Feeding chicory inulin to entire male pigs during the last period before slaughter reduces skatole in digesta and backfat

Abstract

The effect of chicory inulin in diets for entire male pigs on skatole levels in colon, rectum and in adipose tissue, and on the composition of microbiota in colon and rectum was evaluated. Entire male pigs of the crossbreed [(Landrace × Yorkshire) × Landrace)] (n = 46; final BW = 101 kg) were fed with a control diet or diets containing either 3, 6 or 9% chicory inulin (containing 70% inulin) during the last four weeks before slaughter. Digesta samples for skatole analyses and for microbiological examinations were taken from colon descendens and rectum. Backfat samples were taken for skatole analyses. The skatole levels in adipose tissue were in general low (0.03 μg/g fat). There was a reduction in skatole with increasing dieatary levels of inulin (linear, P = 0.006). Skatole levels in the digesta samples were also reduced (linear, P < 0.002) by increased dietary inclusion of inulin. Pigs fed with increasing levels of inulin showed a reduction of enterobacteria in colon descendens (linear, P = 0.04) and rectum (linear, P = 0.02), and a tendency towards reduced levels of Enterococcus spp in colon descendens (linear, P = 0.09) and rectum (linear, P = 0.08). In conclusion, addition of chicory inulin in the finishing diet is an effective method to reduce skatole levels in digesta and adipose tissue of the entire male pigs, but the inclusion should be at least 6%, corresponding to 4.2% pure inulin.