With excessive utilization of antibiotics in recent years,bacterial drug resistance problem is serious increasingly,and it is more and more difficult to develop anti-infective drug,while it does not have these problem...With excessive utilization of antibiotics in recent years,bacterial drug resistance problem is serious increasingly,and it is more and more difficult to develop anti-infective drug,while it does not have these problems to use phage controlling disease.Phage is a kind of prokaryotic virus,widely exists in the nature and includes bacteriophage,cyanophage and actinophage.Due to its potential of replacing antibiotics to treat disease,phage receives more and more attention.In this paper,based on development status of phage research at home and abroad,discovery process,naming method and classification basis of phage are introduced comprehensively,and advantages and limitations of phage applying in prevention and control of bacterial diseases are analyzed.We introduce application status of phage in human medicine,prevention and control of diseases for terrestrial animals and aquaculture,and the effects of phage in sewage treatment,prevention and control of microbial contamination of food and detection technology,and point out the shortages of phage in the above application.Meanwhile,we also discuss application prospects of phage in disease prevention and control,environmental protection and food safety.展开更多
Edwardsiella ictaluri is known as the etiological agent of Red-head disease of yellow catfish(Pelteobagrus fulvidraco),and is the cause of heavy economic losses in the aquaculture industry.In this study,a DotEnzyme Li...Edwardsiella ictaluri is known as the etiological agent of Red-head disease of yellow catfish(Pelteobagrus fulvidraco),and is the cause of heavy economic losses in the aquaculture industry.In this study,a DotEnzyme Linked Immunosorbent Assay(Dot-ELISA)and an Indirect Fluorescence Antibody technique(IFAT)for detecting Edwardsiella ictaluri were developed by using a monoclonal antibody,5D11.For DotELISA,the working dilutions of 5D11 and the secondary antisera(enzyme-labeled goat anti-mouse Ig)were 1:320 dilution and 1:3000 dilution,respectively.For IFAT,the working dilutions of 5D11 and goatanti-mouse Ig conjugated with fluorescein isothiocyanate were as respectively 1:80 and 1:256.Both of the methods established were highly sensitivity(Minimum detectable concentration,5107 CFU/mL)and had a high degree of accuracy(positive rate was 100%for both artificial infected fish and spontaneous diseased Pelteobagrus fulvidraco).The two reliable methods developed have high potential for quick and efficient detection of Edwardsiella ictaluri in aquaculture production units.展开更多
In this study,bacterial pathogens were isolated from the liver,spleen,kidney,heart,and muscle of diseased goldfish(Carassius auratus)after a massive outbreak of disease in an aquaculture farm in Anshan,Liaoning Provin...In this study,bacterial pathogens were isolated from the liver,spleen,kidney,heart,and muscle of diseased goldfish(Carassius auratus)after a massive outbreak of disease in an aquaculture farm in Anshan,Liaoning Province,North China(N41°05′58.42″E122°53′31.89″).Based on physiological and biochemical characterization of the bacteria and 16S rDNA sequence analysis,the bacterial isolates were identified as Aeromonas salmonicida salmonicida.Virulence gene multilocus sequence typing analysis showed that the bacterial isolates from all the organs collected were of the same type,and clustered in the same phylogenetic group as A.salmonicida salmonicida.The pathogen,was named AS.17 and was resistant to rifampicin,bacitracin,vancomycin,penicillin and compound sulfamethoxazole,but was highly sensitive to nalidixic acid,lomefloxacin,spectinomycin,ofloxacin,and ciprofloxacin.Goldfish experimentally infected with AS.17 had similar symptoms to naturally infected fish,including gill filament anemia,intestinal bleeding,intra-abdominal fluid,and jaw bleeding.Histological analyses showed that the liver,the spleen,the kidney and the intestines of fish infected with AS.17 had severe pathological alterations.In summary,this study reports the isolation of A.salmonicida salmonicida from C.auratus in North China and provides a reference strain and a research foundation for further studies on A.salmonicida disease control and epidemiology.展开更多
The Chinese herb Houttuynia cordata Thunb(abbreviated as HCT hereafter)has been widely used in human and livestock medical research.However,few studies have tested the effects of HCT in aquaculture systems,particularl...The Chinese herb Houttuynia cordata Thunb(abbreviated as HCT hereafter)has been widely used in human and livestock medical research.However,few studies have tested the effects of HCT in aquaculture systems,particularly in echinoderms.In this study,the impact of HCT was evaluated when used as a feed additive to enhance the immune response of the sea cucumber,Apostichopus japonicus.Two concentrations,1.5%and 3%,of HCT powder were tested by adding them to the feed.Feeding experiments had a four week duration and each week,the humoral and cellular immunity index of the intestine,tentacles,peristome,and coelomic fluid were analyzed.The results indicated that the percentage of A.japonicus coelomocytes significantly increased after supplementing feed with HCT,and reached a peak after one week of feeding with the 3%HCT supplementation.Analysis of reactive oxygen species(ROS)indicated that HCT in feed caused a notable increase in the coelomocyte ROS concentrations over the experimental period.In both the 1.5%and 3%HCT addition groups,the ROS peaked in the third week and then remained stable.In addition,alkaline phosphatase,acid phosphatase,superoxide dismutase,lysozyme activity of the intestine,tentacles,peristome and coelomic fluid were significantly improved during the four-week test period.In conclusion,1.5%and 3%HCT added to feed boosts the immune responses of A.japonicus.HCT has potential as an immune enhancer for mariculture of sea cucumbers.展开更多
基金Supported by Special Fund for Scientific Research in Marine Public Welfare Industry(201405003)
文摘With excessive utilization of antibiotics in recent years,bacterial drug resistance problem is serious increasingly,and it is more and more difficult to develop anti-infective drug,while it does not have these problems to use phage controlling disease.Phage is a kind of prokaryotic virus,widely exists in the nature and includes bacteriophage,cyanophage and actinophage.Due to its potential of replacing antibiotics to treat disease,phage receives more and more attention.In this paper,based on development status of phage research at home and abroad,discovery process,naming method and classification basis of phage are introduced comprehensively,and advantages and limitations of phage applying in prevention and control of bacterial diseases are analyzed.We introduce application status of phage in human medicine,prevention and control of diseases for terrestrial animals and aquaculture,and the effects of phage in sewage treatment,prevention and control of microbial contamination of food and detection technology,and point out the shortages of phage in the above application.Meanwhile,we also discuss application prospects of phage in disease prevention and control,environmental protection and food safety.
基金This study was supported by Public Science and Technology Research Funds Projects of Ocean(201405003)Cultivation Plan for Youth Agricultural Science and Technology Innovative Talents of Liaoning Province(2014003)+1 种基金Program of Liaoning Excellent Talents in University(LJQ2011075)to Prof.Qiang Li,General Scientific Research Project of Liaoning Education Department(L2015077)Doctoral Research Program of Liaoning Science and Technology Department(201601287)to Dr.Ruijun Li.
文摘Edwardsiella ictaluri is known as the etiological agent of Red-head disease of yellow catfish(Pelteobagrus fulvidraco),and is the cause of heavy economic losses in the aquaculture industry.In this study,a DotEnzyme Linked Immunosorbent Assay(Dot-ELISA)and an Indirect Fluorescence Antibody technique(IFAT)for detecting Edwardsiella ictaluri were developed by using a monoclonal antibody,5D11.For DotELISA,the working dilutions of 5D11 and the secondary antisera(enzyme-labeled goat anti-mouse Ig)were 1:320 dilution and 1:3000 dilution,respectively.For IFAT,the working dilutions of 5D11 and goatanti-mouse Ig conjugated with fluorescein isothiocyanate were as respectively 1:80 and 1:256.Both of the methods established were highly sensitivity(Minimum detectable concentration,5107 CFU/mL)and had a high degree of accuracy(positive rate was 100%for both artificial infected fish and spontaneous diseased Pelteobagrus fulvidraco).The two reliable methods developed have high potential for quick and efficient detection of Edwardsiella ictaluri in aquaculture production units.
基金funded in part by National Natural Science Foundation of China(41706177)Key Laboratory of Mariculture and Stock Enhancement in North China's Sea Open Project(2018-KF-17)Doctoral Research Project of Dalian Ocean University(HDYJ201617)to Dr.R.J.Li.
文摘In this study,bacterial pathogens were isolated from the liver,spleen,kidney,heart,and muscle of diseased goldfish(Carassius auratus)after a massive outbreak of disease in an aquaculture farm in Anshan,Liaoning Province,North China(N41°05′58.42″E122°53′31.89″).Based on physiological and biochemical characterization of the bacteria and 16S rDNA sequence analysis,the bacterial isolates were identified as Aeromonas salmonicida salmonicida.Virulence gene multilocus sequence typing analysis showed that the bacterial isolates from all the organs collected were of the same type,and clustered in the same phylogenetic group as A.salmonicida salmonicida.The pathogen,was named AS.17 and was resistant to rifampicin,bacitracin,vancomycin,penicillin and compound sulfamethoxazole,but was highly sensitive to nalidixic acid,lomefloxacin,spectinomycin,ofloxacin,and ciprofloxacin.Goldfish experimentally infected with AS.17 had similar symptoms to naturally infected fish,including gill filament anemia,intestinal bleeding,intra-abdominal fluid,and jaw bleeding.Histological analyses showed that the liver,the spleen,the kidney and the intestines of fish infected with AS.17 had severe pathological alterations.In summary,this study reports the isolation of A.salmonicida salmonicida from C.auratus in North China and provides a reference strain and a research foundation for further studies on A.salmonicida disease control and epidemiology.
基金This work was funded in part by the State Key Research Project"Marine environment safety"(2017YFC1404503)General Scientific Research Project of Education Department in Liaoning Province(L2015077)+1 种基金Doctoral Research Project of Science and Technology Department program in in Liaoning Province(201601287)Doctoral Research Project of Dalian Ocean University(HDYJ201617).
文摘The Chinese herb Houttuynia cordata Thunb(abbreviated as HCT hereafter)has been widely used in human and livestock medical research.However,few studies have tested the effects of HCT in aquaculture systems,particularly in echinoderms.In this study,the impact of HCT was evaluated when used as a feed additive to enhance the immune response of the sea cucumber,Apostichopus japonicus.Two concentrations,1.5%and 3%,of HCT powder were tested by adding them to the feed.Feeding experiments had a four week duration and each week,the humoral and cellular immunity index of the intestine,tentacles,peristome,and coelomic fluid were analyzed.The results indicated that the percentage of A.japonicus coelomocytes significantly increased after supplementing feed with HCT,and reached a peak after one week of feeding with the 3%HCT supplementation.Analysis of reactive oxygen species(ROS)indicated that HCT in feed caused a notable increase in the coelomocyte ROS concentrations over the experimental period.In both the 1.5%and 3%HCT addition groups,the ROS peaked in the third week and then remained stable.In addition,alkaline phosphatase,acid phosphatase,superoxide dismutase,lysozyme activity of the intestine,tentacles,peristome and coelomic fluid were significantly improved during the four-week test period.In conclusion,1.5%and 3%HCT added to feed boosts the immune responses of A.japonicus.HCT has potential as an immune enhancer for mariculture of sea cucumbers.