Concentration of volatile sulphur-containing compounds along the gastrointestinal tract of pigs fed a high-sulphur or a low-sulphur diet

Volatile sulphur-containing compounds (VSC) are formed in large quantities in the gastrointestinal tract (GI-tract) of pigs and upon excretion from the animal; these compounds are released from the faeces causing emission of foul odour. However, very little is known about the rate and extent of their production or concentration along the GI-tract of the pig, and to what extent these parameters are influenced by the sulphur content of the diet. In order to address these questions, two diets with different sulphur content were formulated. Growing pigs were fed one of each diet during a minimum of three weeks after which they were killed and gas samples were removed from eight segments of the intact GI-tract and analysed for VSC, hydrogen, carbon dioxide and methane. The concentration of individual VSC in gas samples from the intact GI-tract varied between segments. The total concentration of VSC was high in the cecum and throughout the colon. A significantly higher concentration of methanethiol in the stomach, cecum and proximal colon and of dimethyl sulphide in the cecum and along the colon of pigs fed the high-sulphur diet compared to those fed the low-sulphur diet was measured.