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1.
《Veterinary microbiology》1997,54(2):133-144
Enterotoxigenic (ETEC) and enterotoxaemic (ETEEC) Escherichia (E.) coli that express F18 (F107) fimbriae colonize the small intestine and cause diarrhoea and/or oedema disease in weaned pigs. So far, two antigenic variants of F18 can be distinguished with a common antigenic factor designated ‘a’ and two specific factors called ‘b’ and ‘c’. In this study the existence of crosswise anti-colonization immunity between E. coli strains that express F18ab or F18ac fimbrial variants, respectively, was demonstrated. Weaned pigs of susceptible genotype with respect to susceptibility to adhesion of E. coli with fimbriae F18 were inoculated with E. coli strains 3064STM (O157:K-:H-:F18ab; resistant to streptomycin) and 8199RIF (O141ab:K-:H4:F18ac; resistant to rifampicin). The faecal shedding was compared subsequent to immunization and homologous or heterologous challenge. An enzyme-linked immunosorbent assay (ELISA) was applied to measure IgA, IgM and IgG antibodies against the F18ab and F18ac antigens in saliva, faeces, serum and intestinal wash samples. About 8 log CFU/g of the inoculated strains were found in faeces of all pigs following immunization as well as in non-immunized controls after challenge. Bacterial counts of the inoculated strains after challenge were between 2 and 5 log lower, without any difference between homologous and heterologous challenge. Intestinal colonization with fimbriated E. coli resulted in production of significantly increased levels of anti-fimbrial antibodies, especially IgA, in serum and intestinal wash samples. There were higher levels of homologous than of heterologous anti-fimbrial antibodies. Production of antibodies against F18a or against another common fimbrial antigen is probably responsible for crosswise anti-colonization immunity between E. coli strains with F18ab and F18ac fimbrial variants. Serum F18-specific IgA may be a useful indicator of a mucosal immune response directed against F18 fimbriae.  相似文献   

2.
Salmonella Typhimurium ghost cells expressing K88ab, K88ac, K99, and FasA fimbriae of enterotoxigenic Escherichia coli (ETEC) in their envelopes were constructed. The genes encoding the fimbriae were individually cloned into an expression plasmid, pMMP81, carrying the asd gene, which was subsequently electroporated into the Δasd S. Typhimurium mutant. Plasmid pJHLP99, carrying the phiX174 lysis gene E, was also subsequently electroporated into the Salmonella mutant. The presence of the individual fimbriae on the ghost cells was examined by Western blot analysis. Forty BALB/c mice were equally divided into 2 groups of 20 mice each. Group A mice were intramuscularly vaccinated with a mixture of the 4 ghost cells expressing the individual fimbriae. The group B mice were inoculated with sterile phosphate-buffered saline as a control. The antigen-specific serum IgG concentrations were significantly higher in group A than in group B from week 2 until week 6 after inoculation. In addition, the antigen-specific IgA concentrations in fecal samples were significantly higher in group A than in group B at week 2 after inoculation. A large difference between the groups in the number of antigen-specific IgA-secreting cells in the small intestine was observed by immunohistochemical study. Also, the splenic lymphocyte proliferative responses were significantly greater in group A than in the control mice. These results suggest that vaccination with our Salmonella ghost cells can induce both humoral and cell-mediated immune responses and that the increased number of antigen-specific IgA-secreting cells in the small intestine may be correlated with the elevated fecal IgA immune response.  相似文献   

3.
Escherichia coli adhesion assays were conducted using isolated porcine peripheral blood lymphocytes, Peyer's patch lymphocytes, rectal epithelial cells or brush borders, buccal epithelial cells and brush borders from small intestinal epithelial cells. The cells and brush borders were tested for their ability to bind K88-piliated exterotoxigenic E. coliStrain M1823B (K88ac) and E. coli Strain 1476 (K-12, K88ac). Comparison of adhesive phenotypes of 37 weaned pigs as determined by the adhesion assay with small intestinal brush borders and the adherence of K88ac+ enterotoxigenic E. coli to peripheral blood lymphocytes, Peyer's patch lymphocytes and rectal epithelial cells or brush borders, revealed no correlation. In vitro adhesion of K88ac-bearing E. coli was always negative with buccal epithelial cells. K88ac strains varied in their ability to adhere to lymphocytes and rectale pithelial cells or brush borders, indicating that the mechanism of adherence is unrelated to K88-mediated adhesion observed in animals that had the receptors on small-intestinal epithelial-cell brush borders. The non-piliated control E. coli Strain 123 adhered to fresh peripheral blood lymphocytes, and less intensively to frozen-thawed peripheral blood lymphocytes or Peyer's patch lymphocytes. It was concluded that none of the cell types or brush borders, except small-intestinal epithelial-cell brush borders, could be used as targets for phenotyping pigs for the presence of the K88 receptors that have been associated with adhesion and colonization of K88+ enterotoxigenic E. coli in the porcine small intestine.  相似文献   

4.
《Veterinary microbiology》1986,11(3):271-283
Escherichia coli colonies isolated from 50 diarrhoeic and 29 healthy piglets were investigated for several properties related to pathogenicity, such as production of heat-labile (LT) and heat-stable (STa) enterotoxins, presence of K88 and K99 colonization antigens, mannose-resistant haemagglutinating activity (MRHA), β-haemolysis and antibiotic resistance. The objective was to establish the toxic and adhesive abilities of E. coli strains that cause porcine diarrhoea in Galician farms. Fifty-seven colonies from 14 diarrhoeic piglets formed STa, while no STa+ colony was detected from healty piglets. Thirty-four of the 57 STa+ colonies were resistant to gentamicin. Sixteen representative STa+ strains isolated from the 14 infected piglets were serotyped, investigated for plasmid content and examined by electron microscopy. Of these STa+ strains, 15 belonged to serotype 0141:K85ab and carried on their surface the fimbrial antigen P987. The remaining representative STa+ strain belonged to serotype 0101:K30 and was K99+, being the only STa+ strain with MRHA activity. All 15 STa+ P987+ strains possessed a similar plasmid pattern, with three plasmids ranging in molecular weight from 33 × 106 to 74 × 106; nine of the gentamicin-resistant strains possessed an additional plasmid of molecular weight 16 × 106, which was absent in the six gentamicin-sensitive strains. Strains producing LT or K88 antigen were not detected. Forty-one MRHA+ colonies were isolated at similar rates from both diarrhoeic and healthy piglets. Twelve of the 19 non-enterotoxigenic MRHA+ strains of which the O-group was established, belonged to serogroups (01, 02, 07, 08, 09 and 075) typical of the human E. coli strains that cause extraintestinal infections. Finally, a statistically significant association between haemolytic and MRHA activities in porcine E. coli was found. In conclusion, it was found that STa+E. coli strains belonging to serotype 0141:K85ab:P987 are associated with porcine diarrhoea in Galicia. Additionally, no correlation between the isolation of non-ETEC MRHA+ strains and diarrhoea was observed.  相似文献   

5.
The OK antigens and the fimbriae F4 of E. coli with haemolysis isolated from 113 cases of oedema disease and/or diarrhoea were identified serologically. The genes for F18 and for enterotoxins LT, STIa and STII as well as Shigatoxin Stx2e were determined by PCR. Fimbrial variants F18ab and F18ac were distinguished by means of indirect immunofluorescence on smears prepared from the intestinal mucosa and from cultures grown under appropriate conditions. Adhesive fimbriae were detected with every case or isolate, respectively, by means of at least one out of the techniques mentioned above. The serogroup O149:K91 with fimbriae F4ac (K88ac) and genes for the enterotoxins LT and STII was most prevalent. Serogroup O139:K12 with fimbriae F18ab and the gene for Stx2e was second, whereas serogroups O141ab and O141ac with fimbriae F18ac and genes for Stx2e, STII and often LT were much less prevalent. The serogroup O147:K89 with fimbriae F18ac, and genes for STIa and STII was detected for the first time in Switzerland.  相似文献   

6.
An Escherichia coli strain (SEPT13) isolated from the liver of a hen presenting clinical signs of septicaemia had a LD50 of 4.0 × 105 CFU/ml in one-day-old chickens, expressed Ia, Ib, E1, E3, K and B colicins and aerobactin. The strain was ampicillin and streptomycin resistant, and found to have fimA, csgA and tsh DNA related sequences; it could adhere to and invade HEp-2 and tracheal epithelial cells, expressed fimbriae (observed by electron microscopy), and had five plasmids of 2.7, 4.7, 43, 56, and 88 MDa. Transposon mutagenesis of strain SEPT13, with transposon TnphoA, resulted in a mutant strain named ST16 that had a LD50 of 1.2 × 1012 CFU/ml. All other biological characteristics of strain ST16 were the same as those detected for strain SEPT13 except for the migration of an 88 MDa plasmid to the 93 MDa position indicating the insertion of the transposon into the 88 MDa plasmid. The 93 MDa plasmid of strain ST16 was transferred, by electroporation assay, to non-pathogenic receptor strains (E. coli strains K12 MS101 and HB101), resulting in transformant strains A and B, respectively. These strains exhibited adhesion properties to in vitro cultivated HEp-2 cells but did not have the capacity for invasion. The adherence occurred despite the absence of fimbriae; this finding suggests that the 88 MDa plasmid has afimbrial adhesin genes.  相似文献   

7.
The phenotype of 21 weaned piglets, concerning adhesion of Escherichia coli possessing K88ab, K88ac or K88ad fimbriae to pig cells, was determined in an in vitro assay. Comparison was made with adhesion of these three K88 variant strains to buccal mucosal epithelial cells and to erythrocytes (haemagglutination) in the same piglets. Whereas adhesion of the three K88 variant strains to intestinal villi was piglet specific, buccal cell adhesion (BCA) and haemagglutination (HA) were not. The K88ab strain was weakly adhesive or non-adhesive in the BCA and negative in the HA test. K88ac strains consistently gave negative and K88ad consistently gave positive results in both assays. After washing the bacteria with phosphate-buffered saline, the K88ab strain revealed a positive HA test. Neither the BCA, nor HA test can be used to determine the pig intestinal adhesive phenotype.  相似文献   

8.
The efficacy of a new vaccine against neonatal Escherichia coli diarrhoea in piglets containing purified F4ab, F4ac, F5 and F6 fimbriae and detoxified heat‐labile toxin (LT) was tested in challenge experiments by the method described by the European Pharmacopoeia (3rd edn, EDQM, Council of Europe, Strasbourg, France). A group of 11 young sows from a herd without E. coli problems was vaccinated 6–8 and 2–4 weeks prior to expected farrowing and another group of nine young sows were non‐vaccinated controls. Escherichia coli antibody titres were determined in serum samples taken from the sows before first vaccination and before farrowing and in colostrum samples. The newborn piglets were allowed to suckle colostrum from their mother immediately after birth. The piglets were marked with individually numbered ear tags. Approximately 12 h after birth, 118 piglets from vaccinated sows and 79 piglets from non‐vaccinated control sows were challenged by oral instillation of 5 ml of a freshly prepared culture of one of the challenge strains [O8:K87:F4ab (LT+) or O149:K91:F4ac (LT+) or O9:K30:F5 or O9:K103:F6 respectively]. The challenge cultures contained as a mean 6.8 × 109 CFU/ml. After challenge the piglets were observed for 7 days and mortality and morbidity were recorded. Vaccinated sows developed significant levels of antibody titres in colostrum and serum. Control sows stayed at a low/seronegative level. The protective efficacy was excellent because 66.7–87.5% of the piglets from vaccinated sows remained without clinical signs after challenge. Only 0.0–28.0% of the piglets from non‐vaccinated sows remained healthy and more than 47.1% of the piglets in this group died after challenge. It is concluded that the new vaccine is very effective in protection of piglets against neonatal E. coli diarrhoea.  相似文献   

9.
Iscom (immunostimulating complex) vaccines were prepared to contain K88ab, K88ac, K99 and 987P pili (fimbriae) of enterotoxigenic E. coli bacteria as monovalent or quadrivalent preparations. The iscoms injected into rabbits and into pigs elicited similar or higher immune response in both animal species than the oil adjuvanted vaccine containing about 5 times more of the same pilus protein. It is concluded that inclusion of pili into iscoms results in immunogenic preparations likely worth pursuing for vaccine production against enterotoxic colibacillosis of newborn pigs. The iscoms did not induce local reaction at the injection sites in contrast to the oil adjuvanted vaccines.  相似文献   

10.
In order to construct a novel vaccine candidate for preventing post-weaning diarrhea in swine, the individual genes for Escherichia coli K88ab, K88ac, FedA, and FedF fimbriae were inserted into a secretion plasmid pBP244 containing asd, lepB, secA, and secB. These were transformed into Salmonella Typhimurium Δlon ΔcpxR Δasd. Secretion of the individual recombinant fimbrial antigens was confirmed by immunoblot analysis. Groups 1 and 2 mice received a single oral dose of the vaccine mixture and S. Typhimurium carrying pBP244 only as a control, respectively. In groups 3 and 4, mice were primed and boosted with the vaccine mixture and S. Typhimurium carrying pBP244 only as a control, respectively. In general, all immunized mice had significantly increased serum immunoglobulin (Ig)G (P < 0.05) and intestinal secretory IgA against the individual fimbrial antigens compared with those mice in the control group. In the IgG2a and IgG1 titer assay, only IgG2a titer was increased in group 1, while both IgG2a and IgG1 titers were increased in group 3. Furthermore, the vaccine strains were not detected in the excreted feces of any immunized mice. Thus, the vaccine candidate can be highly immunogenic and be safe to the environment.  相似文献   

11.
检测K88~+肠毒素性大肠杆菌PCR方法的建立   总被引：5，自引：0，他引：5  
以K8 8菌毛结构基因保守序列为靶序列 ,设计合成了一对可扩增长 2 0 1bp的目的片段的引物 ,成功地建立了检测肠毒素性大肠杆菌(ETEC)K88菌毛基因的PCR方法。进行了PCR方法的特异性试验和敏感性试验。对K99+ ,F41 + ,987p+ 参考菌株和鼠伤寒沙门氏杆菌 ,链球菌 ,金黄色葡萄球菌和猪肺疫巴氏杆菌的检测结果均为阴性 ;该检测方法的敏感度可达 1 0个细菌。用此方法对 1 0株腹泻仔猪粪便分离物进行检测 ,结果有 2株阳性 ;与血清学检测的结果一致。结果表明此方法特异性和敏感性都很高 ,可用于临床K88+ 肠毒素性大肠杆菌病的快速诊断和流行病学调查  相似文献   

12.
The aim of the study was to compare the resistance patterns of Escherichia coli isolates from pig herds with or without prophylactic use of anti‐microbial substances. The presented pig units received either antibiotics or oregano as preventive feed additives. The trial was performed from April to October 2001, in the large ‘country‐corner’, Hungary–Rumania–Serbia. Thirty of 39 evaluated herds suffered E. coli O139 K88 ac or ad LT STb caused losses, the remaining were negative for E. coli O139. Thirteen of the selected 30 herds produced with oregano feed supplementation (Oregpig® Pecs, Hungary) antibiotic‐free pigs. These units had no history of prophylactic antibiotic use since 1995. The remaining 17 herds routinely used prophylactic antibiotic feed supplementation. In each herd, pigs of four different age groups (suckling piglets, weaners, fattening swine and breeding sows), showing the clinical symptoms of wasting, were investigated. E. coli O139 K88 ac or ad LT STb were tested for their resistance to antibiotics, available in this region. Oregano‐fed herds demonstrated high significantly (P < 0.001) lower MICs (μg/ml) for ampicillin, doxycyclin, enrofloxacin, gentamycin, oxytetracyclin and sulfamethacin compared to herds with prophylactic use of antibiotics. Resistance to ceftiofur revealed significant (P < 0.05) differences between the antibiotic‐ or oregano‐treated units. The present results confirm literature data, that prophylactic use of antibiotics likely plays a role in inducing resistance of E. coli and other intestinal bacteria. Thus, imposing greater restrictions on antibiotic use in animal agriculture is likely to reduce but not eliminate the occurrence of resistant isolates.  相似文献   

13.
《Veterinary microbiology》1998,61(3):191-197
The attachment to fully characterized primary rumen epithelial cell cultures of Escherichia coli strains isolated from different animal species and expressing F1–F4 or F17 fimbriae was examined. As the cell cultures contained stratified (keratinized) and non-stratified (non-keratinized) cells which grew either confluently or non-confluently, the strength of attachment of the different bacterial strains was assessed in relation to the differentiation state of the cells. Thus, strains having F1 fimbriae attached to all types of cultured cells, while strains with F2 and F3 fimbriae did not bind at all. E. coli strains having F4 or F17 fimbrae attached only to non-keratinized cells, particularly to confluent areas. As membrane glycosylation is known to change with differentiation (keratinization), our results suggest that the attachment of fimbriated E. coli strains which were capable of binding to rumen cells was more likely to be dependent on differentiation than the host specificity of the bacteria.  相似文献   

14.
Diarrhoea due to enterotoxigenic Escherichia coli with fimbriae F4 (ETEC-F4) is an important problem in neonatal and just weaned piglets and hence for the pig farming industry. There is substantial evidence for a genetic basis for susceptibility to ETEC-F4 since not all piglets suffer from diarrhoea after an ETEC-F4 infection. It is assumed that the wild boar was originally ETEC-F4 resistant and that susceptibility towards ETEC arose after domestication. There are different phenotypes in the pig determined by which of the three existing F4 variants (F4ab, F4ac or F4ad) they are susceptible or resistant for. This suggests that several F4 receptors exist, expressed individually or in combination with each other on the brush border of the piglet’s small intestine. As such, the mucin-type glycoproteins (IMTGP) are described as F4ab/ac receptors, while the intestinal neutral glycospingolipid (IGLad) is proposed as an F4ad receptor. GP74 is a putative F4ab receptor. However, the specific genes that encode for the susceptibility are not yet known. In the past decades, linkage analyses revealed that the loci encoding for the receptor(s) for the two most frequent variants F4ab and F4ac were mapped to the 13th chromosome of the pig (Sus scrofa 13, SSC13). After fine mapping, the region of interest was mapped between two microsatellite markers, Sw207 and S0075, and interesting candidate genes surfaced. Numerous SNP analyses and a few expression studies on the three MUC-genes (MUC4, MUC13 and MUC20) and the transferrin receptor gene (TFRC) as well as on some other positional candidate genes have been performed in order to find the causative mutation for the ETEC-F4ab/ac receptor(s). However, until today, the exact mutation causing susceptibility to ETEC-F4 remains unknown.  相似文献   

15.
Escherichia coli (E. coli) strains were collected from young diarrheic calves in farms and field. Strains that expressed the K99 (F5) antigen were identified by agglutination tests using reference antibodies to K99 antigen and electron microscopy. The K99 antigen from a selected field strain (SAR-14) was heat-extracted and fractionated on a Sepharose CL-4B column. Further purification was carried out by sodium deoxycholate treatment and/or ion-exchange chromatography. Monoclonal antibodies to purified K99 antigen were produced by the hybridoma technique, and a specific clone, NEK99-5.6.12, was selected for propagation in tissue culture. The antibodies, thus obtained, were affinity-purified, characterized and coated onto Giemsa-stained Cowan-I strain of Staphylococcus aureus (S. aureus). The antibody-coated S. aureus were used in a co-agglutination test to detect K99+ E. coli isolated from feces of diarrheic calves. The specificity of the test was validated against reference monoclonal antibodies used in co-agglutination tests, as well as in ELISA. Specificity of the monoclonal antibodies was also tested against various Gram negative bacteria. The developed antibodies specifically detected purified K99 antigen in immunoblots, as well as K99+ E. coli in ELISA and co-agglutination tests. The co-agglutination test was specific and convenient for large-scale screening of K99+ E. coli isolates.  相似文献   

16.
Enterotoxigenic Escherichia coli (ETEC) expressing K88 (F4) adhesins are associated with post‐weaning diarrhoea in piglets. Different grain fractions from pea (Pisum sativum) and faba bean (Vicia faba) were tested in vitro for their capacity to counteract aetiological factors, which contribute to the development of diarrhoea. In detail, adhesion of E. coli O149:K91:K88ac (ETEC K88ac) to grain legume products, intended to impair the colonization of the host, was studied as well as interference with receptor binding of the pathogen’s heat‐labile enterotoxin LT, intended to reduce toxin‐inflicted gut cell damage. When comparing different pea and faba bean products tested for their binding capacity of ETEC K88ac, especially pea hulls, but also whole pea meal, starch‐enriched and protein‐enriched pea meal, and digestion‐resistant pea hull and meal fractions showed a higher binding of ETEC K88ac than faba bean products. In contrast to the ETEC K88ac adhesion results, bean hulls proved more effective than pea hulls in preventing GM1 receptor binding of LT. Previous small intestinal segment perfusion experiments we performed with ETEC K88ac‐challenged piglets indicated that both pea and bean hulls have the potential for successful application in diarrhoea prophylaxis and treatment, which is in agreement with and refined by our detection of their different modes of functioning.  相似文献   

17.
Enterotoxigenic Escherichia coli (ETEC) infections result in large economic losses in the swine industry worldwide. The organism causes diarrhea by adhering to and colonizing enterocytes in the small intestines. While much progress has been made in understanding the pathogenesis of ETEC, no homologous intestinal epithelial cultures suitable for studying porcine ETEC pathogenesis have been described prior to this report. In the current study, we investigated the adherence of various porcine ETEC strains to two porcine (IPEC-1 and IPEC-J2) and one human (INT-407) small intestinal epithelial cell lines. Each cell line was assessed for its ability to support the adherence of E. coli expressing fimbrial adhesins K88ab, K88ac, K88ad, K99, F41, 987P, and F18. Wild-type ETEC expressing K88ab, K88ac, and K88ad efficiently bound to both IPEC-1 and IPEC-J2 cells. An ETEC strain expressing both K99 and F41 bound heavily to both porcine cell lines but an E. coli strain expressing only K99 bound very poorly to these cells. E. coli expressing F18 adhesin strongly bound to IPEC-1 cells but did not adhere to IPEC-J2 cells. The E. coli strains G58-1 and 711 which express no fimbrial adhesins and those that express 987P fimbriae failed to bind to either porcine cell line. Only strains B41 and K12:K99 bound in abundance to INT-407 cells. The binding of porcine ETEC to IPEC-J2, IPEC-1 and INT-407 with varying affinities, together with lack of binding of 987P ETEC and non-fimbriated E. coli strains, suggests strain-specific E. coli binding to these cell lines. These findings suggest the potential usefulness of porcine intestinal cell lines for studying ETEC pathogenesis.  相似文献   

18.
We investigated the influence of administration of flax-seed oil on interaction of Lactobacillus plantarum – Biocenol? LP96 and Escherichia coli O8:K88ab:H9 in the gut of germ-free piglets. When compared to animals supplemented with L. plantarum, the counts of lactobacilli in the jejunal and ileal mucosa and in the intestinal content were significantly higher in LMK group (p < 0.0001). Inter-groups comparison of the counts of E. coli K88 adhering to the jejunal and ileal mucosa revealed a significantly decrease in LMK animals (p < 0.001; p < 0.05).  相似文献   

19.
The effect of feeding live Escherichia coli bacteria to sows on the lymphocyte populations in colostrum and milk was studied by in ovo translation of the mRNA of these cells (Kortbeek-Jacobs and van der Donk, 1978). Four E. coli strains were tested: one wild type K88 producing strain, two conjugated K12 strains producing K88 antigen and one wild type K12 strain. Only after feeding the wild type K88 bacteria, colostral lymphocytes contained mRNA coding for anti-K88 antibodies, predominantly of the IgA and IgM isotypes. Milk lymphocytes of the sows receiving one of the other strains were capable of producing more anti-K88 antibodies than the sows that were fed the wild type K88 strain. Antibodies were predominantly of the IgM class. The reactivity of the milk lymphocytes is ascribed to the strain with which the piglets were challenged. The results support the phenomenon of sensitized gut lymphocytes that home to the mammary gland.  相似文献   

20.
The influence of the administration of Lactobacillus plantarum, maltodextrin Maldex 150 and Raftifeed IPX fructooligosaccharides on the inhibition of adhesion of E. coli O8:K88 to the mucosa of the jejunum, ileum and colon as well as on the organic acid levels was investigated in 33 conventional piglets. The counts of E. coli K88 adhering to the jejunal mucosa were significantly decreased (p < 0.05) in Lact. plantarum + Maldex 150 and Lact. plantarum + Maldex 150 + Raftifeed IPX groups. The counts of E. coli K88 adhering to the colonic mucosa of Lact. plantarum + Maldex 150 + Raftifeed IPX and Lact. plantarum + Raftifeed IPX groups were significantly lower (p < 0.05) than in Lact. plantarum and Lact. plantarum + Maldex 150 animals. The acetic acid levels in the ileum and colon of the Lact. plantarum + Maldex 150 + Raftifeed IPX group and Lact. plantarum + Raftifeed IPX group were significantly higher (p < 0.05) than in the Lact. plantarum and Lact. plantarum + Maldex 150 group. The combination of Lact. plantarum, maltodextrin Maldex 150 and Raftifeed IPX proved to be the most effective one to inhibit the counts of E. coli O8:K88 adhering to the intestinal mucosa of the jejunum and colon of conventional piglets.  相似文献   

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