title: Dietary specific antibodies in spray-dried immune plasma prevent enterotoxigenic Escherichia coli F4 (ETEC) post weaning diarrhoea in piglets.
abstract: In order to establish the mechanism of spray dried plasma powder (SDPP) in improving pig health and performance, a diet containing either 8% SDPP, spray dried immune plasma powder (SDIPP), or control protein (soybean and whey) ration was fed to piglets in an experimental model of enterotoxigenic Escherichia coli F4 (ETEC) post-weaning diarrhoea (PWD). SDIPP was obtained from pigs immunized with a vaccine containing ETEC fimbrial subunit F4 and heat-labile toxin (LT), and SDPP from non-immunized controls. Average daily growth (ADG) was determined, and daily samples of rectal faeces were assessed for diarrhoea (as percentage of dry matter), and ETEC excretion (in CFU/g). SDPP and SDIPP significantly (p<0.05) reduced diarrhoea, and SDIPP significantly reduced ETEC excretion. ADG was not significantly (p>0.05) affected. After the experiment, 30% of piglets tested F4 receptor positive (F4R+). A significant correlation between F4R status and morbidity was found. In F4R+ animals, SDIPP significantly improved diarrhoea and ADG, and decreased ETEC excretion, and SDPP significantly improved diarrhoea and ADG. Surprisingly, SDPP reduced diarrhoea in F4R+ animals without significant reduction of ETEC excretion, which is most likely related to the presence of anti-LT antibodies in SDPP. The results show that oral protection against ETEC by SDPP is attributable to spontaneous antibodies, in this case anti-LT antibodies. Furthermore, the results indicate that the combination of anti-LT and anti-F4 antibodies as in SDIPP is most effective in ETEC prevention. Finally, the F4R distribution in the herd should be taken into account to correctly assess efficacy.
authors.affiliation: Animal Sciences Group of Wageningen University and Research, P.O. Box 65, Lelystad, The Netherlands. theo.niewold@biw.kuleuven.be
authors.forename: T A
authors.initials: TA
authors.lastname: Niewold
authors.forename: A J
authors.initials: AJ
authors.lastname: van Dijk
authors.forename: P L
authors.initials: PL
authors.lastname: Geenen
authors.forename: H
authors.initials: H
authors.lastname: Roodink
authors.forename: R
authors.initials: R
authors.lastname: Margry
authors.forename: J
authors.initials: J
authors.lastname: van der Meulen
mesh_terms: D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D000831:Animals, Newborn; D000907:Antibodies, Bacterial / Q000008:administration & dosage* / Q000097:blood / Q000276:immunology; D015169:Colony Count, Microbial / Q000662:veterinary; D003967:Diarrhea / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary*; D004926:Escherichia coli / Q000254:growth & development / Q000276:immunology* / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary*; D005243:Feces / Q000382:microbiology; D005260:Female; D008297:Male; D010949:Plasma / Q000276:immunology; D011897:Random Allocation; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology / Q000517:prevention & control*; D014886:Weaning; D015430:Weight Gain
chemical_list: D000907:Antibodies, Bacterial