The objective of the study was to explore the effect of acute low temperature stress on VO2 and Vf of Silurus meridionalis and Pelteobag vachelli after 10 minutes cold water bath with different temperature.The investi...The objective of the study was to explore the effect of acute low temperature stress on VO2 and Vf of Silurus meridionalis and Pelteobag vachelli after 10 minutes cold water bath with different temperature.The investigation was operated under the temperature of 24 ℃.It was found that the VO2 and Vf of Silurus meridionalis after 6 and 0 ℃ stress showed a decrease-increase-decrease trend while other groups showed a rapid increase then slowly recovery trend.The VO2 and Vf of Pelteobag vachelli after 0 ℃stress showed a decrease-increase-decrease trend while other groups showed an increase then slowly recovery process.It was suggested that Pelteobag vachelli was more adaptive to acute cold stress,but it cost more energy adapting to cold stress compared to Silurus meridionalis.展开更多
The routine metabolic rate in southern catfish juvenile(24.3-250.8 g)fed with saccharine feed(CHO)was measured in this study.Fish were fed with iso-nitrogenous(40 % crude protein)and iso-lipidic(10% crude lipid)experi...The routine metabolic rate in southern catfish juvenile(24.3-250.8 g)fed with saccharine feed(CHO)was measured in this study.Fish were fed with iso-nitrogenous(40 % crude protein)and iso-lipidic(10% crude lipid)experimental feed containing 0(control feed),15%,30% of carbohydrate level.The routine metabolic rates of 15 % and 30% dietary carbohydrate group were significantly higher than that of 0% dietary carbohydrate group.The relationship between body mass(Wt)and routine metabolic rate(Rr)of southern catfishfed with different test feed could be described as:(1)0% CHO:ln(Rr)=0.986 ln(Wt)+1.419 r2=0.922,n=25,P<0.001;(2)15% CHO:ln(Rr)=0.912 ln(Wt)+1.741 r2=0.966,n=21,P<0.001;(3)30% CHO:ln(Rr)=0.762 ln(Wt)+2.378 r2=0.958,n=21,P<0.001.The intercept was increased and mass coefficient was decreased with the increase of carbohydrate level in feed.It could be concluded that southern Silurus meridionalis had poor metabolic capacity which led the increase of routine metabolic rate of fish with small size.But with the increase of body size southern Silurus meridionalis might had a better adaptation to high carbohydrate concentration.展开更多
The large-scale green tide caused by Ulva has occurred successively in the Yellow Sea since 2007,and new events of green tide also continued to appear in nearby sea areas,indicating an undergoing rapid development of ...The large-scale green tide caused by Ulva has occurred successively in the Yellow Sea since 2007,and new events of green tide also continued to appear in nearby sea areas,indicating an undergoing rapid development of occurrence patterns for harmful macroalgal blooms(HMBs)along coastal China.In August 2021,a green tide occurred for the first time in Bayuquan sea area of Yingkou city,Liaoning Province in the Bohai Sea.In this study,morphological and molecular approaches were used to identify the causative species as U.meridionalis,an alien subtropical alga previously found to dominate green tides in the South China Sea.According to the hydrological data of Bayuquan in summer 2021,combined with morphological and developmental observations for this alga,we hypothesized that the disturbance caused by the typhoon In-Fa might have detached the local U.meridionalis from substrates,especially for those thalli with poorly developed holdfasts,and the ensuing wave-free period with unusually high temperature,which fell in the reported optimum growth temperature for U.meridionalis,might have provided the favorable conditions for the final bloom of the floating seaweeds.This is the first report on the bloom of subtropical U.meridionalis in the north temperate sea zone,indicating that the ecological risk of causing green tides in the future by this rapidly spreading species deserves high attention.展开更多
The pepsin and trypsin activities and some of the properties of the two enzymes of southern sheatfish larvae were studied. The results were as follows: the highest level of trypsin activity is in the foregut in all...The pepsin and trypsin activities and some of the properties of the two enzymes of southern sheatfish larvae were studied. The results were as follows: the highest level of trypsin activity is in the foregut in all measured tissues; from foregut to hindgut, trypsin activities decrease; the pH optimum of trypsin activity is pH9.0; the strongest pepsin activity is in the stomach; the proper density of haemoglobin for detecting pepsin activity is 1.0%. These data are useful in solving applied nutritional problems, such as the adequacy of artificial food to the digestive abilities of the fish.展开更多
Xanthophyll has multiple physiological functions to improve the quality of farmed animals.The present study aimed to investigate the effects of xanthophyll on the growth performance,antioxidation,immunity,pigmentation...Xanthophyll has multiple physiological functions to improve the quality of farmed animals.The present study aimed to investigate the effects of xanthophyll on the growth performance,antioxidation,immunity,pigmentation and meat quality of southern catfish(Silurus soldatovi meridionalis Chen).Juvenile southern catfish(18.35±0.04 g)were randomly allocated into 24 cages(30 juveniles per cage),and fed diets with different dietary xanthophyll levels(at 14,42,80,108,126 and 152 mg/kg,dry matter of diet)twice daily for 8 weeks.Results indicated that the diet with 80 mg/kg xanthophyll induced a higher specific growth rate(SGR),feed efficiency ratio and protein productive value.Moreover,the 80 mg/kg xanthophyll diet also increased complement 3,immunoglobulin M(IgM)and lysozyme content more than the other groups.The mRNA expression level of inflammation-related genes and antioxidant enzyme activities further confirmed the effects of 80 mg/kg dietary xanthophyll on improving immune response.The present study also found that the 126 mg/kg xanthophyll diet significantly enhanced the content of total carotenoids and xanthophyll,hydroxyproline,collagen and amino acid in muscle.The diet with 126 mg/kg xanthophylls also induced lower drip loss,thawing loss,centrifugal loss,cooking loss and higher muscle adhesiveness,cohesiveness,springiness,gumminess and chewiness than the other treatments.In conclusion,quadratic regression model analysis based on SGR and IgM revealed that the optimum xanthophyll level in the diet was 86.78 and 84.63 mg/kg,respectively.Moreover,broken line regression analysis based on xanthophyll content in dorsal skin and chewiness in muscle demonstrated that the optimal xanthophyll level was between 89.73 and 108.66 mg/kg in the diet of southern catfish(S.soldatovi meridionalis Chen).展开更多
为了解水体中铅(Pb)对鱼类早期发育阶段的毒性影响,使用人工受精获得南方鲇(Silurus meridionalis Chen)胚胎和仔鱼为研究对象,以硝酸铅(Pb(NO3)2)为毒物源,探讨研究对象在胚胎期和仔鱼期受到5个(0~400μg/L)不同浓度水平铅持续暴露、...为了解水体中铅(Pb)对鱼类早期发育阶段的毒性影响,使用人工受精获得南方鲇(Silurus meridionalis Chen)胚胎和仔鱼为研究对象,以硝酸铅(Pb(NO3)2)为毒物源,探讨研究对象在胚胎期和仔鱼期受到5个(0~400μg/L)不同浓度水平铅持续暴露、半持续暴露以及暴露后恢复处理条件下,实验鱼鳃、肝脏和肾脏抗氧酶的活性变化以及脑组织中乙酰胆碱酯酶活性情况。结果表明,恢复组实验鱼鳃、肝脏和肾脏组织中总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活性在后期恢复过程中呈升高趋势;三种组织中丙二醛(MDA)含量随着胚胎期水体Pb浓度升高而升高。持续组和半持续组实验鱼鳃、肝脏和肾脏组织中TAOC、SOD、CAT活性随着水体铅浓度升高而降低,显著低于对照组(P<0.05),丙二醛含量随着Pb浓度升高而升高,脂质过氧化程度加剧;而相同Pb浓度水平之间,持续组和半持续组实验鱼三种组织中,持续组中TAOC、SOD、CAT的活性和MDA的含量变化大于半持续组。发现:南方鲇胚胎期受重金属暴露,后期恢复饲养,其鳃、肝脏和肾脏组织中T-AOC、SOD、CAT的活性会出现恢复效应;胚胎期和仔鱼期重金属暴露存在叠加效应,且重金属对仔鱼的毒性作用更加剧烈。展开更多
基金Supported by the National Natural Science Foundation of China(30371121)the Natural Science Foundation of Chongqing the Educa-tion Committee Foundation of Chongqing~~
文摘The objective of the study was to explore the effect of acute low temperature stress on VO2 and Vf of Silurus meridionalis and Pelteobag vachelli after 10 minutes cold water bath with different temperature.The investigation was operated under the temperature of 24 ℃.It was found that the VO2 and Vf of Silurus meridionalis after 6 and 0 ℃ stress showed a decrease-increase-decrease trend while other groups showed a rapid increase then slowly recovery trend.The VO2 and Vf of Pelteobag vachelli after 0 ℃stress showed a decrease-increase-decrease trend while other groups showed an increase then slowly recovery process.It was suggested that Pelteobag vachelli was more adaptive to acute cold stress,but it cost more energy adapting to cold stress compared to Silurus meridionalis.
基金Supported by the National Natural Science Foundation of China(30371121)~~
文摘The routine metabolic rate in southern catfish juvenile(24.3-250.8 g)fed with saccharine feed(CHO)was measured in this study.Fish were fed with iso-nitrogenous(40 % crude protein)and iso-lipidic(10% crude lipid)experimental feed containing 0(control feed),15%,30% of carbohydrate level.The routine metabolic rates of 15 % and 30% dietary carbohydrate group were significantly higher than that of 0% dietary carbohydrate group.The relationship between body mass(Wt)and routine metabolic rate(Rr)of southern catfishfed with different test feed could be described as:(1)0% CHO:ln(Rr)=0.986 ln(Wt)+1.419 r2=0.922,n=25,P<0.001;(2)15% CHO:ln(Rr)=0.912 ln(Wt)+1.741 r2=0.966,n=21,P<0.001;(3)30% CHO:ln(Rr)=0.762 ln(Wt)+2.378 r2=0.958,n=21,P<0.001.The intercept was increased and mass coefficient was decreased with the increase of carbohydrate level in feed.It could be concluded that southern Silurus meridionalis had poor metabolic capacity which led the increase of routine metabolic rate of fish with small size.But with the increase of body size southern Silurus meridionalis might had a better adaptation to high carbohydrate concentration.
基金Supported by the Science&Technology Basic Resources Investigation Program of China(No.2018FY100205)the National Natural Science Foundation of China(No.41776153)+4 种基金the National Key R&D Program of China(No.2018YFD0901500)the Key Deployment Project of Centre for Ocean Mega-Research of ScienceChinese Academy of Science(No.COMS2019Q05)the Key R&D Program of Shandong Province(No.2019GSF107012)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA23050302)。
文摘The large-scale green tide caused by Ulva has occurred successively in the Yellow Sea since 2007,and new events of green tide also continued to appear in nearby sea areas,indicating an undergoing rapid development of occurrence patterns for harmful macroalgal blooms(HMBs)along coastal China.In August 2021,a green tide occurred for the first time in Bayuquan sea area of Yingkou city,Liaoning Province in the Bohai Sea.In this study,morphological and molecular approaches were used to identify the causative species as U.meridionalis,an alien subtropical alga previously found to dominate green tides in the South China Sea.According to the hydrological data of Bayuquan in summer 2021,combined with morphological and developmental observations for this alga,we hypothesized that the disturbance caused by the typhoon In-Fa might have detached the local U.meridionalis from substrates,especially for those thalli with poorly developed holdfasts,and the ensuing wave-free period with unusually high temperature,which fell in the reported optimum growth temperature for U.meridionalis,might have provided the favorable conditions for the final bloom of the floating seaweeds.This is the first report on the bloom of subtropical U.meridionalis in the north temperate sea zone,indicating that the ecological risk of causing green tides in the future by this rapidly spreading species deserves high attention.
文摘The pepsin and trypsin activities and some of the properties of the two enzymes of southern sheatfish larvae were studied. The results were as follows: the highest level of trypsin activity is in the foregut in all measured tissues; from foregut to hindgut, trypsin activities decrease; the pH optimum of trypsin activity is pH9.0; the strongest pepsin activity is in the stomach; the proper density of haemoglobin for detecting pepsin activity is 1.0%. These data are useful in solving applied nutritional problems, such as the adequacy of artificial food to the digestive abilities of the fish.
基金supported by the Foundation and Applied Basic Research Fund Project of Guangdong Province(2019A1515110606)Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai).
文摘Xanthophyll has multiple physiological functions to improve the quality of farmed animals.The present study aimed to investigate the effects of xanthophyll on the growth performance,antioxidation,immunity,pigmentation and meat quality of southern catfish(Silurus soldatovi meridionalis Chen).Juvenile southern catfish(18.35±0.04 g)were randomly allocated into 24 cages(30 juveniles per cage),and fed diets with different dietary xanthophyll levels(at 14,42,80,108,126 and 152 mg/kg,dry matter of diet)twice daily for 8 weeks.Results indicated that the diet with 80 mg/kg xanthophyll induced a higher specific growth rate(SGR),feed efficiency ratio and protein productive value.Moreover,the 80 mg/kg xanthophyll diet also increased complement 3,immunoglobulin M(IgM)and lysozyme content more than the other groups.The mRNA expression level of inflammation-related genes and antioxidant enzyme activities further confirmed the effects of 80 mg/kg dietary xanthophyll on improving immune response.The present study also found that the 126 mg/kg xanthophyll diet significantly enhanced the content of total carotenoids and xanthophyll,hydroxyproline,collagen and amino acid in muscle.The diet with 126 mg/kg xanthophylls also induced lower drip loss,thawing loss,centrifugal loss,cooking loss and higher muscle adhesiveness,cohesiveness,springiness,gumminess and chewiness than the other treatments.In conclusion,quadratic regression model analysis based on SGR and IgM revealed that the optimum xanthophyll level in the diet was 86.78 and 84.63 mg/kg,respectively.Moreover,broken line regression analysis based on xanthophyll content in dorsal skin and chewiness in muscle demonstrated that the optimal xanthophyll level was between 89.73 and 108.66 mg/kg in the diet of southern catfish(S.soldatovi meridionalis Chen).
文摘为了解水体中铅(Pb)对鱼类早期发育阶段的毒性影响,使用人工受精获得南方鲇(Silurus meridionalis Chen)胚胎和仔鱼为研究对象,以硝酸铅(Pb(NO3)2)为毒物源,探讨研究对象在胚胎期和仔鱼期受到5个(0~400μg/L)不同浓度水平铅持续暴露、半持续暴露以及暴露后恢复处理条件下,实验鱼鳃、肝脏和肾脏抗氧酶的活性变化以及脑组织中乙酰胆碱酯酶活性情况。结果表明,恢复组实验鱼鳃、肝脏和肾脏组织中总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活性在后期恢复过程中呈升高趋势;三种组织中丙二醛(MDA)含量随着胚胎期水体Pb浓度升高而升高。持续组和半持续组实验鱼鳃、肝脏和肾脏组织中TAOC、SOD、CAT活性随着水体铅浓度升高而降低,显著低于对照组(P<0.05),丙二醛含量随着Pb浓度升高而升高,脂质过氧化程度加剧;而相同Pb浓度水平之间,持续组和半持续组实验鱼三种组织中,持续组中TAOC、SOD、CAT的活性和MDA的含量变化大于半持续组。发现:南方鲇胚胎期受重金属暴露,后期恢复饲养,其鳃、肝脏和肾脏组织中T-AOC、SOD、CAT的活性会出现恢复效应;胚胎期和仔鱼期重金属暴露存在叠加效应,且重金属对仔鱼的毒性作用更加剧烈。