Composition of the gastrointestinal contents (including counts of E. coli in growing pigs fed high tannins diet base on shred acorns from Downy Oak (Quercus pubescens)

Objectives: Reference differently report antibacterial properties of dietary tannins on several bacterial strains of intestinal microflora in different animal species. Preliminary results from an experimental combined diet based on ripe acorns (high tannins content starchy kernels, used for feeding pigs in the Mediterranean basin) shred, are reported with regards to E. coli count in the gut. Methods: A total of 10 growing pigs, after an adaptation diet (8 days), were housed individually and divided into 2 groups: n=6 represented the tannins fed groups (T) receiving a high tannins combined diet based on ripe hulled shred acorns (70% acorns shred and 30% complete diet, DM: 695 g/kg; starch: 447 g/kg DM; Tannic Acid Equivalent: 36.1 g/kg DM); n=4 represented the control group (C) receiving a soybean and cereal based complete diet (DM: 890 g/kg; starch: 435 g/kg DM; TAE: n. d.). After 8 d of experimental feeding, at dissection, ingesta samples of stomach, ileum and caecum were analysed as DM, starch and pH. Furthermore, counts of E. coli on pooled digesta of small intestine and on samples of caecum were carried out. Results: Chemical composition and pH of chyme of alimentary tracts from carcasses of the 2 experimental groups of pigs are reported below. Conclusions: The combined diet with 70% of shred acorns didn’t affect the intestinal content of E. coli after 1 week of exposure to tannins from Downy Oak acorns.