Microbial activities of faeces from unweaned and adult pigs, in relation to selected fermentable carbohydrates

A comparison of in vitro microbial activity was made between inocula from f aeces of adult and unweaned pigs, using a range of carbohydrate-rich substr ates. The substrates tested were classified into groups (fibre-rich, grains , gums, pectin, saccharides, storage carbohydrates, and miscellaneous). Pro ximate and fibre analyses were determined for all substrates tested. Fermen tation kinetics were measured according to the cumulative gas production te chnique. End-point products such as gas, volatile fatty acids and ammonia w ere also determined. The faeces from the adult pigs (ATF) were collected fr om four castrated finisher pigs (Dutch Landrace X Great Yorkshire). These w ere offered a diet based on highly digestible maize starch and fish meal, s o as to be as free as possible of fermentable carbohydrates. The unweaned p iglet faeces were collected from 19 unweaned piglets (male and female) whic h were 27 to 30 days old. The parameters were tested for significance by an analysis of variance using the Tukey's studentized range test of multiple comparisons. There were significant differences in the fermentation pattern s both due to source of substrate and inoculum. It would appear that the me tabolic activity of the microflora does differ significantly between adult and weanling pigs, though this varied for the different carbohydrates teste d. Suggestions are made as to how to select potential carbohydrate ingredie nts for an in vivo experiment, based on their in vitro fermentation charact eristics.