Effects of glycerin concentration in steam-flaked corn-based diets with supplemental yellow grease on performance and carcass characteristics of finishing beef steers.

Forty-eight individually fed crossbred steers (initial BW = 381 ± 7.61 kg) were used to determine the effects of glycerin (GLY) concentration in steam-flaked corn (SFC)-based diets with added yellow grease on animal performance and carcass characteristics. Glycerin was included at 0, 2.5, 5, and 10% dietary DM replacing SFC. A completely randomized design was used with steers as the experimental unit, and the model included the fixed effects of diet. Contrast statements were used to determine linear and quadratic effects of GLY inclusion. Final BW and DMI were not affected (P > 0.27) by GLY concentration. Average daily gain and G:F based on live BW did not differ as GLY level increased in the diet from 0 to 10% of DM (P > 0.33). Carcass-adjusted final BW and carcass-adjusted G:F were also not affected by GLY concentration (P > 0.22); however, carcass-adjusted ADG tended to respond quadratically by decreasing from 2.5 to 5% GLY inclusion and increasing thereafter (P = 0.10). Calculated dietary NEm and NEg did not differ as GLY increased in the diet (P > 0.37). Hot carcass weight tended to respond quadratically, decreasing from 2.5 to 5% GLY and increasing thereafter (P = 0.10). Likewise, dressing percentage tended to respond quadratically by decreasing from 2.5 to 5% GLY inclusion and increasing to 10% GLY inclusion (P = 0.09). Fat thickness decreased linearly as GLY inclusion increased in the diet (P < 0.01); however, no differences were detected in marbling score and LM area (P > 0.21). Calculated yield grade (YG) decreased linearly as GLY increased in the diet from 0 to 10% of DM (P = 0.04). Based on our results, there was no animal performance benefit for replacing SFC with GLY in diets containing yellow grease, and the only change in carcass merit was a slight improvement in YG.

Effects of 35% corn wet distillers grains plus solubles in steam-flaked and dry-rolled corn-based finishing diets on animal performance, carcass characteristics, beef fatty acid composition, and sensory attributes.

Fifty-four individually-fed Hereford-Angus cross steers (initial BW = 308 ± 9 kg) were used in an unbalanced randomized block design with a 2 × 2 factorial treatment arrangement to determine effects of corn processing method and corn wet distillers grains plus solubles (WDGS) inclusion in finishing diets on animal performance, carcass and beef characteristics, and sensory attributes. Dietary treatments included steam-flaked corn- (SFC) and dry-rolled corn (DRC)-based finishing diets containing 0 or 35% WDGS (DM basis; 0SFC and 35SFC, 0DRC and 35DRC, respectively). Yellow grease was used to equilibrate fat content of diets. Steers were fed 174 d, and were harvested on a single date when the mean ultrasound fat thickness was estimated to be 1.30 cm. No interactions between corn processing and WDGS were observed for performance or carcass characteristics (P ≥ 0.11). Final BW (556 ± 14 kg) and ADG (1.43 ± 0.06 kg) were not affected (P ≥ 0.25) by dietary treatment. Steers fed SFC-based diets consumed less feed, and were 10.6% more efficient (P < 0.01) than those fed DRC-based diets. Including WDGS in finishing diets improved feed efficiency of steers consuming both SFC- and DRC-based diets (P ≤ 0.04). Dietary treatment did not affect HCW, dressing percentage, fat thickness, or yield grade (P ≥ 0.27). Including WDGS in finishing diets decreased the concentration of 16:1cis-9, 18:1cis-9, and 18:1cis-11 fatty acids, and tended (P ≤ 0.10) to increase total fat concentration of steaks compared with diets without WDGS. A corn processing method by WDGS interaction was detected for 18:1trans-11 where steaks from 0DRC diets had decreased concentrations compared with other diets. There were no dietary effects on palatability attributes (P > 0.20). Livery-organy aromatics (P = 0.03) and sweet basic tastes (P = 0.01) in steaks from the 35SFC treatment were more intense than in other treatments, but were barely detectable. Thiobarbituric acid reactive substances tended to be greater in steaks from steers fed WDGS after 5 d of storage (P = 0.10), and were greater after 7 d. (P < 0.01). Inclusion of WDGS used in this experiment improved G:F with minimal impacts on carcass characteristics. Both WDGS inclusion and corn processing method impacted fatty acid composition. However, diet had minimal impacts on palatability attributes. When compared with diets fat-equilibrated with yellow grease, the primary concern with incorporating WDGS appears to be decreased shelf-life after 5 d of storage.

Effects of twenty percent corn wet distillers grains plus solubles in steam-flaked and dry-rolled corn-based finishing diets on heifer performance, carcass characteristics, and manure characteristics.

Two hundred sixty-four crossbred heifers (initial BW = 354 kg ± 0.5) were used to determine effects of corn processing method and wet distillers grains plus solubles (WDGS) inclusion in finishing diets on animal performance, carcass characteristics, and manure characteristics. The study was conducted as a randomized complete block with a 2 × 2 factorial arrangement of treatments. Dietary treatments included steam-flaked corn (SFC)- and dry-rolled corn (DRC)-based finishing diets containing 0 or 20% WDGS (0SFC, 20SFC, 0DRC, and 20DRC, respectively). Heifers averaged 154 d on feed and were marketed in 3 groups. There were no interactions between corn processing method and WDGS detected (P ≥ 0.29) for any performance or carcass response variables. Heifers fed diets containing WDGS tended to have greater final BW (P = 0.10) and increased G:F (P = 0.08) compared with heifers fed diets without WDGS. Heifers fed SFC-based diets consumed 7% less feed (P < 0.01) and were 9% more efficient (P < 0.01) than heifers fed DRC-based diets. Carcass characteristics were not affected by corn processing method or WDGS inclusion (P ≥ 0.16). Intakes of OM, N, P, and K were greater (P ≤ 0.05) for heifers fed DRC-based diets than those fed SFC-based diets, which resulted in greater net accumulation of the nutrients in the manure (P ≤ 0.04). Heifers fed diets containing WDGS had greater (P < 0.01) intakes of N, P, and K than heifers fed diets without WDGS. As a result, a greater net accumulation of P and K (P ≤ 0.03) and N (P = 0.10) were present in the manure from cattle fed diets containing WDGS compared with those fed diets without WDGS. There was no interaction (P ≥ 0.16) between corn processing and WDGS on N volatilization losses. Nitrogen volatilization losses from manure (expressed as a percentage of intake and g·heifer(-1)·d(-1)) were greater (P < 0.01) for heifers fed SFC-based diets than heifers fed DRC-based diets. Feeding DRC-based finishing diets to heifers resulted in increased manure production and nutrient excretion and decreased N volatilization. Both corn processing method and WDGS inclusion affected animal performance and manure characteristics.

Use of dried distillers grains throughout a beef production system: effects on stocker and finishing performance, carcass characteristics, and fatty acid composition of beef.

A 2-yr study was conducted using a 3 × 2 factorial arrangement of treatments to evaluate the effects of feeding dried distillers grains throughout a beef production system on performance, carcass characteristics, and fatty acid profile of beef. Factors were wheat pasture supplement [no supplement (CON), dry-rolled corn (DRC), and dried distillers grains (DDG)] fed at 0.5% BW daily and finishing diet [steam-flaked corn based diet containing 0 (SFC) or 35% (35DDG) DDG]. Each year, 60 preconditioned Hereford steers (initial BW = 198 kg ± 3) grazed winter wheat pasture with or without supplement. Body weight gain was 8% greater for steers consuming DDG supplement compared with CON and DRC steers (P < 0.01). After the grazing period, pastures within supplement treatment were randomly assigned to SFC or 35DDG. There was no supplement by finishing diet interaction for any performance or carcass variable of interest (P ≥ 0.41). Previous supplementation on winter wheat affected BW at feedlot entry and adjusted G:F (P ≤ 0.05) but had no effect on finishing ADG or carcass traits (P ≥ 0.12). On a carcass-adjusted basis, steers consuming 35DDG had reduced final BW, ADG, G:F, and total BW gain throughout the system (P ≤ 0.04) compared with SFC. Additionally, steers consuming 35DDG had reduced HCW, dressing percent, and fat thickness (P ≤ 0.03) compared with SFC. There was a supplement by finishing diet interaction (P = 0.02) for 18:0, in which cattle supplemented with DRC and fed the SFC finishing diet had the lowest concentration of 18:0 but DRC supplemented steers fed the 35DDG diet had the greatest concentration. The interaction was not significant (P ≥ 0.18) for other fatty acids. Main effects of supplement and finishing diet affected (P ≤ 0.05) several other fatty acids of interest, particularly 18:2, which is associated with reduced flavor-stability of beef. The use of DDG as a supplement to wheat pasture resulted in greater ADG during wheat grazing and heavier BW at feedlot entry, but final BW was not different from CON or DRC groups. Feeding DDG at 35% DM in steam-flaked corn-based finishing diets reduced ADG, G:F, and HCW, and affected the fatty acid composition of beef.

Wet distillers grains plus solubles concentration in steam-flaked-corn-based diets: Effects on feedlot cattle performance, carcass characteristics, nutrient digestibility, and ruminal fermentation characteristics.

Two experiments were conducted to determine the effects of wet distillers grain plus solubles (WDG; <15% sorghum grain) concentration in steam-flaked corn (SFC) diets on feedlot performance, carcass characteristics, ruminal fermentation, and diet digestibility. In Exp. 1, six hundred crossbred steers (364 ± 35 kg of BW) were used in a randomized complete block design with 8 replications/treatment. Dietary treatments consisted of a dry-rolled corn (DRC) control diet without WDG, a SFC control without WDG, and SFC with 4 WDG concentrations (15, 30, 45, 60% DM basis) replacing SFC, cottonseed meal, urea, and yellow grease. Final BW, ADG, G:F, HCW, and 12th-rib fat depth were greater (P ≤ 0.05) for SFC compared with DRC. Dry matter intake tended (P = 0.06) to be greater for DRC compared with SFC. Final BW, ADG, G:F, HCW, 12th-rib fat depth, and marbling score decreased linearly (P < 0.01) with increasing WDG concentration. In Exp. 2, six ruminally and duodenally cannulated crossbred steers (481 ± 18 kg of BW) were used in a 6 × 6 Latin square design using the same diets as Exp. 1. Ruminal, postruminal, and total tract OM and NDF digestibility were not different (P > 0.14) for DRC compared with SFC. Ruminal and total tract starch digestibility were greater (P < 0.01) for SFC compared with DRC. Dry matter and OM intake were not different (P ≥ 0.43) among WDG treatments. Ruminal and total tract OM digestibility decreased linearly (P < 0.01) with increasing WDG concentration. Intake, ruminal digestibility, and total tract digestibility of NDF increased linearly (P < 0.01) with increasing WDG concentration. Starch intake decreased linearly (P < 0.01) with increasing WDG concentration. Ruminal starch digestibility increased (P = 0.01) with increasing concentration of WDG. Total tract starch digestibility decreased quadratically (P < 0.01) with increasing concentration of WDG. Feeding SFC improved steer performance compared with DRC. The concentration of WDG and corn processing method influences nutrient digestibility and ruminal fermentation. The addition of WDG in SFC-based diets appears to negatively affect animal performance by diluting the energy density of the diet.