1680
Grain processing methods and concentration of corn silage NDF in the finishing diet of Nellore bulls
Grain processing methods disrupt the protein matrix of starch granules and increase surface area allowing more starch to be digested and higher animal performance of cattle fed high concentrate diets. There are some interaction of grain processing and NDF concentration. Inadequate fiber concentration could result in metabolic disturbs decreasing animal performance. This study evaluated two grain processing methods (coarsely ground and steam flaked corn) and these methods interaction with four corn silage NDF concentrations (4, 7, 10 and 13%) on animal performance. Two hundred and thirty seven Nellore bulls (336 kg BW ± 1.53) were fed diets containing corn silage; corn; soybean meal; urea and a mineral and vitamin premix. The animals were blocked by initial BW and randomly allocated to 24 pens in groups of 6 animals and to 8 pens in groups of 12 animals. The parameters evaluated were DMI, ADG and FE. The experiment lasted 117 days and the data was analyzed using mixed procedure of the SAS package. Block was considered the random effect. Grain processing method, NDF concentration and grain processing method X NDF concentration were considered fixed effects. Linear and quadratic effects of NDF concentration were tested for each grain processing method. Animals fed flaked corn had higher FE than animals fed ground corn. From all concentrations of corn silage NDF, 7 and 4%, had higher FE for treatments containing ground corn and flaked corn, respectively. It was concluded that corn flaking is an efficient way to improve performance of Nellore cattle in feedlot in comparison to ground corn and that 4 to 7% of NDF from corn silage are efficient concentrations to obtain good results on animal performance.
Table 1. Performance of cattle receiving diets with two grain processing methods and different concentrations of corn silage NDF
Grain processing method |
Ground corn |
Flaked corn |
||||||||||
Corn silage NDF concentrations |
Contrast |
Corn silage NDF concentrations |
Contrast |
|||||||||
4 |
7 |
10 |
13 |
L |
Q |
4 |
7 |
10 |
13 |
L |
Q |
|
IBW, kg |
344.0 |
344.1 |
343.9 |
343.9 |
NS |
NS |
343.8 |
343.9 |
344.1 |
343.9 |
NS |
NS |
FBW, kg |
512.1 |
518.2 |
527.2 |
517.6 |
0.05 |
0.001 |
520.3 |
517.5 |
521.1 |
535.7 |
0.01 |
0.001 |
DMI, kg |
8.55 |
8.85 |
9.45 |
9.5 |
0.01 |
0.12 |
8.48 |
8.75 |
8.8 |
9.68 |
0.01 |
0.001 |
ADG, kg |
1.44 |
1.49 |
1.57 |
1.48 |
0.05 |
0.002 |
1.51 |
1.48 |
1.51 |
1.64 |
0.01 |
0.001 |
ADG/DMI |
0.168 |
0.169 |
0.166 |
0.157 |
0.01 |
0.15 |
0.181 |
0.172 |
0.172 |
0.169 |
0.04 |
0.38 |
Keywords: grain processing; NDF concentration; Nellore