Fig. 1.

Relationship between apparent total tract digestibility (ATTD) of nitrogen (N) determined using either (A) acid-insoluble ash (AIA) or (B) chromic oxide (Cr₂O₃) as an indigestible marker and determined using total faecal collection. Data are for individual pigs (n = 5 for each diet) fed either CSM in a sugar-starch-based (Δ), CSM in a wheat-based (□), SBM in a sugar-starch-based (▲), SBM in a wheat-based (■) or a wheat (○) diet. The line of unity is represented by the dashed line while the solid line is the linear regression line. The regression equations are (A) y = 3.25 (SE 3.71) + 0.955 (SE 0.0484)x, R² = 0.941 and (B) y = 21.1 (SE 4.56) + 0.747 (SE 0.0616)x, R² = 0.859.