Including readily digestible non-fiber carbohydrate in fermentation cultures in which
low-quality grass hay was the principal substrate depressed extent of fiber digestion unless
pH was prohibited from dropping. In contrast, rate of fiber digestion was depressed in
response to added NFC regardless of pH manipulation. The NFC sources evaluated in these
studies did not exhibit consistent, systematic differences in their effect on in vitro rate or
extent of digestion. In general, these data were interpreted as verifying that both pH and
NFC-specific effects may play a role in potential depressions in fiber digestion observed
when highly digestible NFC sources are fed to ruminants consuming low-quality forage as
their basal feedstuff