Investigation Of O-serogroups, Enterotoxins And Fimbriae Of Escherichia Coli From Piglets With Neonatal, Postweaning Diarrhea And/or Edema Disease In Part Of Jiangsu Province

Pathogenic Escherichia coli is a major cause of piglet diarrhea which has been one of the most common diseases economically. To outline the E. coli isolates from diarrheal piglets in Jiangsu province and its surrounding area during2011-2013,576E. coli isolates from piglets with yellow and white sour, postweaning diarrhea and/or edema disease were characterized.1O-serotypes, entertoxins and fimbriae of Escherichia coli from piglets with neonatal diarrhea348E. coli strains from piglets with neonatal diarrhea were characterized. For O-serogroups,251strains were determined, while93strains were unserotypeable, and4strains were self-agglutinated. Forty-four serotypes were identified among251E. coli isolates.O6、O9、O20、 O24、O101、O105and0149were the prevalent serotypes in the serotypeable isolates, they harboured174strains (69.32%,174/251). There were some differences between this study and previous reports of common serotypes of E. coli causing piglet neonatal diarrhea.024and O1O5were predominant serotypes found in this study which had seldomly reported in the past. O-serogroups of E. coli causing piglet neonatal diarrhea in Jiangsu province showed a diverse distribution.Multiplex-PCR was used to determine the following toxin genes of348E. coli isolates, sta, stb, It, stx2e and eaeA.202isolates with toxin genes were detected (58.05%,202/348). Single or multiple toxin gene profiles reached to thirteen, in which lt+、stb+、sta+、sta+、lt、were predominant genotypes, which harboured69,55,23and20isolates, respectively. According to the profile of toxin genes, the202strains of E. coli can be divided into five categories, including ETEC, STEC, AEEC, ETEC/STEC, ETEC/AEEC.171strains were classified into ETEC, accounting for84.65%(171/202) of the toxin gene(s) positive strains of E. coli. These results suggested that ETEC was more frequently associated with neonatal diarrhea of pigs in Jiangsu aera. Fimbria of F4, F5, F6and F41in the348E. coli isolates were determined by monoclonal antibody agglutination test. The results showed that50strains (14.37%,50/348) of E. coli carried one or more fimbrial adhesins. Six fimbria profiles were observed among50fimbriated E. coli, including23strains belonged to F4+F5+,11to F41+,9to F4+,3to F4+,3to F5+F41+and1to F5+Refer to the relationship between O-serogrouops of E. coli, enterotoxin gene profiles and fimbrial antigens, among202toxin gene positive E. coli isolates, O20,024, O26,078,0101and0149were predominant serogroups, which harboured23,33,5,6,5and38isolates respectively. The common0149isolates often harboured stb and stb plus eaeA genes, each harboured25and9isolates.024strains bore stb, stb plus It and lt genes frequently, which had13,10and8isolates, respectively.49isolates with toxin genes and fimbriae showed ten combination types, in which O149had38isolates.11isolates bearing stb+/F41+,9with stb+eaeA+/F4+F5+,7with stb+/F4+,7with stb+/F4+F5+,3with lt+7F4+F5+F41+and1with lt+eaeA+/F4+F5+belonged to O149, while5isolates bearing stb+/F4+F5+belonged to O24.2O-serogroups, enterotoxins and fimbriae of Escherichia coli from Piglets with postweaning diarrhea and or edema disease228E. coli strains from piglets with postweaning diarrhea and/or edema disease were characterized. For O-serogroups,163strains were determined, while61strains were unserotypeable, and4strains were self-agglutinated.28serotypes were identified among163E. coli isolates. O9,014.024.044.065and O101were the prevalent serotypes in the serotypeable isolates, they harboured128strains (78.52%,128/163). There were some differences between this study and previous reports of common serotypes of E. coli from piglets with postweaning diarrhea and/or edema disease.024and044were predominant serotypes found in this study which had seldomly reported in the past. O-serogroups of E. coli causing piglet postweaning diarrhea and/or edema in Jiangsu province showed a diverse distribution.Multiplex-PCR was used to determine the following toxin genes of228E. coli isolates, sta, stb, lt, stx2e and eaeA.110isolates with toxin genes were detected (48.25%,202/348). Single or multiple of toxin gene profiles reached to thirteen, in which eaeA、sta、stx2e plus eaeA were predominant genotypes, which harboured39,20and13isolates, respectively. According to the profile of toxin genes, the110strains of E. coli can be divided into seven categories:ETEC、 STEC、AEEC、ETEC/STEC、STEC/AEEC、ETEC/AEEC、ETEC/STEC/AEEC,which harboured34(30.91%),6(5.45%),39(35.45%),1(0.91%),13(11.82%),15(13.64%) and2(1.82%) isolates. Fimbria of F4, F5, F6, F18and F41in the228strains of E. coli isolates were determined by monoclonal antibody agglutination test. The results showed that54(23.68%,54/228) strains of E. coli carried one or more fimbrial adhesins.9fimbria profiles were observed among54fimbriated E. coli, in which21(38.89%,21/54) strains belonged to F18+,17(31.48%,17/54) strains belonged to F5+F41+, and7(12.93%,7/54) belonged to F5+.Refer to the relationship between O-serogrouops of E. coli, enterotoxin genes profiles and fimbrial antigen, among110toxin gene positive E. coli isolates,014,024,044,065and0101were predominant serogroups, which harboured8,29,7,7and5isolates respectively. The common024isolates often harboured stx2e plus eaeA and eaeA genes.54fimbria positive strains belonged to12serogroupes, in which O24(25isolates) was the predominant serogroup,11of the25isolates expressed F5F41, and9expressed F18.32isolates with toxin genes and fimbriae showed19combination types, in which stx2e+eaeAF18+(5isolates) and sta+lt+/F18+(4isolates) were predominant types.024as a predominant serotype which had seldomly reported in the past, had8combinations in this study, in which stx2e+eaeA+/F18+and sta+lt+/F18+were the predominant combination types, each had3isolates repectively.