Enterotoxigenic Escherichio coli (ETEC) causes neonatal and post-weaning diarrhea in pigs. In order to determine the risk factors, rectal/fecal swabs and visceral organs obtained from pig farms in two regions of Sou...Enterotoxigenic Escherichio coli (ETEC) causes neonatal and post-weaning diarrhea in pigs. In order to determine the risk factors, rectal/fecal swabs and visceral organs obtained from pig farms in two regions of South Africa were analyzed microbiologically against risk variables. Seventy-two percent of young pigs were found to be positive for ETEC toxin genes; estB (38.9%), estB/STAP (25%), and estB/LT (13.9%) were dominant. Risk factors for ETEC-diarrhea in pigs include: leaving sick piglets in a pen with healthy piglets [odds ratio (OR) = 33.52; P 〈 0.0001]; water spillage in pen (OR = 42.87; P 〈 0.0001); hypothermic piglets (OR = 7.29; P 〈 0.0001); runt piglets in pen with healthy littermates (OR = 3.65; P 〈 0.0001); and prolonged use of antibiotics (OR = 3.05; P = 0.05).展开更多
Background:This study aimed to investigate the effects of oral administration of Enterococcus faecium NCIMB10415(E.faecium)on intestinal development,immunological parameters and gut microbiota of neonatal piglets chal...Background:This study aimed to investigate the effects of oral administration of Enterococcus faecium NCIMB10415(E.faecium)on intestinal development,immunological parameters and gut microbiota of neonatal piglets challenged with enterotoxigenic Escherichia coli K88(ETEC).A total of 961-day-old sow-reared piglets were randomly assigned to 2 groups,with 48 piglets in each group.The piglets were from 16 litters(6 piglets each litter),and 3 piglets each litter were allocated to the E.faecium-supplemented(PRO)group,while the other 3 piglets were allocated to the control(CON)group.After colostrum intake,piglets in the PRO group were orally administrated with 3×10~9 CFU E.faecium per day for a period of one week.On day 8,one piglet per litter from each group was challenged(CON+ETEC,PRO+ETEC)or not(CON-ETEC,PRO-ETEC)with ETEC in a 2×2 factorial arrangement of treatments.On day 10(2 days after challenge),blood and tissue samples were obtained from piglets.Results:Before ETEC challenge,there were no significant differences for the average daily gain(ADG)and fecal score between the two groups of piglets.After ETEC challenge,the challenged piglets had greater fecal score compared to the non-challenged piglets,whereas E.faecium administration was able to decrease the fecal score.Piglets challenged with ETEC had shorter villous height,deeper crypt depth,and reduced number of goblet cells in the jejunum and decreased m RNA abundance of claudin-1 in the ileum,whereas increased the percentage of lymphocytes,concentrations of IL-1βin the plasma and TNF-αin the ileal mucosa,as well as increased the m RNA abundances of innate immunity-related genes in the ileum tissue.These deleterious effects caused by ETEC were partly alleviated by feeding E.faecium.In addition,piglets in PRO-ETEC group had decreased the percentage of CD8^+T cells of the peripheral blood when compared to those in CON-ETEC group.Moreover,E.faecium administration increased Verrucomicrobia at phylum level and decreased Bilophila at genus level.Conclusions:These results suggest that oral administration of E.faecium alleviated the intestinal injury and diarrhea severity of neonatal piglets challenged by ETEC,partly through improving the intestinal microbiota and immune response.This offers a potential strategy of dietary intervention against intestinal impairment by ETEC in neonatal piglets.展开更多
The gene cluster cfaABCED’ of enterotoxigenic Escherichia coli, encoding the fimbriae which is called colonization factor antigen located on a plasmid. It is positively regulated by cfaR, a member of the AraC family,...The gene cluster cfaABCED’ of enterotoxigenic Escherichia coli, encoding the fimbriae which is called colonization factor antigen located on a plasmid. It is positively regulated by cfaR, a member of the AraC family, and the cfaD’ gene region, which is located downstream of cfaE and is homologous to cfaR, had been described as a truncated cryptic gene. In the present study we observed that the CFA/ fimbriae subunit, cfaB, was expressed in lower amount by the cfaABCED’ clone pNTP513 in host E. coli HB101. The expression of CFA/ diminished by deletion of cfaD’ gene region from pNTP513, and was restored by acquisition of cfaD’ in trans. Furthermore, CFA/ expression by cfaD’ deletion mutant, the cfaABCE clone, was remarkably increased by the presence of cfaD’ in trans in a topoisomerase A deficient strain of E. coli DM800. These data suggest that cfaD’ region is a functional region of gene, that regulates the CFA/ expression with cfaR by unknown mechanism.展开更多
Alternatives to antibiotics for preventing bacteria-induced inflammation in early-weaned farm animals are sorely needed. Our previous study showed that Lactiplantibacillus plantarum L47 and inulin could alleviate dext...Alternatives to antibiotics for preventing bacteria-induced inflammation in early-weaned farm animals are sorely needed. Our previous study showed that Lactiplantibacillus plantarum L47 and inulin could alleviate dextran sulfate sodium(DSS)-induced colitis in mice. To explore the protective effects of L. plantarum L47 and inulin on the ileal inflammatory response in weaned piglets challenged with enterotoxigenic Escherichia coli(ETEC), 28 weaned piglets were assigned into four groups, namely, CON group—orally given 10 mL/d phosphate buffer saline(PBS), LI47 group—orally given a mixture of 10 m L/d L. plantarum L47 and inulin, ECON group—orally given 10 mL/d PBS and challenged by ETEC, and ELI47group—orally given 10 mL/d L. plantarum L47 and inulin mixture and challenged by ETEC. The results demonstrated that the combination of L. plantarum L47 and inulin reduced inflammatory responses and relieved the inflammatory damage caused by ETEC, including ileal morphological damage, reduced protein expression of ileal tight junction, decreased antioxidant capacity, and decreased antiinflammatory factors. Transcriptome analysis revealed that L. plantarum L47 and inulin up-regulated the gene expression of phospholipase A2 group IIA(PLA2G2A)(P < 0.05) as well as affected alphalinolenic acid(ALA) metabolism and linoleic acid metabolism. Moreover, L. plantarum L47 and inulin increased the levels of ALA(P < 0.05), lipoteichoic acid(LTA)(P < 0.05), and 12,13-epoxyoctadecenoic acid(12,13-EpOME)(P < 0.05) and the protein expression of Toll-like receptor 2(TLR2)(P = 0.05) in the ileal mucosa. In conclusion, L. plantarum L47 and inulin together alleviated ETEC-induced ileal inflammation in piglets by up-regulating the levels of ALA and 12,13-EpOME via the LTA/TLR2/PLA2G2A pathway.展开更多
A multiplex polymerase chain reaction (PCR) was developed to detect three pathogenic genes of enteropathogenic, enterotocigenic and enteroinvasive Escherichia coli In this study three different sets of oligonucleoti...A multiplex polymerase chain reaction (PCR) was developed to detect three pathogenic genes of enteropathogenic, enterotocigenic and enteroinvasive Escherichia coli In this study three different sets of oligonucleotide primer were simultaneously used, and in this way, specific fragments of 880, 600, 150 bp for EPEC eaeA, EIEC ipaH and ETEC ST genes were amplified, respectively. The best condition of the multiplex PCR was: after an initial heat denaturation step at 95℃for 5 min, followed by 30 cycles of denaturation at 94 ℃ for 40 s, primer annealing at 51.3℃ for 40 s and extension at 72 ℃ for 1 min, final extension at 72 ℃ for 10 min. The detection limit of the eaeA, ipaH and ST primers was 38.7423, 3.60519, 29.9448 ng·mL^-1 (4.3×10^4, 1.5×10^3, 2.6×10^4 CFU·mL^-1), respectively. It may be a good way for the detection and identification of Diarrhea-causing E. coli.展开更多
Background:Our previous study has shown that supplementation of trace amounts of antibiotic exacerbated the detrimental effects of enterotoxigenic E.coli(ETEC)infection and delayed the recovery of pigs that may be ass...Background:Our previous study has shown that supplementation of trace amounts of antibiotic exacerbated the detrimental effects of enterotoxigenic E.coli(ETEC)infection and delayed the recovery of pigs that may be associated with modified metabolites and metabolic pathways.Therefore,the objective of this study was to explore the impacts of trace levels of antibiotic(carbadox)on host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC F18.Results:The multivariate analysis highlighted a distinct metabolomic profile of serum and colon digesta between trace amounts of antibiotic(TRA;0.5 mg/kg carbadox)and label-recommended dose antibiotic(REC;50 mg/kg carbadox)on d 5 post-inoculation(PI).The relative abundance of metabolomic markers of amino acids,carbohydrates,and purine metabolism were significantly differentiated between the TRA and REC groups(q<0.2).In addition,pigs in REC group had the highest(P<0.05)relative abundance of Lactobacillaceae and tended to have increased(P<0.10)relative abundance of Lachnospiraceae in the colon digesta on d 5 PI.On d 11 PI,pigs in REC had greater(P<0.05)relative abundance of Clostridiaceae compared with other groups,whereas had reduced(P<0.05)relative abundance of Prevotellaceae than pigs in control group.Conclusions:Trace amounts of antibiotic resulted in differential metabolites and metabolic pathways that may be associated with its slow responses against ETEC F18 infection.The altered gut microbiota profiles by labelrecommended dose antibiotic may contribute to the promotion of disease resistance in weaned pigs.展开更多
文摘Enterotoxigenic Escherichio coli (ETEC) causes neonatal and post-weaning diarrhea in pigs. In order to determine the risk factors, rectal/fecal swabs and visceral organs obtained from pig farms in two regions of South Africa were analyzed microbiologically against risk variables. Seventy-two percent of young pigs were found to be positive for ETEC toxin genes; estB (38.9%), estB/STAP (25%), and estB/LT (13.9%) were dominant. Risk factors for ETEC-diarrhea in pigs include: leaving sick piglets in a pen with healthy piglets [odds ratio (OR) = 33.52; P 〈 0.0001]; water spillage in pen (OR = 42.87; P 〈 0.0001); hypothermic piglets (OR = 7.29; P 〈 0.0001); runt piglets in pen with healthy littermates (OR = 3.65; P 〈 0.0001); and prolonged use of antibiotics (OR = 3.05; P = 0.05).
基金supported by the Projects of The National Key Research and Development Program of China(grant number 2016YFD0501204)Sichuan provincial project on S&T application and demonstration(grant number2016CC0070)the project on commercialization of research findings under funding of government of Sichuan province(grant number16ZHSF0385).
文摘Background:This study aimed to investigate the effects of oral administration of Enterococcus faecium NCIMB10415(E.faecium)on intestinal development,immunological parameters and gut microbiota of neonatal piglets challenged with enterotoxigenic Escherichia coli K88(ETEC).A total of 961-day-old sow-reared piglets were randomly assigned to 2 groups,with 48 piglets in each group.The piglets were from 16 litters(6 piglets each litter),and 3 piglets each litter were allocated to the E.faecium-supplemented(PRO)group,while the other 3 piglets were allocated to the control(CON)group.After colostrum intake,piglets in the PRO group were orally administrated with 3×10~9 CFU E.faecium per day for a period of one week.On day 8,one piglet per litter from each group was challenged(CON+ETEC,PRO+ETEC)or not(CON-ETEC,PRO-ETEC)with ETEC in a 2×2 factorial arrangement of treatments.On day 10(2 days after challenge),blood and tissue samples were obtained from piglets.Results:Before ETEC challenge,there were no significant differences for the average daily gain(ADG)and fecal score between the two groups of piglets.After ETEC challenge,the challenged piglets had greater fecal score compared to the non-challenged piglets,whereas E.faecium administration was able to decrease the fecal score.Piglets challenged with ETEC had shorter villous height,deeper crypt depth,and reduced number of goblet cells in the jejunum and decreased m RNA abundance of claudin-1 in the ileum,whereas increased the percentage of lymphocytes,concentrations of IL-1βin the plasma and TNF-αin the ileal mucosa,as well as increased the m RNA abundances of innate immunity-related genes in the ileum tissue.These deleterious effects caused by ETEC were partly alleviated by feeding E.faecium.In addition,piglets in PRO-ETEC group had decreased the percentage of CD8^+T cells of the peripheral blood when compared to those in CON-ETEC group.Moreover,E.faecium administration increased Verrucomicrobia at phylum level and decreased Bilophila at genus level.Conclusions:These results suggest that oral administration of E.faecium alleviated the intestinal injury and diarrhea severity of neonatal piglets challenged by ETEC,partly through improving the intestinal microbiota and immune response.This offers a potential strategy of dietary intervention against intestinal impairment by ETEC in neonatal piglets.
文摘The gene cluster cfaABCED’ of enterotoxigenic Escherichia coli, encoding the fimbriae which is called colonization factor antigen located on a plasmid. It is positively regulated by cfaR, a member of the AraC family, and the cfaD’ gene region, which is located downstream of cfaE and is homologous to cfaR, had been described as a truncated cryptic gene. In the present study we observed that the CFA/ fimbriae subunit, cfaB, was expressed in lower amount by the cfaABCED’ clone pNTP513 in host E. coli HB101. The expression of CFA/ diminished by deletion of cfaD’ gene region from pNTP513, and was restored by acquisition of cfaD’ in trans. Furthermore, CFA/ expression by cfaD’ deletion mutant, the cfaABCE clone, was remarkably increased by the presence of cfaD’ in trans in a topoisomerase A deficient strain of E. coli DM800. These data suggest that cfaD’ region is a functional region of gene, that regulates the CFA/ expression with cfaR by unknown mechanism.
基金National Key Research and Development Program of China (2021YFD1300301-5)。
文摘Alternatives to antibiotics for preventing bacteria-induced inflammation in early-weaned farm animals are sorely needed. Our previous study showed that Lactiplantibacillus plantarum L47 and inulin could alleviate dextran sulfate sodium(DSS)-induced colitis in mice. To explore the protective effects of L. plantarum L47 and inulin on the ileal inflammatory response in weaned piglets challenged with enterotoxigenic Escherichia coli(ETEC), 28 weaned piglets were assigned into four groups, namely, CON group—orally given 10 mL/d phosphate buffer saline(PBS), LI47 group—orally given a mixture of 10 m L/d L. plantarum L47 and inulin, ECON group—orally given 10 mL/d PBS and challenged by ETEC, and ELI47group—orally given 10 mL/d L. plantarum L47 and inulin mixture and challenged by ETEC. The results demonstrated that the combination of L. plantarum L47 and inulin reduced inflammatory responses and relieved the inflammatory damage caused by ETEC, including ileal morphological damage, reduced protein expression of ileal tight junction, decreased antioxidant capacity, and decreased antiinflammatory factors. Transcriptome analysis revealed that L. plantarum L47 and inulin up-regulated the gene expression of phospholipase A2 group IIA(PLA2G2A)(P < 0.05) as well as affected alphalinolenic acid(ALA) metabolism and linoleic acid metabolism. Moreover, L. plantarum L47 and inulin increased the levels of ALA(P < 0.05), lipoteichoic acid(LTA)(P < 0.05), and 12,13-epoxyoctadecenoic acid(12,13-EpOME)(P < 0.05) and the protein expression of Toll-like receptor 2(TLR2)(P = 0.05) in the ileal mucosa. In conclusion, L. plantarum L47 and inulin together alleviated ETEC-induced ileal inflammation in piglets by up-regulating the levels of ALA and 12,13-EpOME via the LTA/TLR2/PLA2G2A pathway.
基金Key Item of National Technology Research Project (2002BA518A06)Heilongjiang Province Department Fund (10541021)
文摘A multiplex polymerase chain reaction (PCR) was developed to detect three pathogenic genes of enteropathogenic, enterotocigenic and enteroinvasive Escherichia coli In this study three different sets of oligonucleotide primer were simultaneously used, and in this way, specific fragments of 880, 600, 150 bp for EPEC eaeA, EIEC ipaH and ETEC ST genes were amplified, respectively. The best condition of the multiplex PCR was: after an initial heat denaturation step at 95℃for 5 min, followed by 30 cycles of denaturation at 94 ℃ for 40 s, primer annealing at 51.3℃ for 40 s and extension at 72 ℃ for 1 min, final extension at 72 ℃ for 10 min. The detection limit of the eaeA, ipaH and ST primers was 38.7423, 3.60519, 29.9448 ng·mL^-1 (4.3×10^4, 1.5×10^3, 2.6×10^4 CFU·mL^-1), respectively. It may be a good way for the detection and identification of Diarrhea-causing E. coli.
基金supported by the United States Department of Agriculture(USDA)National Institute of Food and Agriculture(NIFA),multistate projects W4002 and NC1202.
文摘Background:Our previous study has shown that supplementation of trace amounts of antibiotic exacerbated the detrimental effects of enterotoxigenic E.coli(ETEC)infection and delayed the recovery of pigs that may be associated with modified metabolites and metabolic pathways.Therefore,the objective of this study was to explore the impacts of trace levels of antibiotic(carbadox)on host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC F18.Results:The multivariate analysis highlighted a distinct metabolomic profile of serum and colon digesta between trace amounts of antibiotic(TRA;0.5 mg/kg carbadox)and label-recommended dose antibiotic(REC;50 mg/kg carbadox)on d 5 post-inoculation(PI).The relative abundance of metabolomic markers of amino acids,carbohydrates,and purine metabolism were significantly differentiated between the TRA and REC groups(q<0.2).In addition,pigs in REC group had the highest(P<0.05)relative abundance of Lactobacillaceae and tended to have increased(P<0.10)relative abundance of Lachnospiraceae in the colon digesta on d 5 PI.On d 11 PI,pigs in REC had greater(P<0.05)relative abundance of Clostridiaceae compared with other groups,whereas had reduced(P<0.05)relative abundance of Prevotellaceae than pigs in control group.Conclusions:Trace amounts of antibiotic resulted in differential metabolites and metabolic pathways that may be associated with its slow responses against ETEC F18 infection.The altered gut microbiota profiles by labelrecommended dose antibiotic may contribute to the promotion of disease resistance in weaned pigs.