Oral immunization against enterotoxigenic colibacillosis in weaned piglets by non-pathogenic Escherichia coli strain with K88 (F4) colonizing factors
Alexa, P.(Vyzkumny Ustav Veterinarniho Lekarstvi, Brno (Czech Republic))E-mail:[email protected] | Hamrik, J. | Stouracova, K. | Salajka, E.
Enterotoxigenic strains of Escherichia coli (ETEC) with colonizing factors K88 (F4) were used to prevent diarrhoea in weaned piglets. ETEC strain bacterin was administered intramuscularly one day prior to weaning and a live culture of non-pathogenic E. coli strain containing colonizing factors (O149:K88; STa-, LT-) was administered orally in 3 hours after weaning. The shedding of the K88 positive E. coli strains was monitored for 3 weeks after weaning by the culture of rectal swabs. The efficacy of such immunization was tested by challenge exposure to enterotoxigenic E. coli O149:K88, LT+ strain on the third or the tenth day after weaning. Following the oral administration of non-pathogenic E. coli strain containing colonizing factors K88 to piglets, the shedding of the administered strain continued for 9 days. No or very small protection against diarrhoea following the challenge exposure to enterotoxigenic E. coli was found in immunized piglets.
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