title: Seroprevalence of F4+ enterotoxigenic Escherichia coli in regions with different pig farm densities.
abstract: Sera of young sows from 135 closed Belgian pig breeding farms were examined for the presence of serum antibodies specific for the F4 fimbrial antigen of enterotoxigenic Escherichia coli (ETEC). Since 80% of all pig farms in Belgium are located in the provinces West-Vlaanderen (44%, approximately 18 farms/10 km2), Oost-Vlaanderen (20%, approximately 9 farms/10 km2), Antwerpen (10%, approximately 5 farms/10 km2) and Vlaams-Brabant (6%, approximately 3 farms/10 km2), the farms examined were randomly selected in these four regions. On 68% of all tested farms, sows were not vaccinated against enteric colibacillosis. In general, 65% of these non-vaccinated farms were F4-seropositive (mean optical density [OD405] >0.5) of which 38% were weakly (mean OD405 = 0.5-1.0), 21% moderately (mean OD405 = 1.0-2.0) and 6% strongly positive (mean OD405 > or =2.0). These percentages showed major differences between the four provinces. In Vlaams-Brabant, only 31% of non-vaccinated farms were seropositive, of which most were regarded as weakly positive. In Antwerpen, Oost- and West-Vlaanderen however, this percentage was clearly higher and respectively 68, 71, and 79% of non-vaccinated farms were seropositive, of which most were weakly positive. These observations indicate that F4+ ETEC is widely spread and highly prevalent on non-vaccinated pig breeding farms in Belgium. Moreover, an increasing F4-seropositivity with increasing pig farm density suggests a possible influence of the swine density on the prevalence of F4+ ETEC infections.
authors.affiliation: Laboratory of Veterinary Immunology, Faculty of Veterinary Medicine, Universiteit Gent, Merelbeke, Belgium. wim.vanderbroeck@rug.ac.be
authors.forename: W
authors.initials: W
authors.lastname: Van den Broeck
authors.forename: E
authors.initials: E
authors.lastname: Cox
authors.forename: B M
authors.initials: BM
authors.lastname: Goddeeris
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology; D001426:Bacterial Proteins / Q000276:immunology / Q000302:isolation & purification*; D001530:Belgium / Q000453:epidemiology; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D004926:Escherichia coli / Q000276:immunology / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000276:immunology / Q000662:veterinary*; D005260:Female; D036781:Fimbriae Proteins; D010861:Fimbriae, Bacterial / Q000276:immunology; D012044:Regression Analysis; D016036:Seroepidemiologic Studies; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology* / Q000276:immunology / Q000382:microbiology; D014611:Vaccination / Q000662:veterinary
chemical_list: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; C022924:colonization factor antigens; D036781:Fimbriae Proteins