To correctly assess and properly manage the public health risks associated with exposure to contaminated water,it is necessary to identify the source of fecal pollution in a watershed.In this study,we evaluated the ef...To correctly assess and properly manage the public health risks associated with exposure to contaminated water,it is necessary to identify the source of fecal pollution in a watershed.In this study,we evaluated the efficacy of our two previously developed real time-quantitative PCR(qPCR)assays for the detection of swine-associated Bacteroidales genetic markers(gene 1-38,gene 3-53)in the Yangtze Delta watershed of southeastern China.The results indicated that the gene 1-38 and 3-53 markers exhibited high accuracy(92.5%,91.7%conditional probability,respectively)in detecting Bacteroidales spp.in water samples.According to binary logistic regression(BLR),these two swine-associated markers were well correlated(P<0.05)with fecal indicators(Escherichia coli and Enterococci spp.)and zoonotic pathogens(E.coli O157:H7,Salmonella spp.and Campylobacter spp.)in water samples.In contrast,concentrations of conventional fecal indicator bacteria(FIB)were not correlated with zoonotic pathogens,suggesting that they are noneffective at detecting fecal pollution events.Collectively,the results obtained in this study demonstrated that a swinetargeted qPCR assay based on two Bacteroidales genes markers(gene 1-38,gene 3-53)could be a useful tool in determining the swine-associated impacts of fecal contamination in a watershed.展开更多
In China,pig feces is the predominant source of excrement produced b y animal husbandry.Improper use or direct discharge of pig feces can result in contamination of natural water systems.Microbial source tracking(MST)...In China,pig feces is the predominant source of excrement produced b y animal husbandry.Improper use or direct discharge of pig feces can result in contamination of natural water systems.Microbial source tracking(MST)technology can identify the sources of fecal pollution in environmental water,and contribute to the management of pig fecal pollution by local environmental protection agencies.However,the accuracy of such assays can be context-dependent,and they have not been comprehensively evaluated under Chinese conditions.We aimed to compare the performance of five previously reported nig-specific MST assays(PF,Pig-Bac 1 STBR,Pig-Bac2 SYBR,Pig-1-Bac TaqMan,and Pig-2-Bac TaqMan,which are based on Bacteroidales 16S rRNA gene markers)and apply them in two rivers of North China.We collected a total of 173 fecal samples from pigs,cows,goats,chickens,humans,and horses across China.The PF assay optimized in this study showed outstanding qualitative performance and achieved 100%specificity and sensitivity.However,the two SYBR green qPCR assays(Pig-Bac1 SYBR and Pig-Bac2 SYBR)cross-reacted with most non-pig fecal samples.In contrast,both the Pig-l-Bac TaqMan and Pig-2-Bacr TaqMan assays gave 100%specificity and sensitivity.Of these,the Pig-2-Bac TaqMan assay showed higher reproducibility.Our results regarding the specificity of these pig-specific MST assays differ from those reported in Thailand,Japan,and America.Using the PF and Pig-2-Bac TaqMan assays,a field test comparing the levels of pig fecal pollution in rivers near a pig farm before and after comprehensive environmental pollution governance indicated that pig fecal pollution was effectively controlled at this location.展开更多
The presence of Total coliform, Eschericha coli and enterococci were enumerated in the cattle farming areas of the Oconee Watershed using colilertTM and enterolertTM IDEXX plates, respectively. Microbial Source Tracki...The presence of Total coliform, Eschericha coli and enterococci were enumerated in the cattle farming areas of the Oconee Watershed using colilertTM and enterolertTM IDEXX plates, respectively. Microbial Source Tracking (MST) using Bacteroidales molecular markers for ruminant (RuBac) and human (HuBac) specific bacterial groups were used to determine the source of the fecal pollution in the watershed. In the cattle farming regions of the watershed higher levels of fecal bacteria were detected compared to the levels of fecal bacteria at the forested and residential sites. MST indicated that the cattle farming regions (except DC2) of the lake was impacted by fecal pollution from a ruminant source such as cattle. In addition, qPCR for the tuf gene of E. coli and the Stx2 gene that is commonly found in enterohemorragic E. coli O157:H7 were used to evaluate the presence of these bacteria in the study area. E. coli O157:H7 (Stx2 gene) was detected only in the beef cattle regions of the watershed. The presences of E. coli and Stx2 gene in the Oconee Watershed represent a potential public health risk because Lake Oconee and its tributaries are used for recreational activities as well as crop irrigation.展开更多
基金supported by the National Key Research and Development Program of China(No.2016YFD0501105)the Science and Technology Department of Zhejiang Province(No.2015C02044)the National Natural Science Foundation of China(No.31301492)
文摘To correctly assess and properly manage the public health risks associated with exposure to contaminated water,it is necessary to identify the source of fecal pollution in a watershed.In this study,we evaluated the efficacy of our two previously developed real time-quantitative PCR(qPCR)assays for the detection of swine-associated Bacteroidales genetic markers(gene 1-38,gene 3-53)in the Yangtze Delta watershed of southeastern China.The results indicated that the gene 1-38 and 3-53 markers exhibited high accuracy(92.5%,91.7%conditional probability,respectively)in detecting Bacteroidales spp.in water samples.According to binary logistic regression(BLR),these two swine-associated markers were well correlated(P<0.05)with fecal indicators(Escherichia coli and Enterococci spp.)and zoonotic pathogens(E.coli O157:H7,Salmonella spp.and Campylobacter spp.)in water samples.In contrast,concentrations of conventional fecal indicator bacteria(FIB)were not correlated with zoonotic pathogens,suggesting that they are noneffective at detecting fecal pollution events.Collectively,the results obtained in this study demonstrated that a swinetargeted qPCR assay based on two Bacteroidales genes markers(gene 1-38,gene 3-53)could be a useful tool in determining the swine-associated impacts of fecal contamination in a watershed.
基金This work was supported by the National Key Research and Development Program of China(No.2016YFC0503601)Excellent Young Teachers'Scientific Research Ability Improvement Project of University of Chinese Academy of Sciences(No.Y95401FXX2).
文摘In China,pig feces is the predominant source of excrement produced b y animal husbandry.Improper use or direct discharge of pig feces can result in contamination of natural water systems.Microbial source tracking(MST)technology can identify the sources of fecal pollution in environmental water,and contribute to the management of pig fecal pollution by local environmental protection agencies.However,the accuracy of such assays can be context-dependent,and they have not been comprehensively evaluated under Chinese conditions.We aimed to compare the performance of five previously reported nig-specific MST assays(PF,Pig-Bac 1 STBR,Pig-Bac2 SYBR,Pig-1-Bac TaqMan,and Pig-2-Bac TaqMan,which are based on Bacteroidales 16S rRNA gene markers)and apply them in two rivers of North China.We collected a total of 173 fecal samples from pigs,cows,goats,chickens,humans,and horses across China.The PF assay optimized in this study showed outstanding qualitative performance and achieved 100%specificity and sensitivity.However,the two SYBR green qPCR assays(Pig-Bac1 SYBR and Pig-Bac2 SYBR)cross-reacted with most non-pig fecal samples.In contrast,both the Pig-l-Bac TaqMan and Pig-2-Bacr TaqMan assays gave 100%specificity and sensitivity.Of these,the Pig-2-Bac TaqMan assay showed higher reproducibility.Our results regarding the specificity of these pig-specific MST assays differ from those reported in Thailand,Japan,and America.Using the PF and Pig-2-Bac TaqMan assays,a field test comparing the levels of pig fecal pollution in rivers near a pig farm before and after comprehensive environmental pollution governance indicated that pig fecal pollution was effectively controlled at this location.
文摘The presence of Total coliform, Eschericha coli and enterococci were enumerated in the cattle farming areas of the Oconee Watershed using colilertTM and enterolertTM IDEXX plates, respectively. Microbial Source Tracking (MST) using Bacteroidales molecular markers for ruminant (RuBac) and human (HuBac) specific bacterial groups were used to determine the source of the fecal pollution in the watershed. In the cattle farming regions of the watershed higher levels of fecal bacteria were detected compared to the levels of fecal bacteria at the forested and residential sites. MST indicated that the cattle farming regions (except DC2) of the lake was impacted by fecal pollution from a ruminant source such as cattle. In addition, qPCR for the tuf gene of E. coli and the Stx2 gene that is commonly found in enterohemorragic E. coli O157:H7 were used to evaluate the presence of these bacteria in the study area. E. coli O157:H7 (Stx2 gene) was detected only in the beef cattle regions of the watershed. The presences of E. coli and Stx2 gene in the Oconee Watershed represent a potential public health risk because Lake Oconee and its tributaries are used for recreational activities as well as crop irrigation.
