The objective of the present study was to evaluate the performance of beef cattle in feedlots fed diets
containing either whole-crop maize silage or sugarcane silage, and with different formulations. Five diets were evaluated:
MSF - diet containing whole-crop maize silage, with fixed formulation during feedlot period; MSV- diet containing wholecrop
maize silage, with variable formulation according to feedlot phase; SCSF - diet containing sugarcane silage with fixed
formulation; SCSV- diet containing sugarcane silage, with variable formulation; SCSV/MSV- SCSV diet in initial half of fedlot
and MSV diet in final half of feedlot period, respectively. It was used a complete random experimental design, with five
treatments and three replicates (pens). It was used 285 steers at 36 months of age, with an initial body weight of 362.4 kg. Diets
with whole-crop maize silage promoted greater intake of dry matter (10.5 kg and 2.4% BW) compared with diets containing
sugarcane silage (10.1 kg and 2.3% BW). There was no effect of the silages on average daily gain (1.348 kg/animal/day)
and live weight at slaughter (481.2 kg BW). SCSV/MSV diet promoted the worst feed conversion (8.0 kg DM/kg BW). Animals
fed diets composed of whole-crop maize silage presented greater weight of hot carcass, of carcass yield and subcutaneous
fat thickness (262.1 kg, 54.1% and 6.2 mm) compared with the animals fed sugarcane silage (252.5 kg, 52.7% and 4.8 mm).
The use of sugarcane silage in diets for finishing beef cattle is feasible and the adjustment of formulation during confinement
period does not influence performance of the animals. Replacement of sugarcane silage by whole-crop maize silage during
the feeding period affects negatively feed conversion.
Key Words: average daily gain, dressing percentage, hot carcass weight, intake