Evaluation of pea grains using coupled in vitro assays for precaecal digestion and hindgut fermentation in pigs

The nutrient composition of the pea grain fraction that escapes precaecal digestion may vary in response to the pea variant, affecting its fermentation characteristics in the hindgut. Quantifying the formation of fermentation end products in vivo remains challenging. Therefore, this study investigated the digestion and fermentation characteristics of 12 pea variants using two combined in vitro assays. In vitro indigestible solids (IVIS) of pea grains, representing the fraction of pea grains escaping precaecal digestion, were incubated for 48 h using a modified Hohenheim gas test with pig faeces as inoculum. Gas production was recorded at nine time points, and NH4+-N and volatile fatty acids (VFA) were measured at 8 and 24 h. Precaecal disappearance was high for starch and crude protein ( >94%), whereas fibre fractions remained largely undigested (