The objective was to evaluate the effect of substitution of corn grain by pearl millet,
ground or whole, on intake, digestibility, performance, blood parameters, economic
evaluation and feeding behavior young bulls of dairy origin finished in feedlot. We
used 28 young bulls of dairy origin with average initial weight of 262.70 ± 26.04 kg,
distributed in a completely randomized design with a 2 x 2 factorial arrangement, with
seven replicates per treatment. We evaluated four experimental diets containing two
types of grains (corn x pearl millet) and two forms of processing of the grains (ground
x whole). The dry matter (DMI), crude protein (CPI) (P=0.059), ether extract (EEI)
and non-fiber carbohydrates (NFCI) had interaction (P<0.05) among the factors
evaluated. The whole millet diet increased the DMI (% PV), EEI and NFCI compared
to ground pearl millet. The grain whole millet increased DMI, CPI, EEI and NFCI
compared to whole corn grain. Replacing corn grain by grain millet reduces the
apparent digestibility coefficients of ether extract (EEADC), non-fibrous
carbohydrates (NFCAD) and total digestible nutrients (TDN) (P<0.05). The
processing of grain increases the apparent digestibility coefficients dry matter and
nutrients (P<0.05), except for NDF (P>0.05). There was interaction between the
factors (P<0.05) for the concentration of alkaline phosphatase, which was lower for
the whole millet diet compared to other evaluated diets. The final weight, total weight
gain and average daily gain were similar regardless of the types (P>0.05) and the
processing of grains (P>0.05). The evaluated factors do not alter the gross revenue
(P>0.05), but modified net revenue (P<0.05), which was lower for the whole pearl
millet diet compared to other evaluated diets. The food and rumination times have
not changed in response to the type (P>0.05) or the processing of grains (P>0.05).
On the other hand, the idle time is greater for animals fed corn (P<0.05) and time of
other activities it greater for pearl millet diet (P<0.05). There was an interaction
(P<0.05) among the factors evaluated on the number and duration of rumination
chews per bolus, which were higher for the whole pearl millet diet. Thus, the grain of
pearl millet can replace corn grain in the diet of dairy male in confinement for
promoting similar performance. However, pearl millet grains should be provided
ground, due to increased availability energy promoted by processing resulting in
increased feed efficiency and economic return of activity.
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