British Journal of Nutrition

Metabolism and Metabolic Studies

A high dietary concentration of inulin is necessary to reduce the incidence of swine dysentery in pigs experimentally challenged with Brachyspira hyodysenteriae

Christian F. Hansena1a2, Aracely Hernándeza1, Josie Mansfielda1, Álvaro Hidalgoa3, Tom Laa1, Nyree D. Phillipsa1, David J. Hampsona1 and John R. Pluskea1 c1

a1 Animal Research Institute, School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA 6150, Australia

a2 Department of Large Animal Science, Faculty of Life Sciences, University of Copenhagen, Groennegaardsvej 2, 1870 Frederiksberg C, Denmark

a3 Department of Animal Health, Faculty of Veterinary Science, University of León, León 24071, Spain


A total of sixty surgically castrated male pigs (Large White × Landrace) weighing 31·2 (sd 4·3) kg were used in a randomised block experiment to examine the effect of added dietary inulin (0, 20, 40 and 80 g/kg) on the occurrence of swine dysentery (SD) and on fermentation characteristics in the large intestine after experimental challenge with the causative spirochaete Brachyspira hyodysenteriae. The pigs were allowed to adapt to the diets for 2 weeks before each pig was challenged orally four times with a broth culture containing B. hyodysenteriae on consecutive days. Increasing dietary levels of inulin linearly (P = 0·001) reduced the risk of pigs developing SD; however, eight out of fifteen pigs fed the diet with 80 g/kg inulin still developed the disease. The pH values in the caecum (P = 0·072) tended to decrease, and in the upper colon, the pH values did decrease (P = 0·047) linearly with increasing inulin levels in the diets, most probably due to a linear increase in the concentration of total volatile fatty acids in the caecum (P = 0·018), upper colon (P = 0·001) and lower colon (P = 0·013). In addition, there was a linear reduction in the proportion of the branched-chain fatty acids isobutyric acid and isovaleric acid in the caecum (P = 0·015 and 0·026) and upper colon (P = 0·011 and 0·013) with increasing levels of dietary inulin. In conclusion, the present study showed that a diet supplemented with a high level of inulin (80 g/kg) but not lower levels reduced the risk of pigs developing SD, possibly acting through a modification of the microbial fermentation patterns in the large intestine.

(Received October 29 2010)

(Revised March 14 2011)

(Accepted March 14 2011)

(Online publication June 07 2011)


c1 Corresponding author: Professor J. R. Pluske, fax +61 89 360 6628, email


Abbreviations: BCFA, branched-chain fatty acids; N-NH3, NH3 nitrogen; SD, swine dysentery; VFA, volatile fatty acids