350 W.C. Ellis et al.
Fig. 16.7.Relationships between load of neutral detergent fibre undigested in the rumen, UF (A), mean effective escape rate,2 UF- e
(B) and efflux rate (UF) inlactating () and non-lactating () ruminants. (A and B) Relationships to daily UF; (C–E) Relationships to dietary concentrations of UF. Consumption of increasing UFup to approximately 6 g UF kg^1BW (A) or approximately 0.2 UF OM^1(C) resulted in linear increases in load of UF and escape rates of UF from the rumen,2 UF- e
.These responses are proposed to reflect demand for metabolizable nutrients by the ruminant’s tissues. In contrast, consumption of levels of dietary UF >6 g UF kg^1BW resulted in increases in UF load with a relatively constant2 UF- e
of approximately 0.4 day^1(D). The positive and linear response in UF loads >6 g UF kg^1BWversus UF efflux (A) provide no indication that a maximum UF load was approached in these trials.