Effect of xylo-oligosaccharides from corn cobs autohydrolysis on the intestinal microbiota of piglets after weaning ☆ P. Moura a , S. Marques a , L. Alves a , J.P.B. Freire b, ⁎ , L.F. Cunha b , M.P. Esteves a a Departamento de Biotecnologia, INETI, Estrada do Paço do Lumiar, 22, 1649–038 Lisboa, Portugal b Universidade Técnicade Lisboa, Instituto Superior de Agronomia, Departamento de Produção Agrícola e Animal, Tapada da Ajuda, 1349-017 Lisboa, Portugal Abstract The effect of xylo-oligosaccharides (XOS), a probiotic culture of Saccharomyces cerevisiae (SC) and the combined administration of XOS and SC on the piglet intestinal microbiota was investigated. Twenty four weaned piglets were fed during 4 weeks with one of the following diets: (BD) basal diet; (BD + XOS) basal diet supplemented with xylo-oligosaccharides (20 g kg - 1 ); (BD + SC) basal diet supplemented with S. cerevisiae (6×10 9 CFU kg - 1 ); and (BD + XOS + SC) basal diet supplemented with xylo-oligosaccharides and S. cerevisiae. Samples from the ileum, caecum and colon were collected and analysed for total anaerobes growing in XOS or glucose, xylose and arabinose (GXA) containing media. Specific primers were used to evaluate differences in Bifidobacterium and Lactobacillus populations and ERIC PCR to fingerprint the intestinal microbiota. The lowest number of culturable bacteria was obtained from the ileum of animals fed BD + XOS. The highest PCR titres with Lactobacillus group-specific primers in BD and BD + SC were obtained in the caecal contents. In XOS-supplemented diets the PCR titres were increased or maintained, from the caecum to the colon. Bifidobacteria were not detected in any samples using genus- specific primers. In the dendrogram from ERIC PCR, the piglets fed with XOS diets presented the highest similarity between samples and probiotic reference strains. © 2007 Elsevier B.V. All rights reserved. Keywords: Xylo-oligosaccharide; Pig; Intestinal microbiota 1. Introduction The inclusion of non-digestible oligosaccharides (NDO) with potential prebiotic properties in piglet diets emerges as an alternative to the use of growth promoting antibiotics in nontherapeutic doses, especial- ly during the stressful weaning period. Xylo-oligosac- charides (XOS) are NDO that can be fermented by the swine faecal microbiota. In vitro, XOS are fermented at a slower rate when compared to other oligosaccharides (OS) (Smiricky-Tjardes et al., 2003) and, to our knowledge, there are no data available concerning the in vivo digestibility of XOS in pigs. Therefore, as pigs do not have endogenous enzymes in the small intestine to digest XOS, it is expected that these OS can reach the hindgut where they will be used for the growth of favourable bacteria. However, the use of XOS in animal Livestock Science 108 (2007) 244 – 248 www.elsevier.com/locate/livsci ☆ This paper is part of the special issue entitled “Digestive Physiology in Pigs” guest edited by José Adalberto Fernández, Mette Skou Hedemann, Bent Borg Jensen, Henry Jørgensen, Knud Erik Bach Knudsen and Helle Nygaard Lærke. ⁎ Corresponding author. Tel.: +351 213653408; fax: +351 213630734. E-mail address: jpfreire@isa.utl.pt (J.P.B. Freire). 1871-1413/$ - see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.livsci.2007.01.053