Effects of Syngenta Enogen Feed Corn containing an α-amylase trait on finishing cattle performance and carcass characteristics.

Two experiments evaluated the effects of feeding a new corn hybrid, containing an α-amylase enzyme trait, Syngenta Enogen Feed Corn (SYT-EFC), on feedlot performance and carcass characteristics at two locations. Experiment 1 utilized 300 calffed steers (298.5 ± 16.3 kg of BW) at the University of Nebraska-Lincoln Eastern Nebraska Research and Extension Center Mead, NE. Treatments were designed as a 2 × 2 + 1-factorial arrangement with factors consisting of 1) corn type (SYT-EFC or conventional [CON]) and 2) byproduct type (with or without Sweet Bran [SB]), or a BLEND of STY-EFC and CON without SB. In Exp. 2, 240 crossbred, calf-fed steers (287.6 ± 15.4 kg of BW) were utilized at the University of Nebraska-Lincoln Panhandle Research and Extension Center near Scottsbluff, NE. Steers were fed SYT-EFC, CON, BLEND, or CON with a commercial α-amylase enzyme supplement (CON-E). In Exp. 1, there was an interaction for ADG (P = 0.05) and G:F (P = 0.02). Steers fed SYT-EFC with SB had greater ADG and G:F than CON; however, in diets without SB, SYT-EFC and CON were not different resulting in a 10.1% change in G:F when steers were fed SYT-EFC in SB compared with CON and only 1.6% change between SYT-EFC and CON without SB. Energy values, based on performance data, resulted in a 6.5% and 8.3% change in NEm and NEg, respectively, for steers fed SYT-EFC and CON with SB and 1.6% change for both NEm and NEg for steers fed SYT-EFC and CON without SB. For the main effect of corn trait, steers fed SYT-EFC had greater marbling scores, fat depth, and calculated yield grade compared with CON (P ≤ 0.03). In diets without SB, there was no difference between SYT-EFC, CON, or BLEND for DMI, final BW, ADG, G:F, NEm, or NEg (P ≥ 0.35). In Exp. 2, cattle fed SYT-EFC, BLEND, or CON-E had greater final BW, ADG, and G:F than cattle fed CON (P ≤ 0.03). On average, NEm and NEg were 4.9% and 7.0% greater, respectively, for steers fed amylase enzyme treatments compared with CON (P ≤ 0.01). Hot carcass weights were greater in steers fed α-amylase treatments compared with CON (P < 0.01). Feeding Syngenta Enogen Feed Corn, which contains an α-amylase enzyme trait, at both locations improved feed efficiency in finishing cattle diets containing WDGS or SB.

Finishing performance and diet digestibility for feedlot steers fed corn distillers grains plus solubles and distillers solubles with and without oil extraction.

Three experiments evaluated the effects of corn oil removal using centrifugation in ethanol plants, on animal performance and digestion characteristics by finishing cattle fed by-products. In Exp. 1, 225 crossbred steers (300 ± 9.1 kg) were utilized in a randomized block design with a 2 × 2 + 1 factorial arrangement of treatments. Factors consisted of oil concentration [de-oiled (DO) or full fat (FF)] and by-product type [condensed distillers solubles (CDS) or modified distillers grains plus solubles (MDGS)] compared to a corn-based control. Fat concentration was 6.0% for DO CDS, 21.1% for FF CDS, 9.2% for DO MDGS, and 11.8% for FF MDGS. No oil concentration by by-product type interactions (P ≥ 0.17) were observed. There were no differences in DMI, ADG, or G:F between DO and FF CDS (P ≥ 0.29) or DO and FF MDGS (P ≥ 0.58). No differences (P ≥ 0.25) due to oil concentration were observed for carcass characteristics. Experiment 2 was a 5 × 5 Latin Square digestion trial with treatments similar to Exp. 1. Fat concentration was 8.7% or 15.4% for DO or FF CDS and 9.2% or 12.3% for DO or FF MDGS. Intake and total tract digestibility of fat were greater (P ≤ 0.02) for FF CDS compared with DO CDS. Digestible energy (megacalorie per kilogram), adjusted for intake, was greater (P = 0.02) for steers fed FF CDS compared to DO CDS. Average ruminal pH for cattle fed FF MDGS was greater than DO MDGS (P = 0.06). In Exp. 3, 336 yearling, crossbred steers (352 ± 19 kg) were utilized in a randomized block design with a 2 × 3 + 1 factorial arrangement of treatments. Factors included oil concentration (DO or FF) and inclusion [35%, 50%, and 65% wet distillers grains plus solubles (WDGS)] along with a corn-based control. The fat concentrations of DO and FF WDGS were 7.9% and 12.4%, respectively. A linear interaction (P < 0.01) was observed for DMI, which produced different slopes for DO and FF WDGS. No linear or quadratic interactions were observed for BW, ADG, or G:F (P ≥ 0.31). For the main effect of oil concentration, there were no statistical differences (P > 0.19) for final BW, ADG, or G:F. No statistical differences were observed for all carcass traits (P ≥ 0.34). Corn oil removal via centrifugation had minimal impact on finishing performance suggesting that cattle fed DO by-products will have similar performance to cattle fed FF by-products in dry-rolled and high-moisture corn diets.

Effect of corn residue harvest method with ruminally undegradable protein supplementation on performance of growing calves and fiber digestibility.

Two experiments evaluated the effects of corn residue harvest method on animal performance and diet digestibility. Experiment 1 was designed as a 2 × 2 + 1 factorial arrangement of treatments using 60 individually fed crossbred steers (280 kg [SD 32] initial BW; = 12). Factors were the corn residue harvest method (high-stem and conventional) and supplemental RUP at 2 concentrations (0 and 3.3% diet DM). A third harvest method (low-stem) was also evaluated, but only in diets containing supplemental RUP at 3.3% diet DM because of limitations in the amount of available low-stem residue. Therefore, the 3 harvest methods were compared only in diets containing supplemental RUP. In Exp. 2, 9 crossbred wethers were blocked by BW (42.4 kg [SD 7] initial BW) and randomly assigned to diets containing corn residue harvested 1 of 3 ways (low-stem, high-stem, and conventional). In Exp. 1, steers fed the low-stem residue diet had greater ADG compared with the steers fed conventionally harvested corn residue ( = 0.03; 0.78 vs. 0.63 kg), whereas steers fed high-stem residue were intermediate ( > 0.17; 0.69 kg), not differing from either conventional or low-stem residues. Results from in vitro OM digestibility suggest that low-stem residue had the greatest ( < 0.01) amount of digestible OM compared with the other 2 residue harvest methods, which did not differ ( = 0.32; 55.0, 47.8, and 47.1% for low-stem, high-stem, and conventional residues, respectively). There were no differences in RUP content (40% of CP) and RUP digestibility (60%) among the 3 residues ( ≥ 0.35). No interactions were observed between harvest method and the addition of RUP ( ≥ 0.12). The addition of RUP tended to result in improved ADG (0.66 ± 0.07 vs. 0.58 ± 0.07 for supplemental RUP and no RUP, respectively; = 0.08) and G:F (0.116 ± 0.006 vs. 0.095 ± 0.020 for supplemental RUP and no RUP, respectively; = 0.02) compared with similar diets without the additional RUP. In Exp. 2, low-stem residue had greater DM and OM digestibility and DE ( < 0.01) than high-stem and conventional residues, which did not differ ( ≥ 0.63). Low-stem residue also had the greatest NDF digestibility (NDFD; < 0.01), whereas high-stem residue had greater NDFD than conventional residue ( < 0.01). Digestible energy was greatest for low-stem residue ( < 0.05) and did not differ between high-stem and conventional residues ( = 0.50). Reducing the proportion of stem in the bale through changes in the harvest method increased the nutritive quality of corn residue.

Effects of processing treated corn stover and distillers' grains on performance and total tract digestion of finishing cattle.

Two studies evaluated effects of replacing corn with a pellet containing alkaline treated corn stover, dried distillers' grains plus solubles (DDGS), and distillers' solubles on total tract digestion and performance of finishing cattle. Experiment 1 used 4 ruminally fistulated steers in a 4 × 6 Latin rectangle to evaluate total tract digestion. Treatments consisted of a control (CON) containing 50.3% dry-rolled corn (DRC), 40% modified distillers' grains plus solubles (MDGS), and 5% untreated corn stover. The next 2 treatments replaced 25% DRC (DM basis) with either a CaO-treated stover pellet (STOVPEL) or a pellet consisting of 64% CaO-treated corn stover, 18% DDGS, and 18% corn distillers' solubles (COMBPEL). The last treatment replaced 25% DRC with a mixture of feeds: 10% treated stover pellet, 10% DDGS, and 5% distillers' solubles (COMB). Experiment 2 used 336 crossbred steer calves (301 ± 25 kg initial BW) in a 2 × 3 + 1 factorial to evaluate effects of replacing corn with a pellet containing 64% CaO-treated corn stover, 18% DDGS, and 18% corn distillers' solubles on finishing performance. Factors included level of MDGS (20 or 40%) and pellet inclusion (10, 20, or 30%). The CON diet contained a 50:50 blend of DRC and high-moisture corn and 40% MDGS. All diets contained 5% wheat straw and 4% dry meal supplement. In Exp. 1, no differences ( ≥ 0.50) were observed between the CON, STOVPEL, COMB, or COMBPEL treatments for DM (76.5, 75.4, 72.5, and 78.0%, respectively; SEM 2.5) or OM (79.1, 79.7, 75.7, and 80.5%, respectively; SEM 2.4) digestibility. In Exp. 2, a linear increase ( = 0.03) in DMI was observed as pellet inclusion increased from 0% in the CON (10.6 kg/d [SE 0.13]) to 30% (11.0 kg/d [SE 0.13]) in treatments containing 40% MDGS. A quadratic response ( = 0.03) in DMI was observed as pellet inclusion increased in diets containing 20% MDGS due to greater DMI of the 20% pellet treatment. A linear decrease ( = 0.03) in G:F was observed as the level of pellet inclusion increased from 0 (0.182 [SE 0.02]) to 30% (0.175 [SE 0.02]) in diets containing 40% MDGS. In diets containing 20% MDGS, no differences ( ≥ 0.22) in G:F were observed as pellet inclusion increased from 10 to 30%. In conclusion, replacing up to 20% of corn (DM basis) in diets containing 20% MDGS had minimal impact on performance. Conversely, up to 30% of corn could be replaced in diets containing 40% MDGS with little impact on performance.