The gut microbiota plays an important role in host health and disease.Our understanding of the fish microbiota lags far behind our knowledge of that of humans and other mammals.Nevertheless,research has highlighted th...The gut microbiota plays an important role in host health and disease.Our understanding of the fish microbiota lags far behind our knowledge of that of humans and other mammals.Nevertheless,research has highlighted the importance of the microbiota in the health,performance,and various physiological functions of fish.The microbiota has been studied in various fish species,including model animals,economic fish,and wild fish species.The composition of the fish microbiota depends on host selection,diet,and environmental factors.The intestinal microbiota affects the nutritional metabolism,immunity,and disease resistance of the fish host,while the host regulates the intestinal microbiota in a reciprocal way through both immune and non-immune factors.Improved and novel gnotobiotic fish models have been developed,which are important for the mechanistic study of host–microbiota interactions in fish.In this review,we discuss recent progress in fish microbiota research.We describe various aspects of this research,including both studies on fish microbiota variations and fundamental research extending our knowledge of host–microbiota interaction in fish.Perspectives on how fish microbiota research may benefit fish health and industrial sustainability are also discussed.展开更多
Aquaculture is one of the fastest-growing agricultural sectors globally and is becoming increasingly important for producing sustainable and healthy diets with relatively low climate impacts.In comparison to livestock...Aquaculture is one of the fastest-growing agricultural sectors globally and is becoming increasingly important for producing sustainable and healthy diets with relatively low climate impacts.In comparison to livestock production,especially beef,seafood production has lower carbon emissions.Additionally,some species can extract carbon from aquatic environments,contributing to an extended carbon cycle.However,the potential for negative environmental consequences in aquaculture production might increase with the growing global population and demand for aquatic food.Herein,we review the environmental consequences of aquaculture production and the potential effects of different aquatic products on greenhouse gas(GHG)emissions.We also summarize approaches to improving environmental footprints for mitigating global climate change.Key elements,including improving feed efficiency,selecting suitable farmed species,and implementing sustainable farming practices and management in aquaculture,are discussed,as well as the trade-offs between aquaculture and capture fisheries.Crucially,performance gaps among farmed species underscore the potential for consumer-oriented advice to significantly reduce the effects of aquaculture on climate change.However,uncertainties and knowledge gaps related to carbon sequestration and GHG emissions in aquaculture ponds necessitate further research.Overall,holistic evaluation and strategic intervention regarding GHG emissions are fundamental and essential for achieving a sustainable,low-carbon future for aquaculture.展开更多
The objective of this study is to investigate the effects of free gossypol in cottonseed meal(CM)on the growth and intestinal health of grass carp,as well as to determine whether free gossypol is the primary factor re...The objective of this study is to investigate the effects of free gossypol in cottonseed meal(CM)on the growth and intestinal health of grass carp,as well as to determine whether free gossypol is the primary factor restricting highlevel inclusion of cottonseed meal.This study was designed with five groups:the control group(32%soybean concentrate protein),the CM group(44%CM),the cottonseed protein concentrate(CPC)group(33%CPC),and the CPC and control groups with 400 and 600 mg/kg gossypol added,designated as CON,CM,CPC,CPC+GP,and CON+GP,respectively.The experiment lasted eight weeks,and each group had three replicates.This experiment employed one-way ANOVA and Duncan's multiple comparisons of the means.The findings revealed that in comparison to the CON group,the growth of fish in the CM,CPC+GP,and CON+GP groups significantly decreased.Intestinal inflammation damage was observed.This was indicated by a significant upregulation of proinflammatory factors,including tnf-α,nf-κb,il-6,il-8,il-12β,and il-1β,along with significant downregulation of anti-inflammatory factors,including tgf-β1,il-15,and il-10.Additionally,significant downregulation of antioxidant enzyme-related genes,including nrf2,cat,CuZnsod,gpx4,and gpx1,was observed and the intestinal physical barrier function was compromised.In addition,the intestinal microbiota composition was affected,with a significant reduction in Bacillus and Cetobacterium abundances and a remarkable increase in the abundance of Aeromonas,resulting in dysregulation of the intestinal microbiota function.However,in comparison to the CM group,the growth rate of fish in the CPC group exhibited a marked increase;nonetheless,it persisted at a level lower than that observed in the CON group and the degree of intestinal damage was significantly improved.Additionally,the intestinal microbiota structure was found to be similar to that of the CON group.In conclusion,excessive CM negatively affects grass carp growth and intestinal health,whereas replacing CM with CPC mitigates these effects.Adding gossypol equivalent to CM group in CON and CPC diets reduces growth performance and impairs intestinal function,indicating gossypol as a primary limiting factor for high CM inclusion in diets.展开更多
Since the aquaculture industry is currently observing a deterioration in the flesh quality of farmed fish,the use of nutrients as additives to improve the flesh quality of farmed fish species is a viable strategy.The ...Since the aquaculture industry is currently observing a deterioration in the flesh quality of farmed fish,the use of nutrients as additives to improve the flesh quality of farmed fish species is a viable strategy.The aim of this study was to investigate the effect of dietary D-ribose(RI)on the nutritional value,texture and flavour of gibel carp(Carassius auratus gibelio).Four diets were formulated containing exogenous RI at 4 gradient levels:0(Control),0.15%(0.15RI),0.30%(0.30RI)and 0.45%(0.45RI).A total of 240 fish(150±0.31 g)were randomly distributed into 12 fibreglass tanks(150 L per tank).Triplicate tanks were randomly assigned to each diet.The feeding trial was carried out in an indoor recirculating aquaculture system for 60 d.After the feeding trial,the muscle and liver of gibel carp were analysed.The results showed that RI supplementation did not result in any negative impact on the growth performance and 0.30RI supplementation significantly increased the whole-body protein content compared to the control group.The contents of collagen and glycogen in muscle were enhanced by RI supplementation.The alterations in the flesh indicated that RI supplementation improved the texture of the flesh in terms of its water-holding capacity and hardness,therefore improving the taste.Dietary RI facilitated the deposition of amino acids and fatty acids in the muscle that contributed to the meaty taste and nutritional value.Furthermore,a combination of metabolomics and expression of key genes in liver and muscle revealed that 0.30RI activated the purine metabolism pathways by supplementing the substrate for nucleotide synthesis and thereby promoting the deposition of flavour substance in flesh.This study offers a new approach for providing healthy,nutritious and flavourful aquatic products.展开更多
Chlorella meal is a potential protein source for aquafeeds.However,the physiological response of carnivorous fish fed Chlorella meal remains elusive.This study evaluated the effects of replacing dietary fish meal with...Chlorella meal is a potential protein source for aquafeeds.However,the physiological response of carnivorous fish fed Chlorella meal remains elusive.This study evaluated the effects of replacing dietary fish meal with Chlorella meal on growth performance,pigmentation,and liver health in largemouth bass.Five diets were formulated to replace dietary fish meal of 0%(C0,control),25%(C25),50%(C50),75%(C75),and 100%(C100)with Chlorella meal,respectively.Total 300 fish(17.6±0.03 g)were randomly assigned to 15 tanks(3 tanks/group).Fish were fed the experimental diet twice daily for 8 weeks.The increased dietary Chlorella meal quadratically influenced the final body weight(FBW),weight gain rate(WGR),specific growth rate(SGR),and feed intake(FI),which were significantly lower in the C100 group than in the other groups(P<0.05).The feed conversion ratio(FCR)increased linearly or quadratically with dietary Chlorella meal.Dietary Chlorella meal linearly or quadratically increased the lutein content of plasma,liver,and dorsal muscle of largemouth bass(P<0.05).Compared to the C0 group,all supplemented Chlorella meal groups significantly improved the yellowness(b*)of the dorsal body(1.5 to 2.0 fold),abdominal body(1.5 to 1.8 fold),and dorsal muscle(3.8 to 5.4 fold)of largemouth bass(P<0.05).In addition,compared to the C0 group,the liver vacuolation area of fish was significantly increased in the C75 and C100 groups(P<0.05).Transcriptional levels of apoptosis-related genes of b-cell lymphoma-2(bcl2),caspase-9-like(casp9),and caspase-3a(casp3)were markedly upregulated(0.9 to 1.6 fold)in the C100 group compared to the C0 group(P<0.05).Based on the quadratic regression analysis between FBW,WGR,or SGR and dietary Chlorella meal level,largemouth bass had the best growth when replacing 31.7%to 32.6%of fish meal with 15.03%to 15.43%dietary Chlorella meal.The present results indicated that dietary supplementation with Chlorella meal(11.85%to 47.45%)significantly enhanced the pigmentation;however,total replacement of fish meal(40%)with Chlorella meal(47.45%)caused growth retardation,apoptosis,and liver damage in largemouth bass.展开更多
Hyperglycemia in type 2 diabetes results from an inability of insulin to regulate gluconeogenesis.To characterize the role of the insulin/insulin receptor pathway in glycometabolism and type 2 diabetes,we created a ze...Hyperglycemia in type 2 diabetes results from an inability of insulin to regulate gluconeogenesis.To characterize the role of the insulin/insulin receptor pathway in glycometabolism and type 2 diabetes,we created a zebrafish model in which insulin receptors a and b(insra and insrb) have been ablated.We first observed that insra and insrb were both expressed abundantly during embryonic development and in various adult tissues.Increased expression of insulin and number of b-cells were observed in insra-/-/-insrb-/-fish together with higher glucose in insra-/-,insrb-/-,or insra-/-/-insrb-/-fish,indicating that insra and insrb were knocked out effectively.However,compared to the wild-type fish,insra-/-/-insrb-/-fish died between 5 and 16 days post-fertilization(dpf) with severe pericardial edema and increased level of cell apoptosis,which was not induced by increased total body glucose content.Increased gluconeogenesis and decreased glycolysis were also observed in both single and double knockout fish,but no mortality or malformation was observed in single knockout fish.Given the importance of insulin receptors in glucose homeostasis and embryonic development,transcriptome analysis was used to provide an important model of defective insulin signaling and to study its developmental consequences in zebrafish.The results indicated that both insra and insrb played a pivotal role in glucose metabolism and embryonic development,and insra was more critical than insrb in the insulin signaling pathway.展开更多
Improvement in fish feed conversion efficiency(FCE)is beneficial for sustaining global food fish supplies.Here,we show that a set of polymorphisms at locus of the corticotropin releasing hormone receptor 2(crhr2),whic...Improvement in fish feed conversion efficiency(FCE)is beneficial for sustaining global food fish supplies.Here,we show that a set of polymorphisms at locus of the corticotropin releasing hormone receptor 2(crhr2),which is involved in hypothalamuspituitary-interrenal(HPI)axis signaling,is associated with improved FCE in farmed allogynogenetic gibel carp strain CAS Ⅲ compared with that in the wild gibel carp strain Dongting(DT).This set of polymorphisms downregulates the expression levels of crhr2 mRNA in the brain and pituitary tissues in gibel carp strain CAS Ⅲ compared with those in strain DT.Furthermore,compromised HPI axis signaling is observed in gibel carp strain CAS Ⅲ,such as decreased α-melanocyte stimulating hormone protein levels,plasma cortisol content,and stress responses.Moreover,enhanced activation of protein kinase B/mammalian target of rapamycin complex 1 signaling observed in the muscle tissue of strain CAS Ⅲ in comparison to that in strain DT indicated elevated anabolic metabolism in strain CAS Ⅲ.Thus,these studies demonstrate that the genetic markers associated with compromised HPI axis signaling,such as crhr2,are potentially useful for genetic selection toward improvement in farmed fish growth and FCE,which would reduce fishmeal consumption and thereby indirectly facilitate sustainable fisheries.展开更多
基金supported by the National Natural Science Foundation of China(31925038 and 32122088)。
文摘The gut microbiota plays an important role in host health and disease.Our understanding of the fish microbiota lags far behind our knowledge of that of humans and other mammals.Nevertheless,research has highlighted the importance of the microbiota in the health,performance,and various physiological functions of fish.The microbiota has been studied in various fish species,including model animals,economic fish,and wild fish species.The composition of the fish microbiota depends on host selection,diet,and environmental factors.The intestinal microbiota affects the nutritional metabolism,immunity,and disease resistance of the fish host,while the host regulates the intestinal microbiota in a reciprocal way through both immune and non-immune factors.Improved and novel gnotobiotic fish models have been developed,which are important for the mechanistic study of host–microbiota interactions in fish.In this review,we discuss recent progress in fish microbiota research.We describe various aspects of this research,including both studies on fish microbiota variations and fundamental research extending our knowledge of host–microbiota interaction in fish.Perspectives on how fish microbiota research may benefit fish health and industrial sustainability are also discussed.
基金funded by the National Key R&D Program of China(grant number 2024YFE0105900)the National Natural Science Foundation of China(grant number 31902391)+1 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(grant number 2023000048)China Agriculture Research System of MOF and MARA(grant number CARS-46).
文摘Aquaculture is one of the fastest-growing agricultural sectors globally and is becoming increasingly important for producing sustainable and healthy diets with relatively low climate impacts.In comparison to livestock production,especially beef,seafood production has lower carbon emissions.Additionally,some species can extract carbon from aquatic environments,contributing to an extended carbon cycle.However,the potential for negative environmental consequences in aquaculture production might increase with the growing global population and demand for aquatic food.Herein,we review the environmental consequences of aquaculture production and the potential effects of different aquatic products on greenhouse gas(GHG)emissions.We also summarize approaches to improving environmental footprints for mitigating global climate change.Key elements,including improving feed efficiency,selecting suitable farmed species,and implementing sustainable farming practices and management in aquaculture,are discussed,as well as the trade-offs between aquaculture and capture fisheries.Crucially,performance gaps among farmed species underscore the potential for consumer-oriented advice to significantly reduce the effects of aquaculture on climate change.However,uncertainties and knowledge gaps related to carbon sequestration and GHG emissions in aquaculture ponds necessitate further research.Overall,holistic evaluation and strategic intervention regarding GHG emissions are fundamental and essential for achieving a sustainable,low-carbon future for aquaculture.
文摘The objective of this study is to investigate the effects of free gossypol in cottonseed meal(CM)on the growth and intestinal health of grass carp,as well as to determine whether free gossypol is the primary factor restricting highlevel inclusion of cottonseed meal.This study was designed with five groups:the control group(32%soybean concentrate protein),the CM group(44%CM),the cottonseed protein concentrate(CPC)group(33%CPC),and the CPC and control groups with 400 and 600 mg/kg gossypol added,designated as CON,CM,CPC,CPC+GP,and CON+GP,respectively.The experiment lasted eight weeks,and each group had three replicates.This experiment employed one-way ANOVA and Duncan's multiple comparisons of the means.The findings revealed that in comparison to the CON group,the growth of fish in the CM,CPC+GP,and CON+GP groups significantly decreased.Intestinal inflammation damage was observed.This was indicated by a significant upregulation of proinflammatory factors,including tnf-α,nf-κb,il-6,il-8,il-12β,and il-1β,along with significant downregulation of anti-inflammatory factors,including tgf-β1,il-15,and il-10.Additionally,significant downregulation of antioxidant enzyme-related genes,including nrf2,cat,CuZnsod,gpx4,and gpx1,was observed and the intestinal physical barrier function was compromised.In addition,the intestinal microbiota composition was affected,with a significant reduction in Bacillus and Cetobacterium abundances and a remarkable increase in the abundance of Aeromonas,resulting in dysregulation of the intestinal microbiota function.However,in comparison to the CM group,the growth rate of fish in the CPC group exhibited a marked increase;nonetheless,it persisted at a level lower than that observed in the CON group and the degree of intestinal damage was significantly improved.Additionally,the intestinal microbiota structure was found to be similar to that of the CON group.In conclusion,excessive CM negatively affects grass carp growth and intestinal health,whereas replacing CM with CPC mitigates these effects.Adding gossypol equivalent to CM group in CON and CPC diets reduces growth performance and impairs intestinal function,indicating gossypol as a primary limiting factor for high CM inclusion in diets.
基金supported by the National Key R&D Program of China(2018YFD0900400)the earmarked fund for CARS(CARS-45)China and National Natural Science Foundation of China(U21A20266)。
文摘Since the aquaculture industry is currently observing a deterioration in the flesh quality of farmed fish,the use of nutrients as additives to improve the flesh quality of farmed fish species is a viable strategy.The aim of this study was to investigate the effect of dietary D-ribose(RI)on the nutritional value,texture and flavour of gibel carp(Carassius auratus gibelio).Four diets were formulated containing exogenous RI at 4 gradient levels:0(Control),0.15%(0.15RI),0.30%(0.30RI)and 0.45%(0.45RI).A total of 240 fish(150±0.31 g)were randomly distributed into 12 fibreglass tanks(150 L per tank).Triplicate tanks were randomly assigned to each diet.The feeding trial was carried out in an indoor recirculating aquaculture system for 60 d.After the feeding trial,the muscle and liver of gibel carp were analysed.The results showed that RI supplementation did not result in any negative impact on the growth performance and 0.30RI supplementation significantly increased the whole-body protein content compared to the control group.The contents of collagen and glycogen in muscle were enhanced by RI supplementation.The alterations in the flesh indicated that RI supplementation improved the texture of the flesh in terms of its water-holding capacity and hardness,therefore improving the taste.Dietary RI facilitated the deposition of amino acids and fatty acids in the muscle that contributed to the meaty taste and nutritional value.Furthermore,a combination of metabolomics and expression of key genes in liver and muscle revealed that 0.30RI activated the purine metabolism pathways by supplementing the substrate for nucleotide synthesis and thereby promoting the deposition of flavour substance in flesh.This study offers a new approach for providing healthy,nutritious and flavourful aquatic products.
基金National Natural Science Foundation of China(U21A20266,31972771,31972805,31672670)China Agriculture Research System of MOF and MARA(CARS-46)+2 种基金National Key R&D Program of China(2018YFD0900400)Fund Project in State Key Laboratory of Freshwater Ecology and Biotechnology(2019FBZ02,2019FBZ05)Hubei High-tech Innovation and Business Incubation Center(2019-02-055).
文摘Chlorella meal is a potential protein source for aquafeeds.However,the physiological response of carnivorous fish fed Chlorella meal remains elusive.This study evaluated the effects of replacing dietary fish meal with Chlorella meal on growth performance,pigmentation,and liver health in largemouth bass.Five diets were formulated to replace dietary fish meal of 0%(C0,control),25%(C25),50%(C50),75%(C75),and 100%(C100)with Chlorella meal,respectively.Total 300 fish(17.6±0.03 g)were randomly assigned to 15 tanks(3 tanks/group).Fish were fed the experimental diet twice daily for 8 weeks.The increased dietary Chlorella meal quadratically influenced the final body weight(FBW),weight gain rate(WGR),specific growth rate(SGR),and feed intake(FI),which were significantly lower in the C100 group than in the other groups(P<0.05).The feed conversion ratio(FCR)increased linearly or quadratically with dietary Chlorella meal.Dietary Chlorella meal linearly or quadratically increased the lutein content of plasma,liver,and dorsal muscle of largemouth bass(P<0.05).Compared to the C0 group,all supplemented Chlorella meal groups significantly improved the yellowness(b*)of the dorsal body(1.5 to 2.0 fold),abdominal body(1.5 to 1.8 fold),and dorsal muscle(3.8 to 5.4 fold)of largemouth bass(P<0.05).In addition,compared to the C0 group,the liver vacuolation area of fish was significantly increased in the C75 and C100 groups(P<0.05).Transcriptional levels of apoptosis-related genes of b-cell lymphoma-2(bcl2),caspase-9-like(casp9),and caspase-3a(casp3)were markedly upregulated(0.9 to 1.6 fold)in the C100 group compared to the C0 group(P<0.05).Based on the quadratic regression analysis between FBW,WGR,or SGR and dietary Chlorella meal level,largemouth bass had the best growth when replacing 31.7%to 32.6%of fish meal with 15.03%to 15.43%dietary Chlorella meal.The present results indicated that dietary supplementation with Chlorella meal(11.85%to 47.45%)significantly enhanced the pigmentation;however,total replacement of fish meal(40%)with Chlorella meal(47.45%)caused growth retardation,apoptosis,and liver damage in largemouth bass.
基金supported by the National Basic Research Program of China(2014CB138602)the National Natural Science Foundation of China(31672670)+2 种基金the Chinese Academy of Sciences(XDA08010405)the China Agriculture Research System(CARS-46-19)the Fund Project in State Key Laboratory of Freshwater Ecology and Biotechnology(2016FBZ05)
文摘Hyperglycemia in type 2 diabetes results from an inability of insulin to regulate gluconeogenesis.To characterize the role of the insulin/insulin receptor pathway in glycometabolism and type 2 diabetes,we created a zebrafish model in which insulin receptors a and b(insra and insrb) have been ablated.We first observed that insra and insrb were both expressed abundantly during embryonic development and in various adult tissues.Increased expression of insulin and number of b-cells were observed in insra-/-/-insrb-/-fish together with higher glucose in insra-/-,insrb-/-,or insra-/-/-insrb-/-fish,indicating that insra and insrb were knocked out effectively.However,compared to the wild-type fish,insra-/-/-insrb-/-fish died between 5 and 16 days post-fertilization(dpf) with severe pericardial edema and increased level of cell apoptosis,which was not induced by increased total body glucose content.Increased gluconeogenesis and decreased glycolysis were also observed in both single and double knockout fish,but no mortality or malformation was observed in single knockout fish.Given the importance of insulin receptors in glucose homeostasis and embryonic development,transcriptome analysis was used to provide an important model of defective insulin signaling and to study its developmental consequences in zebrafish.The results indicated that both insra and insrb played a pivotal role in glucose metabolism and embryonic development,and insra was more critical than insrb in the insulin signaling pathway.
基金supported by the National Key Research and Development Program of China(2018YFD0900404)the Pilot Program A Project from the Chinese Academy of Sciences(XDA24010206)+2 种基金State Key Laboratory of Freshwater Ecology and Biotechnology(2019FBZ05)the National Natural Science Foundation of China(31530077)China Postdoctoral Science Foundation(2020M682527)。
文摘Improvement in fish feed conversion efficiency(FCE)is beneficial for sustaining global food fish supplies.Here,we show that a set of polymorphisms at locus of the corticotropin releasing hormone receptor 2(crhr2),which is involved in hypothalamuspituitary-interrenal(HPI)axis signaling,is associated with improved FCE in farmed allogynogenetic gibel carp strain CAS Ⅲ compared with that in the wild gibel carp strain Dongting(DT).This set of polymorphisms downregulates the expression levels of crhr2 mRNA in the brain and pituitary tissues in gibel carp strain CAS Ⅲ compared with those in strain DT.Furthermore,compromised HPI axis signaling is observed in gibel carp strain CAS Ⅲ,such as decreased α-melanocyte stimulating hormone protein levels,plasma cortisol content,and stress responses.Moreover,enhanced activation of protein kinase B/mammalian target of rapamycin complex 1 signaling observed in the muscle tissue of strain CAS Ⅲ in comparison to that in strain DT indicated elevated anabolic metabolism in strain CAS Ⅲ.Thus,these studies demonstrate that the genetic markers associated with compromised HPI axis signaling,such as crhr2,are potentially useful for genetic selection toward improvement in farmed fish growth and FCE,which would reduce fishmeal consumption and thereby indirectly facilitate sustainable fisheries.
