Mature wild-type yellow catfish( Pelteobagrus fulvidraco Richardson) individuals with excellent traits have been screened from the Yangtze River as broodstock to establish the germplasm bank of pure-line yellow catfis...Mature wild-type yellow catfish( Pelteobagrus fulvidraco Richardson) individuals with excellent traits have been screened from the Yangtze River as broodstock to establish the germplasm bank of pure-line yellow catfish by artificial gynogenesis technique and hormonal sex reversal method. Based on pure lines of yellow catfish,super-males and physiological females of yellow catfish were selected by GMT technique,hormonal sex reversal method and test-crossing to establish the germplasm bank of YY physiological females( YY♀). The propagation system of male yellow catfish( XY♂) was established based on the combination of super-males( YY♂) and pure-line female( XX♀) for large-scale production of pure-line yellow catfish males,which effectively overcome the disadvantages in the production of common fingerlings and male fingerlings using low-grade fish with slow growth and small size at the bottom of the fish grader as broodfish,such as progeny germplasm degeneration,loss of growth vigor and reduction of breeding benefits. The technical route of breeding pure-line YY physiological females( YY♀) and YY super-males( YY♂) laid the foundation for large-scale production of environmentally friendly yellow catfish males with pure germplasm and strong stress resistance,and provided an efficient,stable,healthy,environmentally friendly,energy-saving and income-increasing approach for sustainable development of yellow catfish breeding industry.展开更多
This paper describes and discuases a new bucephalid species, Rhoporhynchus lini,from the swim bladder of yellow catfish, Pseudobagrous fulvidraco, for Nanhai County of GuangdngProvince in China. lt is chimterized driu...This paper describes and discuases a new bucephalid species, Rhoporhynchus lini,from the swim bladder of yellow catfish, Pseudobagrous fulvidraco, for Nanhai County of GuangdngProvince in China. lt is chimterized driuly by its wide flat foliate body, largr size, degeneratedrhynchus, voldrinous saccular intestine, dendrihc vitellaria, short uterus, limited locality of the repro-ductive organs and site of infechon in fish swim bladder. It is certainly allocated to the subfamily Bu-cephalinae according to its relative locallty of oveq and testes (ovary pretesticular). But it differs evident-ly from the species in all other genera of the subfamily. Therefore, a new genus, Rhoporhynchus, iserected with R. lini as the type species.展开更多
This study was to evaluate the potential of a host-associated Bacillus velezensis as a probiotic for hybrid yellow catfish(Pelteobagrus fulvidraco♀×Pelteobagrus vachelli♂).Diets(B0 to B5)containing 0,0.90×...This study was to evaluate the potential of a host-associated Bacillus velezensis as a probiotic for hybrid yellow catfish(Pelteobagrus fulvidraco♀×Pelteobagrus vachelli♂).Diets(B0 to B5)containing 0,0.90×10^(8),0.80×109,0.85×10^(10),0.90×10^(11),0.83×10^(12)CFU/kg B.velezensis YFI-E109 were fed to the fish with initial weight(3.07±0.08 g)in a recirculating aquaculture system for six weeks with three replicates,respectively.Probiotic effects were analyzed based on growth,body composition,liver and gut morphology,gut microbiome,and liver metabolome.Analysis of the bacterial genome has shown that the most abundant genes in B.velezensis YFI-E109 were distributed in carbohydrate and amino acid metabolism.Fish in groups B3 and B4 had better growth performance,and higher intestinal amylase(AMS)and lipase(LPS)activities compared with other groups(P<0.05).Fish in groups B0 and B5 showed significant liver damage,while this status improved in group B3.The liver malondialdehyde(MDA)content in group B3 was lower than that in other groups(P<0.05).The abundance of Mycoplasma,Ralstonia and Acinetobacter was significantly reduced in B3 and B5 compared to B0.The amino acid and carbohydrate metabolism pathways were enriched in group B3 compared with group B0.In conclusion,dietary B.velezensis YFI-E109 supplementation has the potential to improve growth,liver metabolism,and liver and gut health,and reshape the gut microbiome of hybrid yellow catfish.Excessive B.velezensis YFI-E109 reduced the prebiotic effects.The recommended dietary supplementation of B.velezensis YFI-E109 is 0.31×10^(10) to 0.77×10^(11)CFU/kg for hybrid yellow catfish according to the quadratic regression method by plotting specific growth rate(SGR),feed conversion ratio(FCR),MDA and activities of AMS against dietary B.velezensis YFI-E109 levels.展开更多
The catfishes are a group of economically important freshwater fish in China,which in recent years have suffered heavy losses as a result of bacterial outbreaks.In this study,we examined the diversity of the microbiom...The catfishes are a group of economically important freshwater fish in China,which in recent years have suffered heavy losses as a result of bacterial outbreaks.In this study,we examined the diversity of the microbiome of infected skin mucus of yellow catfish(Pelteobagrus fulvidraco)and channel catfish(Ictalurus punctatus)and analyzed the bacterial pathogens.We found several common pathogenic bacteria,such as Aeromonas spp.,Vibrio spp.,Moraxella spp.and Proteus spp.present in both fish species,but with significantly different bacterial community structures.We isolated and cultured Aeromonas veronii and Proteus mirabilis and validated their infectivity in zebrafish(Danio rerio)and yellow catfish.Intraperitoneal injection of either bacteria into zebrafish,but not immersion,caused 100%mortality and ovary fragmentation.Yellow catfish was more sensitive than zebrafish with 100%mortality in the immersion challenges with A.veronii or P.mirabilis,and with a higher abundance of A.veronii in the P.mirabilis-challenged group compared to control.To our knowledge,this is the first study on the pathogenicity of P.mirabilis in yellow catfish,and the results will help to develop effective strategies for the disease prevention and control in catfish farming.展开更多
This experiment was conducted to investigate the effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile...This experiment was conducted to investigate the effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile yellow catfish(Pelteobagrus fulvidraco). Five isonitrogenous and isolipidic diets(42%protein and 9% lipid) were formulated to contain graded levels of arginine(2.44%, 2.64%, 2.81%, 3.01% and3.23% of diet), by supplementing L-Arginine HCI. Seven hundred juvenile yellow catfish with an initial average body weight of 1.13 ± 0.02 g were randomly divided into 5 groups with 4 replicates of 35 fish each and each group was fed one of the diets. After 56 d feeding, fish were exposed to 100 mg/L of ammonia-nitrogen for 72 h. The results showed that weight gain(WG) and specific growth rate(SGR) in2.64% and 2.81% groups were significantly higher than those in 3.23% group(P < 0.05). The feed conversation ratio(FCR) in 2,64%, 2,81% and 3.01% groups was significantly decreased when compared with3,23% group. The protein efficiency ratio(PER) in 2.64% group was significantly higher than that in 2.44%and 3.23% groups(P < 0.05). The condition factor(CF) of fish was significantly higher in 2.81% group than that in 2,44% group(P < 0.05). Dietary arginine levels had no significant effect on hepatosomatic index(HSI), viscerosomatic index(VSI), and whole-body dry matter, crude protein, crude lipid, ash contents, as well as serum total protein(TP), triglyceride(TG), glucose(GLU), urea nitrogen(UN) contents and aspartate aminotransferase(AST), alanine aminotransferase(ALT) activities(P> 0.05). After the fish were challenged to ammonia-nitrogen for 72 h, their cumulative mortality rate in 2.81% group was significantly lower than that in 2.44% group(P < 0.05). The results suggested that dietary arginine level at 2.81%could optimize anti-ammonia-nitrogen stress ability of juvenile yellow catfish and a level of 3.23%arginine seemed to depress the growth performance of fish and decreased their tolerance to the ammonia-nitrogen stress under current study. A quadratic regression analysis based on WG indicated that the optimal dietary arginine requirement of juvenile yellow catfish was estimated to be 2.74% of the diet(6.45% of dietary protein) under current culture conditions.展开更多
Mucosal vaccination,which has the potential to induce both mucosal and systemic immune responses,is considered the most suitable method of preventing infectious diseases in farmed fish.Aeromonas veronii and Edwardsiel...Mucosal vaccination,which has the potential to induce both mucosal and systemic immune responses,is considered the most suitable method of preventing infectious diseases in farmed fish.Aeromonas veronii and Edwardsiella ictaluri are two pathogenic bacteria found in yellow catfish and often infect the fish through mucosal surfaces.Delivery of a bivalent inactivated vaccine by injection has been shown to induce a strong systemic immune response against both bacterial infections.However,mucosal immune responses and protective efficiency induced by this inactivated vaccine administrated via immersion are yet to be investigated.We developed a bivalent vaccine containing formalin-inactivated A.veronii and E.ictaluri and evaluated the immune response in yellow catfish after immersion vaccination using body fluids biochemistry indices,agglutinating antibody titers,and the expression level of immune-related genes in the skin,gills,spleen,and head kidney.The activities of innate immune-related enzymes and specific agglutination antibody titers in body fluids,as well as the expression of innate and adaptive immune-related genes in both the mucosal and systemic tissues of vaccinated fish,were significantly higher than that in control fish.Next,we assessed the protective efficacy by a challenge model of virulent strains of E.ictaluri and A.veronii.The relative survival percent of vaccinated fish was 80%and 87%after challenging fish with E.ictaluri and A.veronii,respectively,which was higher than unvaccinated control fish(43%and 57%).These results confirm that the bivalent inactivated vaccine administered via immersion induces a strong mucosal immune response and confers good protection against both E.ictaluri and A.veronii.Our results also reinforce the notion that immersion vaccination could stimulate both mucosal and systemic immunity contributing to protection against pathogens.展开更多
The sex-determining genes are found to be variable among different fish species. Yellow catfish(Pelteobagrus fulvidraco) is an important aquaculture fish species in China with XX/XY sex-determining type. Recently, YY ...The sex-determining genes are found to be variable among different fish species. Yellow catfish(Pelteobagrus fulvidraco) is an important aquaculture fish species in China with XX/XY sex-determining type. Recently, YY super-male yellow catfish has been successfully produced by combining hormonalinduced sex reversal method with sex chromosome-linked markers. Here, we identified a novel PDZ domain-containing gene in yellow catfish designated as pfpdz1, in whose intron the sex-linked marker was located. The coding sequence of pfpdz1 in Y chromosome was identical to that in X chromosome except a missense SNP(A/T) that changes an amino acid(E8V) in the N-terminal region. Pfpdz1 displayed male-specific expression during sex differentiation. Overexpression of pfpdz1 using additive transgenesis induces XX ovary to differentiate into testis-like tissue, while the targeted inactivation of pfpdz1 in Y chromosome using CRISPR/Cas9-mediated mutagenesis triggers ovarian differentiation. Furthermore,we demonstrated that pfpdz1 initiates testicular differentiation through upregulating expression of amh, dmrt1 and sox9a1, as well as downregulating expression of cyp19a1, foxl2 and wnt4. Our data provide functional evidence that pfpdz1 is significant for male differentiation and maintenance in yellow catfish.展开更多
Mitogen-activated protein kinases(MAPK) and nuclear factor kappa B(NF-κB) pathways are considered to be two crucial intracellular signaling cascades in pro-inflammatory responses.In this study,we reported the coding ...Mitogen-activated protein kinases(MAPK) and nuclear factor kappa B(NF-κB) pathways are considered to be two crucial intracellular signaling cascades in pro-inflammatory responses.In this study,we reported the coding sequences(CDS) of MAPKp38 and NF-κBp65 from yellow catfish.We also investigated the gene structure,expression patterns and functional role in yellow catfish.The CDS of MAPKp38 is1,086 bp encoding 361 amino acids(AA).The MAPKp38 protein has a long highly conserved serine/threonine protein kinases catalytic domain.The NF-κBp65 CDS is 1,794 bp,and the gene encodes 597 AA,with a Rel homology domain(RHD) which consists of a RHD-DNA-binding domain and an Ig-like,plexins,transcription factors(IPT) domain.Moreover,MAPKp38 and NF-κBp65 protein of bony fish and other vertebrates have a single clade.Quantitative real-time PCR analysis revealed the presence of the MAPKp38 and NF-κBp65 transcript in 12 tissues of healthy yellow catfish.The highest expression levels of MAPKp38 and NF-κBp65 were detected in the heart and liver,respectively.Upon stimulation with an intraperitoneal injection of lipopolysaccharide(LPS),the expression levels of MAPKp38 and NF-κBp65 were up-regulated in the intestine.These results indicated that MAPKp38 and NF-κBp65 play important roles in mediating the response protection against LPS in yellow catfish.展开更多
基金Supported by Implementation Plan of Subsidy Project for the Reform and Construction of Grassroots Agricultural Technology Extension System
文摘Mature wild-type yellow catfish( Pelteobagrus fulvidraco Richardson) individuals with excellent traits have been screened from the Yangtze River as broodstock to establish the germplasm bank of pure-line yellow catfish by artificial gynogenesis technique and hormonal sex reversal method. Based on pure lines of yellow catfish,super-males and physiological females of yellow catfish were selected by GMT technique,hormonal sex reversal method and test-crossing to establish the germplasm bank of YY physiological females( YY♀). The propagation system of male yellow catfish( XY♂) was established based on the combination of super-males( YY♂) and pure-line female( XX♀) for large-scale production of pure-line yellow catfish males,which effectively overcome the disadvantages in the production of common fingerlings and male fingerlings using low-grade fish with slow growth and small size at the bottom of the fish grader as broodfish,such as progeny germplasm degeneration,loss of growth vigor and reduction of breeding benefits. The technical route of breeding pure-line YY physiological females( YY♀) and YY super-males( YY♂) laid the foundation for large-scale production of environmentally friendly yellow catfish males with pure germplasm and strong stress resistance,and provided an efficient,stable,healthy,environmentally friendly,energy-saving and income-increasing approach for sustainable development of yellow catfish breeding industry.
文摘This paper describes and discuases a new bucephalid species, Rhoporhynchus lini,from the swim bladder of yellow catfish, Pseudobagrous fulvidraco, for Nanhai County of GuangdngProvince in China. lt is chimterized driuly by its wide flat foliate body, largr size, degeneratedrhynchus, voldrinous saccular intestine, dendrihc vitellaria, short uterus, limited locality of the repro-ductive organs and site of infechon in fish swim bladder. It is certainly allocated to the subfamily Bu-cephalinae according to its relative locallty of oveq and testes (ovary pretesticular). But it differs evident-ly from the species in all other genera of the subfamily. Therefore, a new genus, Rhoporhynchus, iserected with R. lini as the type species.
基金supported by the National Key R&D Program of China(Grant No.2022YFD2400902)China Agricultural Research System(Grant/Award Number:CARS-46)the Fund of Fujian Key Laboratory of Functional Aquafeed and Culture Environment Control(FACE20200004).
文摘This study was to evaluate the potential of a host-associated Bacillus velezensis as a probiotic for hybrid yellow catfish(Pelteobagrus fulvidraco♀×Pelteobagrus vachelli♂).Diets(B0 to B5)containing 0,0.90×10^(8),0.80×109,0.85×10^(10),0.90×10^(11),0.83×10^(12)CFU/kg B.velezensis YFI-E109 were fed to the fish with initial weight(3.07±0.08 g)in a recirculating aquaculture system for six weeks with three replicates,respectively.Probiotic effects were analyzed based on growth,body composition,liver and gut morphology,gut microbiome,and liver metabolome.Analysis of the bacterial genome has shown that the most abundant genes in B.velezensis YFI-E109 were distributed in carbohydrate and amino acid metabolism.Fish in groups B3 and B4 had better growth performance,and higher intestinal amylase(AMS)and lipase(LPS)activities compared with other groups(P<0.05).Fish in groups B0 and B5 showed significant liver damage,while this status improved in group B3.The liver malondialdehyde(MDA)content in group B3 was lower than that in other groups(P<0.05).The abundance of Mycoplasma,Ralstonia and Acinetobacter was significantly reduced in B3 and B5 compared to B0.The amino acid and carbohydrate metabolism pathways were enriched in group B3 compared with group B0.In conclusion,dietary B.velezensis YFI-E109 supplementation has the potential to improve growth,liver metabolism,and liver and gut health,and reshape the gut microbiome of hybrid yellow catfish.Excessive B.velezensis YFI-E109 reduced the prebiotic effects.The recommended dietary supplementation of B.velezensis YFI-E109 is 0.31×10^(10) to 0.77×10^(11)CFU/kg for hybrid yellow catfish according to the quadratic regression method by plotting specific growth rate(SGR),feed conversion ratio(FCR),MDA and activities of AMS against dietary B.velezensis YFI-E109 levels.
基金supported by National Key Research and Development Program of China[2018YFD0900601]The Belt and Road international joint laboratory construction projects of science and technology innovation action plan from Science and Technology Commission of Shanghai Municipality[19590750500]to L.Chen.
文摘The catfishes are a group of economically important freshwater fish in China,which in recent years have suffered heavy losses as a result of bacterial outbreaks.In this study,we examined the diversity of the microbiome of infected skin mucus of yellow catfish(Pelteobagrus fulvidraco)and channel catfish(Ictalurus punctatus)and analyzed the bacterial pathogens.We found several common pathogenic bacteria,such as Aeromonas spp.,Vibrio spp.,Moraxella spp.and Proteus spp.present in both fish species,but with significantly different bacterial community structures.We isolated and cultured Aeromonas veronii and Proteus mirabilis and validated their infectivity in zebrafish(Danio rerio)and yellow catfish.Intraperitoneal injection of either bacteria into zebrafish,but not immersion,caused 100%mortality and ovary fragmentation.Yellow catfish was more sensitive than zebrafish with 100%mortality in the immersion challenges with A.veronii or P.mirabilis,and with a higher abundance of A.veronii in the P.mirabilis-challenged group compared to control.To our knowledge,this is the first study on the pathogenicity of P.mirabilis in yellow catfish,and the results will help to develop effective strategies for the disease prevention and control in catfish farming.
基金supported by the National Natural Science Foundation of China (31402307)the construction of public service platform for the evaluation of the value of aquatic feed and feed additives in Guangdong Province(2015A040404033)
文摘This experiment was conducted to investigate the effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile yellow catfish(Pelteobagrus fulvidraco). Five isonitrogenous and isolipidic diets(42%protein and 9% lipid) were formulated to contain graded levels of arginine(2.44%, 2.64%, 2.81%, 3.01% and3.23% of diet), by supplementing L-Arginine HCI. Seven hundred juvenile yellow catfish with an initial average body weight of 1.13 ± 0.02 g were randomly divided into 5 groups with 4 replicates of 35 fish each and each group was fed one of the diets. After 56 d feeding, fish were exposed to 100 mg/L of ammonia-nitrogen for 72 h. The results showed that weight gain(WG) and specific growth rate(SGR) in2.64% and 2.81% groups were significantly higher than those in 3.23% group(P < 0.05). The feed conversation ratio(FCR) in 2,64%, 2,81% and 3.01% groups was significantly decreased when compared with3,23% group. The protein efficiency ratio(PER) in 2.64% group was significantly higher than that in 2.44%and 3.23% groups(P < 0.05). The condition factor(CF) of fish was significantly higher in 2.81% group than that in 2,44% group(P < 0.05). Dietary arginine levels had no significant effect on hepatosomatic index(HSI), viscerosomatic index(VSI), and whole-body dry matter, crude protein, crude lipid, ash contents, as well as serum total protein(TP), triglyceride(TG), glucose(GLU), urea nitrogen(UN) contents and aspartate aminotransferase(AST), alanine aminotransferase(ALT) activities(P> 0.05). After the fish were challenged to ammonia-nitrogen for 72 h, their cumulative mortality rate in 2.81% group was significantly lower than that in 2.44% group(P < 0.05). The results suggested that dietary arginine level at 2.81%could optimize anti-ammonia-nitrogen stress ability of juvenile yellow catfish and a level of 3.23%arginine seemed to depress the growth performance of fish and decreased their tolerance to the ammonia-nitrogen stress under current study. A quadratic regression analysis based on WG indicated that the optimal dietary arginine requirement of juvenile yellow catfish was estimated to be 2.74% of the diet(6.45% of dietary protein) under current culture conditions.
文摘Mucosal vaccination,which has the potential to induce both mucosal and systemic immune responses,is considered the most suitable method of preventing infectious diseases in farmed fish.Aeromonas veronii and Edwardsiella ictaluri are two pathogenic bacteria found in yellow catfish and often infect the fish through mucosal surfaces.Delivery of a bivalent inactivated vaccine by injection has been shown to induce a strong systemic immune response against both bacterial infections.However,mucosal immune responses and protective efficiency induced by this inactivated vaccine administrated via immersion are yet to be investigated.We developed a bivalent vaccine containing formalin-inactivated A.veronii and E.ictaluri and evaluated the immune response in yellow catfish after immersion vaccination using body fluids biochemistry indices,agglutinating antibody titers,and the expression level of immune-related genes in the skin,gills,spleen,and head kidney.The activities of innate immune-related enzymes and specific agglutination antibody titers in body fluids,as well as the expression of innate and adaptive immune-related genes in both the mucosal and systemic tissues of vaccinated fish,were significantly higher than that in control fish.Next,we assessed the protective efficacy by a challenge model of virulent strains of E.ictaluri and A.veronii.The relative survival percent of vaccinated fish was 80%and 87%after challenging fish with E.ictaluri and A.veronii,respectively,which was higher than unvaccinated control fish(43%and 57%).These results confirm that the bivalent inactivated vaccine administered via immersion induces a strong mucosal immune response and confers good protection against both E.ictaluri and A.veronii.Our results also reinforce the notion that immersion vaccination could stimulate both mucosal and systemic immunity contributing to protection against pathogens.
基金supported by the National Natural Science Foundation of China (31672635)China Agricultural Research System (CARS-46)
文摘The sex-determining genes are found to be variable among different fish species. Yellow catfish(Pelteobagrus fulvidraco) is an important aquaculture fish species in China with XX/XY sex-determining type. Recently, YY super-male yellow catfish has been successfully produced by combining hormonalinduced sex reversal method with sex chromosome-linked markers. Here, we identified a novel PDZ domain-containing gene in yellow catfish designated as pfpdz1, in whose intron the sex-linked marker was located. The coding sequence of pfpdz1 in Y chromosome was identical to that in X chromosome except a missense SNP(A/T) that changes an amino acid(E8V) in the N-terminal region. Pfpdz1 displayed male-specific expression during sex differentiation. Overexpression of pfpdz1 using additive transgenesis induces XX ovary to differentiate into testis-like tissue, while the targeted inactivation of pfpdz1 in Y chromosome using CRISPR/Cas9-mediated mutagenesis triggers ovarian differentiation. Furthermore,we demonstrated that pfpdz1 initiates testicular differentiation through upregulating expression of amh, dmrt1 and sox9a1, as well as downregulating expression of cyp19a1, foxl2 and wnt4. Our data provide functional evidence that pfpdz1 is significant for male differentiation and maintenance in yellow catfish.
基金financially supported by the National Natural Science Foundation of China (31702362)the Applied Basic Research Programs of Science and Technology Commission Foundation of Sichuan Province,China (grant number 2015JY0067).
文摘Mitogen-activated protein kinases(MAPK) and nuclear factor kappa B(NF-κB) pathways are considered to be two crucial intracellular signaling cascades in pro-inflammatory responses.In this study,we reported the coding sequences(CDS) of MAPKp38 and NF-κBp65 from yellow catfish.We also investigated the gene structure,expression patterns and functional role in yellow catfish.The CDS of MAPKp38 is1,086 bp encoding 361 amino acids(AA).The MAPKp38 protein has a long highly conserved serine/threonine protein kinases catalytic domain.The NF-κBp65 CDS is 1,794 bp,and the gene encodes 597 AA,with a Rel homology domain(RHD) which consists of a RHD-DNA-binding domain and an Ig-like,plexins,transcription factors(IPT) domain.Moreover,MAPKp38 and NF-κBp65 protein of bony fish and other vertebrates have a single clade.Quantitative real-time PCR analysis revealed the presence of the MAPKp38 and NF-κBp65 transcript in 12 tissues of healthy yellow catfish.The highest expression levels of MAPKp38 and NF-κBp65 were detected in the heart and liver,respectively.Upon stimulation with an intraperitoneal injection of lipopolysaccharide(LPS),the expression levels of MAPKp38 and NF-κBp65 were up-regulated in the intestine.These results indicated that MAPKp38 and NF-κBp65 play important roles in mediating the response protection against LPS in yellow catfish.
