Figure 1 shows that animals in study 5 consumed less than predicted, decreasing the adequacy of the LRNS.
In the LRNS, DMI for growing cattle is predicted based on metabolic shrunk BW (SBW) and diet NEm content (Fox et al.
The LRNS does not limit DMI based on peNDF even though it is known that particle size impacts the particle flow out of the rumen (Offer and Dixon, 2000) likely due to an increase of the time for rumination and comminution of particles, affecting the retention time, the pattern of passage (Vieira et al.
There are a number of potential reasons why ADG was on average under-predicted by the LRNS model when level 2 was used.
Under specific circumstances when the kd of the carbohydrate and protein fractions needed by level 2 of the LRNS are not known, the LRNS level 1 solution may be an alternative to predict animal performance.