Wet Distillers Research Articles

Fermentation characteristics and feeding value of ensiled wet corn distillers grains in combination with wet beet pulp for lactating dairy cows

ABSTRACT Two experiments were conducted to evaluate (1) fermentation characteristics of ensiled wet corn distillers grains with solubles (WDG) and wet beet pulp (WBP) and (2) feeding value of ensiled blends of WDG and WBP in lactating dairy cow diets. On an as-fed basis, the ratio of ensiling for WDG:WBP was (1) 100:0 (DG100), (2) 67:33 (DG67), (3) 33:67 (DG33), and (4) 0:100 (DG0), respectively. Feedstuffs were ensiled and sampled at d 0, 4, 8, 21, and 112. Initial pH was lowest for DG100 and increased as the WBP was included. Low initial pH and increased acetic acid concentration with decreasing lactic acid concentration may have helped preserve both feedstuffs and their blends. Lactic acid was the predominant organic acid for DG100, and acetic acid was predominant at d 112 for the other 3 treatments. A feeding study followed the ensiling study. Nine cows (92 ± 4 DIM; mean ± SD) were used in a replicated 3 × 3 Latin square design. They were fed the (1) control diet; (2) low WDG diet with 21.7% DG33 blend (DM basis); and (3) high WDG diet with 24.6% DG67 blend (DM basis). There was no effect of diet on DMI. Milk yield was greater for cows fed WDG diets compared with cows fed the control diet; however, there was no effect of diet on energy-corrected milk. Milk fat concentration decreased for cows fed WDG diets compared with control diet; however, milk fat yield was not affected by diet. Cows fed WDG diets tended to produce milk with greater milk protein concentration and yield compared with cows fed the control diet, but there was no difference between WDG diets. Results provide evidence that ensiling WDG and WBP to preserve each wet by-product was possible and that ensiled blends could be incorporated in diets of lactating dairy cows to increase milk production and milk protein yield.

Investigating ruminant digestive characteristics of finishing beef steers fed sorghum wet distillers grains treated with calcium hydroxide

<h2>ABSTRACT</h2> Alkali treatment has been used to increase the digestibility of low-quality, fibrous crop residues. However, alkali treatment of the fiber fraction in distillers grains has only briefly been explored. Six ruminally cannulated steers (444 ± 4.0 kg of BW) were used to evaluate the effects of treating sorghum wet distillers grains plus solubles (SWDGS) with calcium hydroxide (CH) in finishing diets. Treatment diets were based on steam-flaked corn and included (1) 30% corn wet distillers grains plus solubles (CDG), (2) 30% SWDGS (SDG), or (3) 30% SWDGS treated with 2.27% CH (SDG-CH). Data were analyzed as a replicated Latin square with 3 dietary treatments and 3 periods using the MIXED procedure of SAS with animal within square as the experimental unit. No differences (<i>P</i> = 0.47) in DMI were observed. Steers consuming CDG had the greatest (<i>P</i> < 0.01) total ruminal VFA concentration, followed by SDG-CH, with SDG having the least. Steers consuming SDG had the greatest (<i>P</i> < 0.01) ruminal pH, followed by SDG-CH and then by CDG. Steers consuming SDG had the greatest (<i>P</i> < 0.01) ruminal acetate:propionate ratio, followed by SDG-CH, with CDG having the least. Steers consuming SDG-CH tended (<i>P</i> = 0.07) to have a greater apparent total-tract digestibility of NDF. No differences (<i>P</i> ≥ 0.15) were observed in apparent total-tract digestibility of DM, OM, ADF, starch, or N. Treating SWDGS with CH increased the digestibility of fiber compared with untreated SWDGS in finishing diets.

Modeling of effective moisture diffusivity and activation energy of distillers' spent grain pellets with solubles during superheated steam drying

Drying is an essential unit operation needed for safe storage and handling of the wet Distillers' spent grain (DSG), a major by-product of the ethanol industry. For the simulation and modeling of the drying process, a detailed study on different pre-requisite parameters such as the thermo-physical properties and effective moisture diffusivity of the material to be dried is required. The present study reports the effective moisture diffusivity and activation energy of the DSG pellets during superheated steam (SS) drying. Cylindrical DSG pellets at two moisture mass fractions (25 and 35%) and three mass fractions of distillers' solubles (0, 10, and 30%) were dried at three SS temperatures (120, 135, 150, 165, and 180 °C) and three SS velocities (0.5, 1.0, and 1.5 m/s), respectively. The experiment-based moisture diffusivity of the DSG pellet with and without solubles was determined by using the drying characteristic and the analytical solution of Fick's law of diffusion. The results showed that the effective diffusivity increased with an increase in SS temperature and velocity and its value was in the range of 2.49 × 10−9 to 17.9 × 10−9 m2/s. The dependency of the moisture diffusivity on temperature and moisture mass fraction was established by using Arrhenius equation and Levenberg-Marquardt optimization algorithm. The model coefficient and constants were compared with the calculated values of instantaneous effective moisture diffusivity with the mean relative percentage deviation ≤10%. These findings could serve as a fundamental input for the numerical modeling of SS drying of DSG.

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.

Effects of increasing dietary level of a commercial liquid supplement on growth performance and carcass characteristics in feedlot steers.

Feeding cattle liquid supplements has become increasingly popular in the feedlot industry; however, optimal inclusion of liquid supplements in feedlot cattle diets is not known. The objectives of this study were to determine the optimal inclusion of liquid supplementation to maximize growth performance and improve carcass characteristics, as well as estimate the energy value of liquid supplementation when used as a direct corn replacement, for feedlot steers fed a concentrate-based diet. Two hundred and eighty steer calves were stratified by BW into light (BW = 208 ± 9 kg; n = 24) and heavy (BW = 275 ± 8 kg; n = 16) pens. Pens within BW block were randomly assigned to 1 of 4 supplements: 1) dry at 4.5% inclusion (0LIQ), 2) liquid (a proprietary blend from Quality Liquid Feeds; Dodgeville, WI) at 4.5% inclusion (4.5LIQ), 3) liquid at 9% inclusion (9LIQ), or 4) liquid at 13.5% inclusion (13.5LIQ). The remainder of the diet was 47.5% to 55.5% dry rolled corn, 20% corn silage, and 20% modified wet distillers grains with solubles (DM basis). Data were analyzed as a randomized complete block design and linear and quadratic were examined to determine effects of increasing dietary concentrations of liquid. Steers fed 4.5LIQ and 9LIQ had greater (quadratic; P ≤ 0.05) final BW, HCW, and NEm and NEg, and less DMI as a percent of BW compared to steers fed 13.5LIQ. Steers fed 0LIQ were intermediate and not different from other treatments. However, ADG and total BW gain did not differ (P ≥ 0.15) among treatments. Despite the lack of treatment effect on live measures of gain, feeding steers 4.5LIQ and 9LIQ resulted in greater carcass ADG (quadratic; P = 0.03), total carcass gain (quadratic; P = 0.04), and more efficient carcass gain (quadratic; P ≤ 0.01) compared to carcasses from steers fed 13.5LIQ. Feeding steers a liquid supplement at 9% of the diet, DM allowed for the greatest final BW and ADG in this study; however, there was no benefit of increasing liquid to 13.5%.

Effect of Corn Processing and Wet Distiller’s Grains with Solubles on Odorous Volatile Organic Compound Emissions from Urine and Feces of Beef Cattle

Abstract. Wet distiller’s grains with solubles (WDGS) are a common feed ingredient in beef feedlot diets but the high nitrogen content of these diets creates air quality issues, primarily due to the aromatic compounds emitted during protein fermentation. Use of high moisture corn (HMC) instead of dry-rolled corn (DRC) in cattle feedlot diets has been shown to reduce some odors associated with excess starch in cattle feedlot diets. We hypothesized that using HMC in place of DRC in diets containing WDGS would reduce some of the odors associated with WDGS-DRC diets. A 4 × 4 replicated Latin square with a 2 × 2 factorial arrangement of treatments was used. Diets contained either DRC or a 2:1 ratio of HMC and DRC, with WDGS at either 25% or 45% of the diet dry matter resulting in four treatments: DRC-25, HMC-25, DRC-45 and HMC-45. Odorous compounds were measured from feces and urine of cattle fed the four diets. Feces from cattle fed diets containing 45% WDGS had a higher flux of p-cresol (9.42 µg m-3 min-1), 4-ethyphenol (0.04 µg m-3 min-1), and total aromatic compounds (13.56 µg m-3 min-1) compared to feces from cattle fed 25% WDGS (3.38, 0.03, and 6.86 µg m-3 min-1, respectively). Corn processing did not influence fecal odor flux. Urinary flux of odorous compounds was largely unaffected by corn processing method and only p-cresol (9.58 µg m-3 min-1), and total aromatic compounds (11.34 µg m-3 min-1) were higher for cattle fed 45% WDGS compared to cattle fed 25% WDGS (7.65 and 9.12 µg m-3 min-1, respectively for p-cresol and total aromatics). Overall there were no significant differences in odor potential, as determined by odor activity value (OAV), for cattle fed diets containing HMC and DRC with either concentration of WDGS. From these results, we interpret that producers may feed diets containing HMC or DRC in combination with WDGS at inclusion rates up to 45% with only minimal impacts of air quality. Keywords: Beef cattle manure, Distiller’s dried grain solubles, Dry-rolled corn, High-moisture corn, Odor, Volatile organic compounds.

Quality Effects of Beef from Cattle Fed High-Protein Corn Distillers Grains and Other Ethanol By-Products

ObjectivesThis research was conducted to evaluate the effects of feeding high protein corn distillers grains on beef tenderness during aging, sarcomere length, pH, proximate composition, and fatty acid compositionMaterials and MethodsSteers (n = 300) were fed for 190 d on either a corn control, 40% high protein dry distillers grains plus solubles (HP-DDGS), 40% dry distillers grains plus solubles (DDGS), 40% wet distillers grains plus solubles (WDGS), or 40% bran plus solubles (Bran) diet. Eighteen Choice carcasses (3 head/pen) were randomly selected within each treatment (n = 90). Strip loin samples from the right side were collected and aged for 2, 9, or 23 d. Steaks were fabricated at each aging period and placed under retail display conditions for 0 or 7 d. Tenderness (Warner-Bratzler shear force), sarcomere length, pH, proximate composition, and fatty acid composition were determined. Data were analyzed using the PROC GLIMMIX procedure of SAS (SAS Inst. Inc., Cary, NC) and pen was the experimental unit.ResultsHot carcass weight at harvest was 391 kg (SD 31.6 kg). Steaks aged 2 d showed no difference (P = 0.17) in tenderness across treatments, however a display effect (P < 0.0001) was present. Steaks that were under retail display conditions for 7 d exhibited a lower Warner-Bratzler shear force value than steaks not placed in retail display (3.40 kg and 4.27 kg, respectively). Steaks aged for 9 d and 23 d exhibited no differences across treatments (P = 0.14), however there was a significant age by treatment effect (P = 0.01). As HP-DDGS, DDGS, and Bran increased in aging an increase of tenderness was observed. There was no difference (P > 0.05) in tenderness between HP-DDGS and corn across aging periods. Retail display increased tenderness for steaks from 9 d and 23 d (P < 0.0001). No differences were observed among treatments for sarcomere length (P = 0.07), fat (P = 0.51), moisture (P = 0.71), or ash (P = 0.74). An aging effect was found for pH (P < 0.0001), however, the values were of little practical significance (5.49 23 d, 5.48 2 d, 5.44 9 d, respectively). Preliminary results suggest beef from cattle fed HP-DDGS had significantly higher (P = 0.03) levels of 18:2 in muscle than cattle fed corn (480.61 mg/100g vs. 272.49 mg/100g). All other treatments presented intermediate levels of 18:2 (395.92 mg/100g for DDGS, 350.06 mg/100g for WDGS, and 321.53 mg/100g for Bran). Cattle fed corn had significantly more (P = 0.03) 17:1 in their muscle when compared to Bran (85.51 mg/100g vs. 57.76 mg/100g).ConclusionThese results suggest that feeding high protein distillers grains have no detriment on tenderness, but may alter the lipid profile of the muscle.

Greenhouse Gas Emissions from Beef Feedlot Surface Materials as Affected by Diet, Moisture, Temperature, and Time

Abstract. A laboratory study was conducted to measure the effects of diet, moisture, temperature, and time on greenhouse gas (GHG) emissions from feedlot surface materials (FSM). The FSM were collected from open-lot pens where beef cattle were fed either a dry-rolled corn (DRC) diet containing no wet distillers grains with solubles (WDGS) or a DRC diet containing 35% WDGS. The FSM were collected, air-dried or mixed with 3.0 L of water to represent dry or wet conditions, and then incubated at temperatures of 5°C, 15°C, 25°C, or 35°C. Static flux chambers were used to quantify GHG emissions over a 14-day period. Flux data for each diet × moisture combination were analyzed using repeated measures in time. The largest GHG emissions occurred under wet conditions at temperatures of 25°C and 35°C. Flux values for these conditions typically were significantly greater than measurements obtained on the same day at 5°C and 15°C. Mean emissions under wet conditions for CO2, CH4, and N2O were 35, 121, and 278 times greater, respectively, than emissions from dry FSM. The 0% WDGS diet produced mean CO2 and N2O flux measurements that were 1.8 and 1.5 times greater, respectively, than those obtained for the 35% WDGS diet. The 35% WDGS diet, in contrast, produced a mean CH4 emission rate that was 6 times greater than the 0% WDGS diet. Management for GHG mitigation should include design and/or maintenance of pen drainage to speed drying as well as the use of modified animal diets. Keywords: Air quality, Carbon dioxide, Confined animal feeding operations, Drainage, Emission rates, Feedlot, Greenhouse gas, Methane, Nitrous oxide, Pen design.

Wet Distiller’s Grains and Wet Corn Gluten with Dry-Rolled or Whole-Shelled Corn in High-Energy Limit-Fed Diets Do Not Affect Growing Cattle Performance

Wet Distiller’s Grains and Wet Corn Gluten with Dry-Rolled or Whole-Shelled Corn in High-Energy Limit-Fed Diets Do Not Affect Growing Cattle Performance

Techno-economic evaluation of microwave drying of wheat distiller’s grain with solubles in Saskatchewan.

The incorporation of microwave drying system in industry-scale drying of wet wheat distillers grain with solubles (WDGS) was evaluated foreconomic viability under three scenarios: (i) microwave drying, where only microwave energy was used in reducing WDGS from 70% to 10% moisture on wet basis (w.b.); (ii) booster drying, where microwave energy was applied after rotary drying when drying rates began to fall; and (iii) finish drying, where microwave drying was used near the end of the drying process. Complete replacement of the conventional hot air drying system with microwave energy was not economically feasible under the present set of assumptions. Although energy requirement during microwave drying was substantially lower than that of rotary drying, the cost of electricity in providing the microwave energy was seen as a major hindrance. Lower electricity rates, availability of cheaper power sources, and attractive market incentives, such as premium prices for high protein quality wheat DDGS, may be necessary to encourage ethanol producers to invest in the technology. Finish drying, which used the least amount of electrical energy among the three scenarios, was seen as the more economically viable option. Costs associated with the other DDGS production processes also have to be assessed to have a more comprehensive picture of the costs and the benefits of investing on microwave drying technology for protein quality improvement.

Effects of bismuth subsalicylate and dietary sulfur level on fermentation by ruminal microbes in continuous culture.

In ruminants, excess dietary sulfur can be associated with a reduction in DM intake, poor feedlot performance and sulfur-associated polioencephalomalacia. Bismuth subsalicylate (BSS) has been shown to decrease hydrogen sulfide in vitro. The objective of this experiment was to evaluate effects of BSS inclusion (0 or 0.5% of diet DM) and dietary sulfur (0.21 or 0.42% of diet DM) on microbial fermentation in continuous culture. Treatments were arranged in a 2 × 2 factorial design. Eight dual-flow continuous culture fermenters were used during 2 consecutive 10-d periods consisting of 7 d for stabilization followed by 3 d of sampling. A pelleted feedlot diet containing 39% dry rolled corn, 32% earlage, 21% wet distillers grains, 3.2% corn silage, 1.5% soybean meal, 0.6% urea and 2.7% mineral premix (DM basis) was provided as substrate for microbes at a rate of 75 g of DM × fermenter–1 × d–1. Effluents from sampling days were composited by fermenter within period, resulting in 4 replicates/treatment. Bismuth subsalicylate inclusion decreased (P < 0.01) true OM digestion, while no effects were observed for NDF and ADF digestion. Total VFA concentrations, molar proportions of acetic, propionic, and branched-chained VFA decreased (P < 0.01) with BSS addition. The ratio of acetic to propionic acid and the molar proportion of butyric acid increased (P < 0.01) with BSS addition. In regard to nitrogen metabolism, BSS increased NH3–N concentration, NH3–N and dietary-N flows (P < 0.01), and decreased non-NH3–N flow, microbial-N flow, CP degradation, and efficiency of microbial protein synthesis (P < 0.01). Inclusion of BSS increased mean, minimum, and maximum fermentation pH (P < 0.01). Amount of dietary sulfur and BSS inclusion influenced flows of amino acids and fatty acids from fermenters. Influences on fatty acid biohydrogenation and amino acid flows demonstrated an overall suppression of microbial fermentation. Results from this experiment indicate that BSS inclusion at 0.5% of diet DM has detrimental effects on in vitro rumen fermentation in continuous culture.

Effects of finishing diets containing wet distillers grains plus solubles on beef quality attributes and fatty acid profile

The objective of this study was to evaluate the effects of feeding wet distillers grains plus solubles (WDGS) on quality attributes of three beef muscles (longissimus lumborum, psoas major, and infraspinatus). Ninety-six, yearlings crossbred steers were randomly assigned to one of three dietary treatments (Corn, 15%, or 30% WDGS - DM basis) and fed for 133 d. No significant differences were observed in marbling score (P=0.89), marbling texture (P=0.70), and marbling distribution (P=0.36). Greater concentrations of PUFA and lower levels of 18:1(n-7) were observed in beef from steers fed 30% WDGS when compared to other treatments. Lipid oxidation was also greater in beef from steers fed 30% WDGS (P≤0.05). No significant differences were observed in sensorial attributes and Warner-Bratzler shear force (WBSF) for all muscles (P>0.05). Feeding WDGS increased PUFA and lipid oxidation, which may lead to shorter shelf life.

Evaluation of Commercial β-Agonists, Dietary Protein, and Shade on Fecal Shedding of Escherichia coli O157:H7 from Feedlot Cattle.

Escherichia coli O157:H7 is a foodborne pathogen commonly associated with cattle feces. Diet, including dietary supplements such as β-agonists, may impact fecal shedding of this pathogen. A series of three experiments were conducted to determine if the β-agonists ractopamine hydrochloride (RAC) or zilpaterol hydrochloride (ZH) would impact the level or prevalence of fecal E. coli O157:H7 shedding. In Experiment 1, dietary RAC did not impact fecal shedding of E. coli O157:H7 based on the level or prevalence, but the addition of dietary soybean meal (SBM) in the study did reduce E. coli O157:H7 shedding. In Experiments 2 and 3, dietary ZH did not affect fecal E. coli O157:H7 shedding as determined by enumeration or prevalence, but in Experiment 2 the addition of 30% (dry matter basis) wet distillers grains with solubles (WDGS) in the diet tended to increase E. coli O157:H7 shedding. Shade is a potential management tool to reduce heat stress in cattle, and in Experiment 3 the presence of shade over the feedlot pens did not affect E. coli O157:H7 shedding. The use of β-agonists in cattle diets did not significantly affect fecal shedding of E. coli O157:H7, and in particular the percentage of animals shedding enumerable levels of the pathogen did not change, indicating that there was not a change in colonization. As has been reported previously and indicated again in this study, the use of WDGS in the diet may increase E. coli O157:H7 shedding. In contrast, the addition of SBM to cattle diets, to increase the dietary crude protein, appeared to reduce E. coli O157:H7 shedding, but this potential dietary intervention needs to be confirmed with additional research.

Feeding wet distillers grains plus solubles contributes to sarcoplasmic reticulum membrane instability

Feeding wet distillers grains plus solubles (WDGS) increases polyunsaturated fatty acid (PUFA) levels in beef. It was hypothesised that WDGS in feedlot diets increases PUFA concentration in the sarcoplasmic reticulum (SR) membrane, thereby altering membrane integrity, resulting in more rapid intracellular calcium leakage and improved tenderness. The objective of this study was to evaluate this hypothesis. Ninety-six crossbred steers were fed either a corn-based diet with 0% WDGS or 50% WDGS. Fifteen strip loins per treatment were collected, fabricated into steaks, aged and placed under retail display conditions. Steaks were used to measure tenderness, proteolysis, free calcium concentrations, lipid oxidation, sarcomere length and SR membrane fatty acid, phospholipid lipid, neutral lipid and total lipid profiles. Compared with steaks from steers fed 0% WDGS, steaks from steers fed 50% WDGS were more tender (P &lt; 0.05) and had greater (P &lt; 0.05) free calcium concentrations early post-mortem. Feeding 50% WDGS also tended to increase (P &lt; 0.10) total PUFA concentrations, decrease (P &lt; 0.10) total phospholipid concentration and increase (P &lt; 0.10) total neutral lipid concentration for SR membrane. Steaks from steers fed 0% WDGS had greater (P &lt; 0.05) lipid oxidation (TBARS values) than steaks from steers fed 50% WDGS after extended aging. Although differences in tenderness between the two treatments were detected, there were no corresponding differences (P &gt; 0.10) in sarcomere length or proteolysis. This study showed that feeding WDGS may increase tenderness, possibly by increasing free calcium in muscle early post-mortem. However, the true mechanism that contributes to these differences is still unclear.

Persistence of Escherichia coli O157:H7 and Total Escherichia coli in Feces and Feedlot Surface Manure from Cattle Fed Diets with and without Corn or Sorghum Wet Distillers Grains with Solubles

Feeding corn wet distillers grains with solubles (WDGS) to cattle can increase the load of Escherichia coli O157:H7 in feces and on hides, but the mechanisms are not fully understood. The objective of these experiments was to examine a role for the persistence of E. coli O157:H7 in the feces and feedlot pen surfaces of cattle fed WDGS. In the first study, feces from steers fed 0, 20, 40, or 60% corn WDGS were inoculated with E. coli O157:H7. The E. coli O157:H7 numbers in feces from cattle fed 0% corn WDGS rapidly decreased (P < 0.05), from 6.28 to 2.48 log CFU/g of feces by day 14. In contrast, the E. coli O157:H7 numbers in feces from cattle fed 20, 40, and 60% corn WDGS were 4.21, 5.59, and 6.13 log CFU/g of feces, respectively, on day 14. A second study evaluated the survival of E. coli O157:H7 in feces from cattle fed 0 and 40% corn WDGS. Feces were collected before and 28 days after the dietary corn was switched from high-moisture corn to dry-rolled corn. Within dietary corn source, the pathogen persisted at higher concentrations (P < 0.05) in 40% corn WDGS feces at day 7 than in 0% WDGS. For 40% corn WDGS feces, E. coli O157:H7 persisted at higher concentrations (P < 0.05) at day 7 in feces from cattle fed high-moisture corn (5.36 log CFU/g) than from those fed dry-rolled corn (4.27 log CFU/g). The percentage of WDGS had no effect on the E. coli O157:H7 counts in feces from cattle fed steam-flaked corn-based diets containing 0, 15, and 30% sorghum WDGS. Greater persistence of E. coli O157:H7 on the pen surfaces of animals fed corn WDGS was not demonstrated, although these pens had a higher prevalence of the pathogen in the feedlot surface manure after the cattle were removed. Both or either the greater persistence and higher numbers of E. coli O157:H7 in the environment of cattle fed WDGS may play a part in the increased prevalence of E. coli O157:H7 in cattle by increasing the transmission risk.

Impact of microbial efficiency to predict MP supply when estimating protein requirements of growing beef cattle from performance.

Data from 16 trials were compiled to calculate microbial CP (MCP) production and MP requirements of growing cattle on high-forage diets. All cattle were individually fed diets with 28% to 72% corn cobs in addition to either alfalfa, corn silage, or sorghum silage at 18% to 60% of the diet (DM basis). The remainder of the diet consisted of protein supplement. Source of protein within the supplement varied and included urea, blood meal, corn gluten meal, dry distillers grains, feather meal, meat and bone meal, poultry by-product meal, soybean meal, and wet distillers grains. All trials included a urea-only treatment. Intake of all cattle within an experiment was held constant, as a percentage of BW, established by the urea-supplemented group. In each trial the base diet (forage and urea supplement) was MP deficient. Treatments consisted of increasing amounts of test protein replacing the urea supplement. As protein in the diet increased, ADG plateaued. Among experiments, ADG ranged from 0.11 to 0.73 kg. Three methods of calculating microbial efficiency were used to determine MP supply. Gain was then regressed against calculated MP supply to determine MP requirement for maintenance and gain. Method 1 (based on a constant 13% microbial efficiency as used by the beef NRC model) predicted an MP maintenance requirement of 3.8 g/kg BW and 385 g MP/kg gain. Method 2 calculated microbial efficiency using low-quality forage diets and predicted MP requirements of 3.2 g/kg BW for maintenance and 448 g/kg for gain. Method 3 (based on an equation predicting MCP yield from TDN intake, proposed by the Beef Cattle Nutrient Requirements Model [BCNRM]) predicted MP requirements of 3.1 g/kg BW for maintenance and 342 g/kg for gain. The factorial method of calculating MP maintenance requirements accounts for scurf, endogenous urinary, and metabolic fecal protein losses and averaged 4.2 g/kg BW. Cattle performance data demonstrate formulating diets to meet the beef NRC model recommended MP maintenance requirement (3.8 g/kg S) works well when using 13% microbial efficiency. Therefore, a change in how microbial efficiency is calculated necessitates a change in the proposed MP maintenance requirement to not oversupply or undersupply RUP. Using the 2016 BCNRM to predict MCP production and formulate diets to meet MP requirements also requires changing the MP maintenance requirement to 3.1 g/kg BW.

Effects of dietary antioxidant supplementation of steers finished with 30% wet distillers grains plus solubles on fatty acid profiles and display life of strip loins

Feeding wet distillers grains plus solubles (WDGS) in beef feedlot diets increases beef polyunsaturated fatty acids (PUFA) concentration and decreases shelf-life; whereas feeding antioxidants like vitamin E and Agrado-Plus (AG; an ethoxyquin and tert-Butylhydroquinone mixture) mitigates such effects. The objective of this study was to evaluate shelf-life of beef from steers supplemented with WDGS and different antioxidants. One hundred and sixty steers were finished on a corn-based diet with 0% WDGS or 30% WDGS and four antioxidant treatments (no supplementation; vitamin E only; AG only; vitamin E + AG). Ten strip loins from each treatment were collected, aged, cut into steaks, and placed under retail display (2 ± 2°C). During retail display, steaks were evaluated daily for objective colour and subjective discolouration. After retail display, steaks were used to measure lipid oxidation, muscle fatty acids, and vitamin E and ethoxyquin concentrations. Feeding 30% WDGS increased total PUFA in beef when compared with beef from steers fed 0% WDGS (P &lt; 0.05). Supplementing vitamin E or vitamin E + AG was effective in decreasing myoglobin and lipid oxidation in steaks from steers fed 0% or 30% WDGS after retail display (P &lt; 0.01). Supplementation of vitamin E or AG also increased (P &lt; 0.01) muscle tissue vitamin E or ethoxyquin levels, respectively, compared with the diets without vitamin E or AG supplementation. The inclusion of 30% WDGS altered beef fatty acid profiles, but did not promote lipid and myoglobin oxidation compared with the 0% WDGS diet. Feeding vitamin E was effective, whereas supplementing AG had minor effects in decreasing myoglobin and lipid oxidation in steaks from both diet.

Roles of Graphene Oxide in Hydrothermal Carbonization and Microwave Irradiation of Distiller’s Dried Grains with Solubles To Produce Supercapacitor Electrodes

In this paper, we developed a facile, energy-efficient process for producing highly graphitized activated carbon (AC) using wet distiller’s dried grains with solubles (DDGS) as the feedstock. The three-step process included hydrothermal carbonization (HTC), KOH activation, and a short burst of direct microwave irradiation. We found that the presence of a small amount of graphene oxide (GO) in DDGS could significantly change the morphology of the produced carbon (from spherical particles to flakes) and increase the degree of carbonization and graphitization of the biomass. The AC produced with and without GO was made into supercapacitor electrodes, and their electrochemical properties were compared. This study proves that GO-assisted HTC and direct microwave irradiation is an effective method for biomass carbonization, and the AC produced using this method is a promising electrode material for supercapacitors.

Hourly methane production in finishing steers fed at different levels of dry matter intake1

Methane (CH) loss from finishing cattle is important as it represents an energy loss that could be used for maintenance and growth, and CH is a greenhouse gas with a global warming potential 21 to 25 times that of CO. Our objectives were to determine hourly CH production from growing cattle fed diets differing in corn processing method (dry rolling or steam flaking) and wet distillers grains with solubles (WDGS) inclusion rate. Eight steers (195 kg ± 2.3 in Exp. 1 and 322 kg ± 3.7 in Exp. 2) were fed the following diets: 1) steam-flaked corn (SFC)-based diet with 0% WDGS (SFC-0); 2) SFC-based diet with 15% WDGS (SFC-15); 3) SFC-based diet with 30% WDGS (SFC-30); 4) SFC-based diet with 45% WDGS (SFC-45); 5) Dry-rolled corn DRC)-based diet with 0% WDGS (DRC-0); and 6) DRC-based diet with 30% WDGS (DRC-30). All hourly CH data were analyzed using the MIXED procedure of SAS. Individual animal was the experimental unit. The model included the fixed effect of h, diet, and the h × diet interaction. Hourly differences in CH were analyzed using repeated measures. There were numerous h × diet interactions and thus simple-effect means are presented. In steers fed DRC-0 or DRC-30 at 2-times maintenance, the greatest hourly CH emissions occur 6 h after feeding ( < 0.01) with a secondary peak between 10 and 11 h after feeding ( < 0.01). For cattle fed SFC-0, SFC-15, SFC-30, and SFC-45 at 2-times maintenance, all diets had peak CH emissions 5 and 6 h after feeding ( < 0.01), with a secondary CH peak for SFC-45 nine to 11 h after feeding ( < 0.01). Cattle fed all diets at a maintenance level of intake exhibited 1 peak in hourly CH production between 3 and 6 h after feeding ( < 0.01). All steers fed SFC-30 and SFC-45 had sustained CH production over several hours, irrespective of intake level. Steers fed SFC-45 produced more CH beginning 4 h after feeding ( < 0.01) and produced a greater amount of CH than any other treatment ( < 0.01). Methane production generally peaked 6 h after feeding irrespective of intake level or diet type. Additionally, when fed above a maintenance level of intake, a secondary peak in CH production was observed 9 to 11 h after feeding, and steers fed at a maintenance level of intake had only 1 peak in CH production in a 23-h period.

266 Porcine in vitro digestion and fermentation characteristics of corn wet distiller's grains and distiller's dried grains with solubles without or with multicarbohydrase

266 Porcine in vitro digestion and fermentation characteristics of corn wet distiller's grains and distiller's dried grains with solubles without or with multicarbohydrase