lethal responses corresponding to different levels of gas supersaturation. The results show that half of the juvenile rock carp died at the 120%, 125%, 130%, 135%, 140%, and 145% levels of supersaturation, and the LT50 corresponding to different levels of supersaturation was 18.7, 15.4, 8.2, 6.6, 3.5, and 1.7 h. When the level of supersaturated water is below 115%, the mortality is negligible. Avoidance responses were observed 5 min after the fish were put into equilibrated water （99%, 0.08 m deep） and water with different supersaturated levels （105%, 115%, 125%, 135%, and 145%, 0.08 m deep） at 25 ℃. The fish exhibited strong avoidance responses in supersaturated water when the gas supersaturation was above 135%. However, they exhibited an obvious preference to supersaturated water when the gas supersaturation was below 115%. Thus, the juvenile rock carp can likely survive in water with a supersaturated level of 115%.
基金supported by the earmarked fund for CARS(CARS-45)the Fundamental Research Funds for the Central Universities(No.2662022SCYJ001)the National Key R&D Program of China(No.2019YFD0900303).
文摘Fishes exposed to different dissolved oxygen concentrations over prolonged time periods have different susceptibility and adaptation mechanisms.In this study,healthy grass carp with an average weight of 214.6±18.7 g were selected for long-term culture in recirculating aquaculture systems at three different dissolved oxygen concentrations,i.e.,3.00 mg/L[(2.57±0.33)mg/L,DO_(2.57)),5.00 mg/L[(4.61±0.11)mg/L,DO_(4.61)],which was the control group,and 7.00 mg/L[(6.50±0.48)mg/L,DO_(6.50)].Blood,gill,muscle,and liver samples were collected after 60 days.Using hematoxylin-eosin(HE),alcian blue periodic acid Schiff(AB-PAS)staining,determination of respiratory metabolism enzyme activity,and fluorescent quantitative PCR,the adaptability of juvenile grass carp facing different dissolved oxygen levels were explored.The results showed that the respiration rate increased,and hemoconcentration and hemoglobin(Hb),electrolyte and pH changed at DO2.57.Furthermore,gill lamellae became thinner and longer,the distance between them increased,the mucus on them decreased and the interstitial cell mass decreased.In addition,the relative expression of apoptosis-related genes bcl-2 and bcl-xl in gill tissue decreased,while caspase-3 and bax increased.In muscles and liver tissues,lactate dehydrogenase(LDH)activity and lactic acid content(LA)increased,pyruvate dehydrogenase(PDH)activity decreased,and genes related to the respiratory metabolic enzymes PDH-A4 and PDH-E1α also changed accordingly.The oxygen consumption rate decreased significantly(P<0.05).At DO_(6.50),the distance between gill lamellae,numbers of red blood cells(RBC)and the content of hemoglobin decreased wheras the mucus on gill lamellae increased.The activity of PDH,the expression of PDH-E1a in liver and oxygen consumption rate increased.Different dissolved oxygen concentrations affected the respiratory behavior,gill tissue structure,blood transport capacity and tissue enzyme activity of juvenile grass carp.In summary,juvenile grass carp showed different adaptation strategies when facing different dissolved oxygen concentrations over prolonged periods in recirculating aquaculture systems.
基金National Key Technologies R&D Programfor the11th Five-year Plan of China (2006BAD03B03)the Open Program of the Key Laboratory of Freshwater Ecology & Healthy Aquaculture,Chinese Academy of Fishery Sciences (2007FE0209)
