Effects of Kernel Processing of Corn Silage with and without the Brown Midrib Trait on Finishing Performance of Steers

The effect of kernel processing and corn silage hybrid was evaluated for growth performance of beef cattle fed dry rolled corn-based diets. Crossbred steers (n = 360, 400 ± 5.35 kg) were blocked into 2 BW groups and assigned randomly to one of 36 pens (10 steers/pen). The three corn silage hybrids utilized were a standard corn hybrid (CON; hybrid TMF2H708), a brown midrib hybrid (bm3; hybrid F1557952) and Unified™ brown midrib corn silage with SilaSoft™ kernel technology with a floury endosperm (bm3-EXP; hybrid F15578XT). The treatment design was a 2 × 3 factorial with the three hybrids and kernel processed or not. Data were analyzed using the MIXED procedure of SAS (SAS Inst. Inc., Cary, NC), with pen serving as the experimental unit. Silage was included in the finishing diet at 40% on a DM basis. Cattle were slaughtered on d 104 of the trial. Cattle were adapted to their finishing treatment diets over a period of 21 days and 4 diets. There were no interactions observed between kernel processing and corn silage hybrid (P > 0.45). Feeding both bm3 hybrids increased DMI and ADG over the CON silage hybrids (P < 0.01). Steers fed CON had the lowest G:F (0.132; P < 0.03), whereas cattle fed bm3 and bm3-EXP silage hybrids had similar G:F (0.138 and 0.139, respectively; P = 0.88). Cattle fed bm3-EXP had a greater HCW than CON steers (P = 0.04), with bm3 fed steers similar to bm3-EXP (P = 0.75). Kernel processing silage decreased DMI (P = 0.04) with a similar ADG (P = 0.93), but tended to increase G:F (P = 0.10) by 2.6% with 40% inclusion of silage in the diet. The improvement due to the kernel processing at harvest improved the silage by 6.5% (2.6/0.40), as compared to not kernel processing the corn silage hybrids. Kernel processing and using brown midrib silage both improve G:F of finishing cattle when fed at 40% in grain-based diets.