Wet Distillers Grains Research Articles

Effects of increasing soybean hulls in finishing diets with wet or modified distillers grains plus solubles on performance and carcass characteristics of beef steers

Two experiments evaluated feeding soybean hulls (SBH) in finishing diets that contain distillers grains plus solubles on performance and carcass characteristics. Dietary concentrations of SBH were 0, 12.5, 25, and 37.5% of diet DM. In Exp. 1, 167 crossbred yearling steers (395 ± 22 kg of BW) were fed for 117 d in a randomized block design in which pelleted SBH replaced dry-rolled corn. All diets contained 25% modified distillers grains plus solubles, 15% corn silage, and 5% liquid supplement. As SBH concentration increased, DMI decreased linearly (P = 0.04). Gain and G:F decreased linearly (P < 0.01) in response to increasing concentrations of SBH, which decreased relative energy value from 91 to 79% of corn. Hot carcass weight linearly decreased (P < 0.01) by 24 kg as SBH increased. In Exp. 2, a randomized block design used 160 backgrounded steer calves (363 ± 16 kg of BW) in a 138-d finishing study with 0, 12.5, 25, or 37.5% SBH in the meal form. Basal ingredients consisted of a 1:1 ratio of high-moisture corn and dry-rolled corn, 40% wet distillers grains plus solubles, 8% sorghum silage, and 4% dry meal supplement. There was a tendency (P = 0.12) for a quadratic increase in ADG and G:F as dietary SBH increased, with numerically greatest ADG and G:F with 12.5% SBH. Feeding 12.5 to 25% SBH with 40% wet distillers grains plus solubles (Exp. 2) had little effect on performance but decreased ADG and G:F in diets with 25% modified distillers grains plus solubles (Exp. 1).

1471 Effect of corn wet distillers' grains inclusion in growing diets on backgrounded cattle performance

Distillers' grains (DG) can be used as energy as well as protein dietary sources. An experiment was conducted to evaluate the effect of partially replacing dry-rolled corn (DRC) and sunflower meal (SFM) with corn wet DG (WDG) in growing diets on cattle performance. One hundred ninety-two Angus calves (199 ± 3 kg initial BW) were assigned by weight to 1 of 3 blocks and group housed in 1 of 24 pens. Pens were randomly assigned to 1 of 4 diets containing (DM basis) 0% WDG, 19.4% DRC, and 20.4% SFM (CON); 10.0% WDG, 13.9% DRC, and 15.9% SFM (10-DG); 20.0% WDG, 8.0% DRC, and 11.8% SFM (20-DG); or 35.0% WDG, 0% DRC, and 4.8% SFM (35-DG). All diets contained 58.2% sorghum-sudangrass silage and 2.0% dry supplement. Diets were formulated to generate a RDP balance equal to zero and to meet or exceed MP requirements at expected ad libitum DMI and ADG. Dietary CP and lipid concentrations and IVDMD measured 12.0, 2.97, and 66.3%; 13.5, 4.00, and 66.8%; 15.1, 5.04, and 67.3%; and 17.3, 6.61, and 68.2% for CON, 10-DG, 20-DG, and 35-DG, respectively. Calves were fed once daily for 85 d and held off feed for 16 h to record initial and final individual BW. Data were analyzed as a generalized randomized complete block design. Cattle ADG was greater (P < 0.01) for calves fed the 20-DG diet (913 ± 20 g) compared with those fed the CON (682 ± 20 g) or 10-DG (829 ± 20 g) diets, although it was similar (P = 0.93) to those fed the 35-DG (915 ± 20 g) diet. Conversely, DMI was similar (P > 0.65) between cattle fed the CON (6.01 ± 0.27 kg/d), 10-DG (5.97 ± 0.27 kg/d), and 20-DG (5.93 kg/d) diets and smaller (P < 0.01) compared with cattle fed the 35-DG (5.41 ± 0.27 kg/d) diet. Consequently, G:F improved (P < 0.01) with increasing WDG dietary inclusion (114.4, 139.5, 154.2, and 169.6 ± 6.7 for CON, 10-DG, 20-DG, and 35-DG, respectively). Greatest lipid concentration in the 35-DG diet may have decreased fiber digestibility, which, in turn, could relate to reduced DMI. Additionally, ADG quadratic response (P < 0.01) may have resulted from greater NEg concentration and from DMI quadratic response (P < 0.01) with increasing WDG dietary inclusion. Including 35% WDG in a silage-based diet resulted in greatest G:F and growing-according ADG.

Effects of wet distillers grains with solubles in diets based on steam-flaked corn containing moderate or high roughage levels on nutrient digestibility in feedlot cattle and in vitro fermentation

ABSTRACT Previous research with roughage and wet distillers grains with solubles (WDGS) concentrations in feedlot diets based on steam-flaked corn has not extensively evaluated measurements of digestibility. Two experiments were conducted to evaluate the effects of concentrations of alfalfa hay (AH) and WDGS on apparent total-tract nutrient digestibility by finishing cattle and in vitro fermentation characteristics. In both studies, treatments were arranged in a 2 × 3 + 1 factorial and consisted of diets based on steam-flaked corn including AH (6 or 12% of DM) and WDGS (15, 30, or 45% of DM), and a control diet without WDGS that contained 9% AH. In Exp. 1, 56 beef steers (initial BW = 395 ± 7 kg) were used in a randomized complete block design and fed for 28 d. Intakes of DM, OM, NDF, ADF, and CP were greater (P ≤ 0.048) by steers fed 12 versus 6% AH. Increasing the dietary concentration of WDGS increased NDF, ADF, and CP intakes (P ≤ 0.046), and an AH × WDGS interaction (P ≤ 0.02) was detected for starch intake. Digestibility of DM and OM was greater for control steers than for the average of all treatments containing WDGS (P

Evaluation of Selected Nutrients and Contaminants in Distillers Grains from Ethanol Production in Texas

This article contains the results of the evaluation of distillers grain (DG) coproducts from different ethanol plants around the United States and supplemented in animal diets in Texas, based on samples analyzed from 2008 to 2014. The samples were assessed for concentration, occurrence, and prevalence of selected nutrients and contaminants. Protein and sulfur contents of DG were largely different between maize and sorghum coproducts, as well as wet distillers grain with solubles (WDGS) and dried distillers grain with solubles (DDGS), indicating a significant effect of grain feedstock and dry grind process stream on DG composition and quality. Salmonella was isolated in 4 DDGS samples of a total of 157 DG samples, a percentage (2.5%) that is lower than the percentage of Salmonella -positive samples found in other feed samples analyzed during the same period. A small amount of virginiamycin residue was found in 24 maize DDGS, 1 maize WDGS, and 2 sorghum DDGS samples of 242 samples in total. One sorghum DDGS sample of 168 DG samples was contaminated with animal protein prohibited for use in ruminant feed and was channeled to poultry feed. The concentrations of aflatoxin and fumonisin DG coproducts averaged 3.4 μg/kg and 0.7 mg/kg, respectively. Among contaminated maize DG samples, five DDGS samples for aflatoxin contained a higher concentration than the U.S. Food and Drug Administration (FDA) minimum action level of 20 μg/kg for use in animal feed, whereas no sample for fumonisin was found above the action level of 5 mg/kg. The study provides the most current results involving DG coproducts and associated hazards that will assist development of food safety plans required by the FDA in their September 2015 rule titled "Current Good Manufacturing Practice Hazard Analysis and Risk Based Preventive Controls for Food for Animals."

Distillers By-Product Cattle Diets Enhance Reduced Sulfur Gas Fluxes from Feedlot Soils and Manures.

Total reduced sulfur (TRS) emissions from animal feeding operations are a concern with increased feeding of high-sulfur distillers by-products. Three feeding trials were conducted to evaluate feeding wet distillers grain plus solubles (WDGS) on TRS fluxes. Fresh manure was collected three times during Feeding Trial 1 from cattle fed 0, 20, 40, and 60% WDGS. Fluxes of TRS from 40 and 60% WDGS manures were 3- to 13-fold greater than the 0 and 20% WDGS manures during the first two periods. In the final period, TRS flux from 60% WDGS was 5- to 22-fold greater than other WDGS manures. During Feeding Trial 2, 0 and 40% WDGS diets on four dates were compared in feedlot-scale pens. On two dates, fluxes from mixed manure and soil near the feed bunk were 3.5-fold greater from 40% WDGS pens. After removing animals, soil TRS flux decreased 82% over 19 d but remained 50% greater in 40% WDGS pens, principally from the wetter pen edges (1.9-fold greater than the drier central mound). During two cycles of cattle production in Feeding Trial 3, TRS soil fluxes were 0.3- to 4-fold greater over six dates for pens feeding WDGS compared with dry-rolled corn diet and principally from wetter pen edges. Soil TRS flux correlated with %WDGS, total N, total P, manure pack temperature, and surface temperature. Consistent results among these three trials indicate that TRS fluxes increase by two- to fivefold when cattle were fed greater levels of WDGS, but specific manure management practices may help control TRS fluxes.

Emission of Volatile Organic Compounds as Affected by Rate of Application of Cattle Manure

<abstract> Beef cattle manure can serve as a valuable nutrient source for crop production. However, emissions of volatile organic compounds (VOCs) following land application may pose a potential off-site odor concern. This study was conducted to evaluate the effects of land application method, N application rate, soil moisture content, and time since manure application on VOC emissions. Manure from cattle fed a diet containing 30% wet distillers grains was applied to a cropland area at rates required to meet the 0.5, 1, or 2 year N requirement for corn. Land application methods included surface-applying manure (i.e., no tillage) or incorporating manure using disk tillage. The effect of soil moisture content on VOC emissions was determined by adding water to the experimental plots approximately 24 h after manure application. Volatile sulfur compounds (i.e., dimethyl disulfide and dimethyl trisulfide), isovaleric acid, and butyric acid contributed 43.4%, 14.0%, and 13.9%, respectively, of the total measured odor activity value (OAV). Emissions of each of the principal VOC odor compounds were reduced by manure incorporation. In general, no significant differences in VOC measurements of volatile fatty acids (VFAs) and aromatic compounds were found among varying manure application rates. However, an increase in emissions of volatile sulfur compounds resulted from increased manure application. Measurements of VFAs and aromatic compounds usually decreased and sulfide emissions increased following the application of water. Application method, N application rate, soil moisture content, and time since application may all influence VOC emissions following land application of cattle manure.

The effect of process variables on drum granulation behavior and granules of wet distillers grains with solubles

A laboratory scale batch drum granulation process was used to manufacture granules of DDGS by adding condensed distillers solubles (CDS) as a binder to wet distillers grains (WDG), coproducts from corn dry-grind ethanol process, under varying formulation and process conditions. A full factorial experimental design was used to test all combinations of factor levels, which included the amount of CDS binder (30%, 35%, and 40% (w/w)), CDS binder solids content (22% and 38%, wet basis), screen size opening (3.175 and 6.35mm), and residence time (1, 2.5, 5, and 10min). Measured response variables included granule size (geometric mean diameter), granule yield (1.68–3.35mm), bulk density, true density, and porosity. Results show that as the amount of binder added increased from 30% to 40% the granule size significantly increased from 2.08 to 4.45mm, respectively. Increasing the binder solids content resulted in granules with greater bulk density. Granules produced from the low solids CDS had lower porosity as a result of intraparticle voids in them. Screen sizing influenced nucleation and produced significant differences in the final granule size distribution. The greatest growth was observed for granules prepared with 40% amount of binder and low solids content CDS. Compression testing of wet granule compacts corresponded to observed growth behavior; wet pellets made from higher solids CDS had greater resistance to deformation and enhanced plasticity while the opposite was observed for the low solids CDS. The best yields of granules between 1.68 and 3.35mm were achieved at ∼80% using 35% amount of binder with the high solids content CDS, the small screen size opening and residence times between 2.5 and 10min.

Ensiling quality of maize as influenced by the addition of wet distillers grains with soluble

Wet distillers grains with soluble (WDGS) were blended with whole maize plants on an as-fed basis at 0%, 20%, 30%, and 40% and ensiled in 3 L bottles to evaluate the silage fermentation characteristics and ensiling quality in a complete randomized design. Each treatment was ensiled in 15 mini-silos and three bottles were opened on days 7, 21, 42 and 120. Each treatment was sampled for chemical composition and silage fermentation parameters. There was a steady decrease in dry matter (DM) concentration of silage with increasing WDGS inclusion level over time. Initial pH (at day 0) decreased with increasing level of WDGS inclusion, with 40% WDGS inclusion recording the lowest pH (3.6) at day 120. Lactic acid concentration was slightly lower for WDGS-blended silages compared with the control. In contrast, the acetic acid concentration for WDGS-blended silage increased across all treatments, suggesting a possible diminished effect of clostridium bacteria in the silage owing to a reduced pH. The acid detergent fibre (ADF), neutral detergent fibre (NDF) and IVDOM (in vitro digestible organic matter) did not differ at the time of ensiling among treatments. During post ensiling, ADF increased slightly over time for WDGS-blended treatments (at 120 days). The results from this study indicated that WDGS could be ensiled effectively with maize plants without compromising silage quality.

103 Effects of treating sorghum wet distillers grains plus solubles with calcium hydroxide in steam-flaked corn-based finishing diets on dry matter intake and ruminal fermentation characteristics

103 Effects of treating sorghum wet distillers grains plus solubles with calcium hydroxide in steam-flaked corn-based finishing diets on dry matter intake and ruminal fermentation characteristics

Influence of feeding increasing levels of dry or modified wet corn distillers grains plus solubles in whole corn grain-based finishing cattle diets on pancreatic α-amylase and trypsin activity

The objectives of this study were to determine the effect of dietary inclusion [0%–50% of diet dry matter (DM)] and form (dry and modified wet) of corn distillers grains plus solubles (DGS) on pancreatic α-amylase and trypsin activities in calves. Feeding up to 50% DGS did not negatively impact pancreatic exocrine function.

The effects of dry-rolled corn particle size on performance, carcass traits, and starch digestibility in feedlot finishing diets containing wet distiller's grains.

Crossbred yearling steers ( = 360; 395 ± 33.1 kg initial BW) were used to evaluate the effects of dry-rolled corn (DRC) particle size in diets containing 20% wet distiller's grains plus solubles on feedlot performance, carcass characteristics, and starch digestibility. Steers were used in a randomized complete block design and allocated to 36 pens (9 pens/treatment, with 10 animals/pen). Treatments were coarse DRC (4,882 μm), medium DRC (3,760 μm), fine DRC (2,359 μm), and steam-flaked corn (0.35 kg/L; SFC). Final BW and ADG were not affected by treatment ( > 0.05). Dry matter intake was greater and G:F was lower ( < 0.05) for steers fed DRC vs. steers fed SFC. There was a linear decrease ( < 0.05) in DMI in the final 5 wk on feed with decreasing DRC particle size. Fecal starch decreased (linear, < 0.01) as DRC particle size decreased. In situ starch disappearance was lower for DRC vs. SFC ( < 0.05) and linearly increased ( < 0.05) with decreasing particle size at 8 and 24 h. Reducing DRC particle size did not influence growth performance but increased starch digestion and influenced DMI of cattle on finishing diets. No differences ( > 0.10) were observed among treatments for any of the carcass traits measured. Results indicate improved ruminal starch digestibility, reduced fecal starch concentration, and reduced DMI with decreasing DRC particle size in feedlot diets containing 20% wet distiller's grains on a DM basis.

Characteristics of Wet Distillers Grains on In vitro Ruminal Fermentation and Its Effects on Performance and Carcass Characteristics of Finishing Hanwoo Steers.

Two experiments were conducted to determine the nutrient composition, in vitro ruminal ammonia concentrations and pH of wet distillers grains (WDG, produced from tapioca 70% and rice 30%) and to evaluate dietary effects of fermented total mixed ration (TMR) using WDG on the performance, blood metabolites and carcass characteristics of Hanwoo steers from mid fattening to slaughter. In Exp. I, average dry matter (DM), crude protein, ether extract, crude fiber, ash, neutral detergent fiber, acid detergent fiber, and nitrogen free extract of seven WDG samples from an ethanol plant with different sampling dates were 19.9%, 24.8%, 3.8%, 21.8%, 8.87%, 60.3%, 34.5%, and 40.7% (DM basis), respectively. For in vitro ammonia concentrations and pH, each sample was assigned to 7 incubation times (0, 4, 8, 12, 24, 48, and 72 h). Linear increase was observed between 12 and 48 h for ammonia concentrations, but final ammonia concentrations (72 h) were not significantly different among WDG samples and fermentation patterns of WDG samples showed similar tendency. In vitro pH varied among treatments from 0 to 24 h, but were not different statistically after 48 h. In Exp. II, 45 Hanwoo steers of 23 months (641±123 kg) from mid fattening period to slaughter (248 days) were randomly divided into three groups of 15 pens each (five repetitions/each treatment) and assigned to one of three dietary treatments; i) Control (TMR), ii) WDG 15 (TMR containing 15% of WDG, as fed basis) and iii) WDG 28 (TMR containing 28% of WDG, as fed basis). The body weight (BW), ADG, and feed conversion ratio (FCR) of control and WDG 15 and 28 during 248 days were 760.8, 740.1, and 765.5 kg, and 0.50, 0.50, and 0.52 kg/d, and 18.6, 17.6, and 17.1, respectively. The dry matter intake (DMI) (kg/d) of control (9.11) was higher (p<0.05) than WDG treatments (WDG 15%, 8.57; 28%, 8.70). Nevertheless, DMI did not affect BW, ADG, and FCR of Hanwoo finishing steers. Blood metabolites were in normal ranges and were not different among treatments except the albumin concentration. In carcass characteristics, WDG 15 (30%) showed higher frequency of A-carcass yield grade than WDG 28 (15%) and control (7%), and WDG 28 (61%) showed higher frequency of 1++ and 1+-carcass quality grade than WDG 15 (40%) and control (60%). In conclusion, using WDG up to 28% in TMR did not show any negative effect on the performance and blood metabolites, and improved carcass quality of Hanwoo steers. Therefore, WDG can be a useful feed ingredient for Hanwoo steers in mid-fattening period to slaughter.

Feeding wet distillers grains plus solubles with and without a direct-fed microbial to determine performance, carcass characteristics, and fecal shedding of O157:H7 in feedlot heifers.

The inclusion of wet distillers grains plus solubles (WDGS) in feedlot diets has become a common practice in many regions of the United States due to the expanded production of byproducts and fluctuating corn prices related to ethanol production and other factors. In addition, societal concerns over the continued use of antimicrobials in agriculture production combined with an enhanced interest in disease and pathogen prevention in the food supply have led to an increased interest in use of direct-fed microbials (DFM) in growing and finishing cattle. Direct-fed microbials have been shown to improve ADG and feed efficiency, alter ruminal fermentation, and decrease fecal shedding of potential harmful pathogens in feedlot cattle in some experiments. The objective of this experiment was to evaluate the effects of WDGS inclusion with or without a DFM containing (1 × 10 cfu ∙ heifer ∙ d) combined with (1 × 10 cfu ∙ heifer ∙ d) on the performance, carcass characteristics, and O157:H7 shedding in feedlot heifers. In early August, 288 crossbred heifers (initial BW = 295 ± 28 kg) were assigned to 1 of 4 treatments (12 pens per treatment; 6 heifers per pen) in a randomized complete block design with a 2 × 2 factorial arrangement of treatments. Body weights and fecal grab samples were obtained at approximately 28-d intervals throughout the experiment. Across the feeding period, heifers fed 30% WDGS tended ( = 0.09) to have greater ADG and had greater carcass-adjusted ADG ( = 0.05) compared with heifers fed dry-rolled corn (DRC). Dry matter intake was not affected ( = 0.65) by diet, although carcass-adjusted G:F tended ( = 0.10) to be improved for heifers fed WDGS. Heifers fed 30% WDGS tended ( ≤ 0.10) to have greater fat thickness at the 12th rib, lower marbling scores, and higher yield grades. The inclusion of . combined with . in the diet had no effect ( > 0.10) on performance or carcass merit in the present experiment. The incidence of O157:H7 throughout the experiment was low, with only 18 positive samples across all sampling periods. Neither WDGS inclusion nor the inclusion of . combined with . in the diet had any effect ( > 0.10) on O157:H7 shedding in this experiment. Feeding 30% WDGS to feedlot heifers improved animal performance compared to the DRC-based control diet.

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

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

Effect of corn particle size with moderate amounts of wet distillers grains in finishing diets on starch digestibility and steer performance

Five hundred yearling steers (370 ± 30.0 kg, SD) were used to determine the effect of corn particle size in diets containing 35% wet distillers grains plus solubles (WDGS) on steer performance, carcass characteristics, and apparent total-tract starch digestibility (TTSD). Treatments included 45% cracked corn (CON; 2,350 μm) or finely ground corn (FIN; 500 μm) with 35% WDGS and were replicated in 4 pens per treatment with 60 or 64 steers per pen. Fecal samples were collected on d 71 and 72 (F-1) and d 102 and 103 (F-2). Final BW and HCW were heavier (P ≤ 0.01) for steers finished on CON compared with steers finished on FIN. Whereas G:F was not different (P = 0.22) between treatments, DMI and ADG were greater (P ≤ 0.01) for CON-fed steers than FIN-fed steers. Liver abscess scores were not influenced (P ≥ 0.39) by treatment. Liver abscess scores tended (P = 0.10) to influence ADG over the experiment, with steers having severe liver abscess scores gaining less compared with steers with no or mild liver abscess scores. A treatment × time effect (P < 0.01) was observed for TTSD. Whereas TTSD of steers fed CON decreased over time (90.28 and 85.74% for F-1 and F-2, respectively), TTSD of steers finished on FIN did not differ across the 2 sampling dates (97.95 and 97.55% for F-1 and F-2, respectively). Apparent starch digestibility was improved for steers fed finely ground corn with 35% WDGS; however, cattle performance was less compared with steers fed cracked corn with 35% WDGS.

Thermophysical properties of laboratory-prepared corn/wheat dried distillers grains and dried distillers solubles dehydrated with superheated steam and hot air

ABSTRACTThe objective of this study was to dry–wet distillers grains and centrifuged solubles and to examine the effect of two different drying media, superheated steam and hot air, at different drying temperatures (110, 130, and 160°C), moisture contents (5–30% wb), and percentages of solubles’ presence (0 or 100%) on some thermophysical properties of laboratory-prepared corn/wheat dried distillers co-products, including geometric mean diameter (dg), particle density (ρp), bulk density (ρb), bulk porosity (ϵb), specific heat (C), effective thermal diffusivity (αeff), and bulk thermal conductivity (λb). The values of dg of corn/wheat dried distillers co-products ranged from 0.358 ± 0.001 to 0.449 ± 0.001 mm. Experimental values of ρp, ρb, and ϵb varied from 1171 ± 6 to 1269 ± 3 kg m−3, from 359 ± 7 to 605 ± 5 kg m−3, and from 0.54 ± 0.01 to 0.71 ± 0.01 kg m−3, respectively. The values of αeff were between 0.58 × 10−7 and 0.93 × 10−7 m2 s−1. The calculated values of C ranged from 1887 ± 11 to 2599 ± 19 J kg−1 K−1, and the values of λb of corn/wheat dried distillers co-products ranged from 0.06 ± 0.01 to 0.09 ± 0.01 W m−1 K−1. Multiple linear regression prediction models were developed to predict the changes in dg, ρp, ρb, ϵb, C, αeff, and λb of laboratory-prepared corn/wheat dried distillers co-products with different operational factors.

Ensiling characteristics of distillers wet grains with corn stalks and determination of the feeding potential for dairy heifers

ABSTRACT The characteristics and feeding potential of corn distillers wet grains with solubles ensiled with corn stalks were evaluated in a 2-part experiment. Six individual batches of 66.7% distillers wet grains with solubles and 33.3% corn stalks (on an as-fed basis) were mixed and ensiled in 2 plastic silage bags. A set of 3 batches was left untreated (UNT), and the other set of 3 batches was treated (TRT) with a silage additive. Silos were sampled for analysis on d 0, 7, 14, and 21 after ensiling. The ensiling study was followed by a 6-wk randomized complete block design feeding study using 12 dairy heifers (initial BW of 213.8 ± 3.03 kg) with 3 diets. Treatment diets were (1) control (CON) consisting of 30.3% grain mixture and 69.7% alfalfa and orchard grass hay, (2) 99% UNT blend and 1% mineral premix, and (3) 99% TRT blend and 1% mineral premix on a DM basis. In the ensiling study, blends were similar in DM, CP, ADF, pH, lactic acid, and acetic acid. In the feeding study, body frame measurements and ADG were similar among heifers fed all diets. Dry matter intakes were greater and G:F was less (P

Effects of feeding processed corn stover and distillers grains on growth performance and metabolism of beef cattle.

Objectives were to evaluate the effects of replacing corn in feedlot finishing diets with processed corn stover (CS), processed by various combinations of chemical and physical methods, and modified wet distillers grain with solubles (MWDGS) on growth performance, carcass characteristics, digestibility, and ruminal metabolism of cattle. Corn stover was physically processed (ground or extruded) and chemically processed with alkaline agents (CaO and NaOH) to reduce the crystallinity of the lignocellulosic structure. In Exp. 1 steers ( = 18, initial BW = 385 ± 32 kg) and heifers ( = 41, initial BW = 381 ± 27 kg) were allotted to 1 of 5 dietary treatments: 1) 55% dry, cracked corn, 35% MWDGS, 5% vitamin-mineral supplement, and 5% untreated ground CS (), 2) CS treated with 5% CaO (DM basis) and stored in an Ag-Bag (BGCS), 3) CS treated with 5% CaO (DM basis) and extruded (5 EXCS), 4) CS treated with 4% CaO and 1% NaOH (DM basis) and extruded (4,1 EXCS), or 5) CS treated with 3% CaO and 2% NaOH (DM basis) and extruded (3,2 EXCS). Extruded CS was hydrated to 34% moisture, then an additional 16% water was added, as a solution carrying CaO or NaOH or both, via a calibrated pump during processing through a dual-shafted encased extruder (Readco Kurimoto Continuous Processor, York, PA) with the desired exiting temperature of 76.7°C ± 2.8°C. All treated CS diets contained 20% CS and 40% MWDGS (DM basis) to replace 20% corn when compared to CON. There were no effects ( ≥ 0.20) of dietary treatment on ADG, G:F, 12th-rib back fat, marbling score, LM area, or yield grade. However, cattle fed CON had increased ( = 0.02) DMI compared to cattle fed the treated CS diets. In Exp. 2, using the same diets as fed in Exp. 1, ruminally cannulated steers ( = 5; initial BW = 417 ± 21 kg) were fed for 90% of ad libitum intake in a 5 × 5 Latin square design. Apparent digestibility of NDF and ADF increased ( < 0.01) when cattle were fed treated CS diets compared with CON, regardless of the treatment applied. Ruminal pH was reduced ( = 0.02) in cattle fed BGCS from 0 to 6 h postfeeding compared with cattle fed all other diets. Cattle fed the treated CS diets had the greatest ( < 0.01) mean acetate concentrations, which increased ( = 0.01) total VFA concentrations. Replacing a portion of the corn with treated CS in feedlot diets containing MWDGS increased fiber digestibility without affecting feedlot cattle gain, efficiency, marbling score, or LM area.

Rumen microbiome from steers differing in feed efficiency.

The cattle rumen has a diverse microbial ecosystem that is essential for the host to digest plant material. Extremes in body weight (BW) gain in mice and humans have been associated with different intestinal microbial populations. The objective of this study was to characterize the microbiome of the cattle rumen among steers differing in feed efficiency. Two contemporary groups of steers (n=148 and n=197) were fed a ration (dry matter basis) of 57.35% dry-rolled corn, 30% wet distillers grain with solubles, 8% alfalfa hay, 4.25% supplement, and 0.4% urea for 63 days. Individual feed intake (FI) and BW gain were determined. Within contemporary group, the four steers within each Cartesian quadrant were sampled (n=16/group) from the bivariate distribution of average daily BW gain and average daily FI. Bacterial 16S rRNA gene amplicons were sequenced from the harvested bovine rumen fluid samples using next-generation sequencing technology. No significant changes in diversity or richness were indicated, and UniFrac principal coordinate analysis did not show any separation of microbial communities within the rumen. However, the abundances of relative microbial populations and operational taxonomic units did reveal significant differences with reference to feed efficiency groups. Bacteroidetes and Firmicutes were the dominant phyla in all ruminal groups, with significant population shifts in relevant ruminal taxa, including phyla Firmicutes and Lentisphaerae, as well as genera Succiniclasticum, Lactobacillus, Ruminococcus, and Prevotella. This study suggests the involvement of the rumen microbiome as a component influencing the efficiency of weight gain at the 16S level, which can be utilized to better understand variations in microbial ecology as well as host factors that will improve feed efficiency.

The effect of storage temperature and percentage of condensed distillers solubles on the shelf-life of distillers wet grains stored aerobically

Distillers wet grains with solubles (DWGS) are widely used as a supplemental protein source in North American cattle rations. However, due to its short shelf-life, its use is limited to feedlots within close proximity of an ethanol production plant. It is known that the shelf-life of DWGS in the summer diminishes drastically compared to in the winter. This effect is primarily due to temperature, which drives mold growth in high moisture feedstocks. The purpose of this study was to understand and quantify the effect of temperature (10, 20, and 25 °C) and condensed distillers solubles (CDS) levels [0%, 20% and 30%] on the shelf-life of DWGS under warm and cool aerobic storage conditions. Sample conditions which indicate shelf-life and product deterioration such as moisture content (m.c.), pH, fat acidity (FA), fungal growth and mycotoxin levels were measured in the DWGS samples before and after seven days of storage under three temperature levels (10, 20, and 25 °C). It was found that changes in temperature had the most significant effect on sample conditions (P < 0.05). After seven days of storage, m.c. and water activity (aw) decreased with increase in temperature. In comparison, it was determined that FA, pH, fungal growth and mycotoxin levels increased with temperature after seven days of storage. Also, FA and CFU increased with increase in CDS level in DWGS. It was concluded that after seven days of storage at both warm and cool aerobic storage conditions, FA, aflatoxin, fumonisin and zearalenone levels increased. DWGS deteriorated less at 10 °C than at 20 °C and 25 °C, likewise less deterioration in 0% CDS than in 20% and 30% was noted.