Abstract
Swine dysentery (SD) is a severe mucohaemorrhagic colitis resulting from infection with the anaerobic spirochaete Serpulina hyodysenteriae. Interactions with other components of the large intestinal microflora enhance colonisation by the spirochaete. In a series of experiments we have demonstrated that pigs fed on a low-fibre diet based on cooked white rice and animal protein completely resisted experimental infection. Addition of soluble fibre (guar gum) but not insoluble fibre (oaten chaff) to the rice diet then allowed colonisation by the spirochaetes, and the development of SD. Examination of other cereal grains and processing methods identified steam-flaked maize and sorghum as ingredients that also reduce susceptibility of pigs to SD. Protective diets are associated with reduced fermentation in the large intestine: this finding offers a new approach to the control of SD.