Effects of roughage source and distillers grain concentration on beef cattle finishing performance, carcass characteristics, and in vitro fermentation1,2

Abstract

Two experiments were conducted to evaluate the effects of wet distillers grains plus solubles (DG) and roughage source on finishing cattle performance, carcass characteristics, and in vitro fermentation. In Exp. 1, crossbred beef steers (n=224, initial BW=349 kg) were used in a randomized complete block design with a 2 × 3 + 1 factorial arrangement of treatments. Experimental diets were a standard steam-flaked corn (SFC)-based control (no DG and 10% alfalfa hay), and either 15 or 30% DG (DM basis) with roughage sources of alfalfa hay (15-AH and 30-AH), Coastal bermudagrass hay (15-BG and 30-BG), or sorghum silage (15-SS and 30-SS). Within each DG concentration, roughages provided an equivalent percentage of NDF to 7.5% AH. Steers consuming 15% DG had greater (P < 0.04) final BW, ADG, and G:F than those fed 30% DG. Feeding AH as the roughage source with DG resulted in decreased final shrunk BW and ADG (P < 0.02) compared with BG and SS. Feeding SS as the roughage source decreased (P=0.01) G:F relative to BG. Hot carcass weight was greater (P < 0.01) for steers consuming 15 vs. 30% DG, tended to be least for diets with AH as the roughage source (P=0.06), and did not differ for the control vs. the other diets (P=0.86). Control cattle had an increased (P=0.05) proportion of USDA Choice or greater carcasses compared with the average of the other treatments. In Exp. 2, the same 2 × 3 +1 factorial arrangement as in Exp. 1 was used to examine the effects of roughage source and DG on IVDMD, culture fluid osmolality, and gas production kinetics. In vitro DMD tended (P < 0.09) to be greater for BG compared with SS at 6 and 36 h of incubation and was greater for AH vs. the mean of BG and SS at 18 h (P=0.01). Culture fluid osmolality, asymptotic maximal gas production, fractional rate of gas production, and lag time of gas production did not differ among treatments (P > 0.14). Overall, feeding 15% DG in SFC-based diets increased ADG, BW, and HCW relative to 30% DG. In addition, feeding AH tended to decrease ADG, final BW, and HCW relative to the other 2 roughage sources, whereas BG improved G:F over SS. These data suggest that including the smaller amount of DG and BG as the roughage source resulted in improved performance relative to other combinations, and that substituting roughages on the basis of equivalent NDF concentration might not be ideal for optimizing performance when feeding SFC-based finishing diets that contain DG.

Comparative feeding value of distillers dried grains plus solubles as a partial replacement for steam-flaked corn in diets for calf-fed Holstein steers: Characteristics of digestion, growth performance, and dietary energetics

“…Treatment effects on growth performance and dietary NE values are shown in Table 6. Consistent with previous studies evaluating DDGS substitution for SF corn in cross-bred beef breeds (Gordon et al, 2002;Uwituze et al, 2010;Quinn et al, 2011), there were no treatment effects (P ≥ 0.56) on DMI in calf-fed Holstein steers. During the initial 126-d period, when metabolizable AA supply is expected to be most limiting (NRC, 2000), increasing level of DDGS linearly increased (P = 0.03) ADG and increased quadratically (P ≤ 0.03) G:F, dietary NE, and observed/expected diet NE, with the response being maximal at 20% DDGS inclusion rate.…”

Interactive effects of bulk density of steam-flaked corn and concentration of Sweet Bran on feedlot cattle performance, carcass characteristics, and apparent total tract nutrient digestibility1

“…Analysis of acid insoluble ash, total starch, N, and OM were conducted on samples of diets, orts, and feces collected during the digestion phase as described by Ponce et al (2013). Neutral detergent fiber was determined using an Ankom 200 Fiber Analyzer (Ankom Technology, Macedon, NY) as described by Quinn et al (2011). Apparent total tract digestion of DM, OM, CP, NDF, and starch was calculated as follows: 100 -100 × [(AIA concentration in feed/AIA concentration in feces) × (nutrient concentration in feces/nutrient concentration in feed)].…”

Determining the optimal dietary roughage source and inclusion to decrease hydrogen sulfide in steers fed high-sulfur finishing diets

“…This suggests that feeding a balanced amount of starch and fiber in a supplement may provide the additional energy boost without decreasing rumen function and fiber utilization. in these studies (Uwituze et al, 2010;Quinn et al, 2011) suggest that roughage eNDF should also be taken in consideration when selecting roughage source to include in high concentrate diets. In a literature analysis conducted by , the data support the recommendations of Quinn et al (2011) and indicated that eNDF described the change in DMI more completely than total NDF.…”

“…in these studies (Uwituze et al, 2010;Quinn et al, 2011) suggest that roughage eNDF should also be taken in consideration when selecting roughage source to include in high concentrate diets. In a literature analysis conducted by , the data support the recommendations of Quinn et al (2011) and indicated that eNDF described the change in DMI more completely than total NDF. However, suggested eNDF may not be a practical measure for producers and may only separate roughage differences for certain roughages.…”

“…This low ruminal pH may inhibit NDF digestibility. Thus, it may be more effective at add roughage to the highly fibrous DDGS to optimize the digestion of fiber in both feedstuffs Quinn et al (2011). fed two ruminally cannulated Jersey crossbred steers (635 kg) a 60% SFC-based diet with ground alfalfa hay and collected ruminal fluid from both steers, which was blended together and utilized for the in vitro DMD experiment.…”