Wet Distillers Research Articles

199 Inclusion of Sweet Bran™ and wet distillers grains alone or in combination improves performance, carcass merit, and rumen buffering characteristics of feedlot cattle fed steam-flaked corn diets

Abstract This study evaluated the effects of Sweet Bran™ (SB) and/or wet distillers grains with solubles (WDGS) in the diet alone or in combination on performance, carcass characteristics, ruminal pH, and rumination of finishing beef cattle. Steers (n = 455) were randomly allocated to 48 pens and assigned to 1 of 4 steam-flaked corn-based dietary treatments containing: no byproducts (CON), 20% WDGS (WDGS), 20% SB (SB), or 20% SB and 10% WDGS (COMBO). Within each pen, 2 steers were randomly selected to receive a ruminal pH bolus and ear tag to quantify pH and rumination. Diet samples were collected weekly to determine particle size and physically effective fiber. Final BW, DMI, and ADG were greater (P < 0.01) for WDGS, SB, and COMBO than CON. Hot carcass weight was greatest (P = 0.04) for WDGS and SB, intermediate for COMBO, and least for CON. Yield grade tended (P = 0.09) to be greater for WDGS, SB, and COMBO than CON. A numerical increase in abscessed livers was observed for CON. The percentage of particles > 4 mm was greatest (P < 0.01) for CON, intermediate for SB, and least for WDGS and COMBO. However, NDF (P < 0.01) and peNDF (P < 0.01) were greatest for COMBO, intermediate for WDGS and SB, and least for CON. A treatment × time interaction was observed as CON cattle spent less time ruminating at 0800 and 1000 h (P < 0.01) in a 24h period. Ruminal pH was least (P < 0.01) for CON from 0800 to 1800 h. Addition of WDGS and/or SB improved performance and reduced feed cost of gain when incorporated into steam-flaked corn-based finishing diets. Relationships between peNDF, rumination behavior, and ruminal pH suggest that SB and/or WDGS enhance buffering capacity when steam-flaked corn is replaced in the diet.

192 Abundance of rumen methanogens did not differ in cattle that differed in residual feed intake

Abstract Methane represents an energetic loss, and it has been proposed that its reduction may be associated with improved feed efficiency. Rumen methanogens produce most of the methane. Forty-nine crossbred heifers were individually fed a ration that consisted of 67.75% rolled corn, 20% wet distillers grain with solubles, 8% chopped alfalfa and 4.25% mineral/vitamin/rumensin mix for 84 d. Residual feed intake was the residual of the observed – predicted FI for the multivariate regression of FI on ADG and mid-metabolic BW for the population. Six heifers with the greatest RFI (1.75 ± 0.31 kg DM/d) and 6 with least RFI (-1.48 ± 0.31 kg DM/d) were selected. Rumen fluid was sampled from a tube passed through the mouth into the rumen. Rumen fluid was flash frozen in liquid N2 and stored at -80°C. After the first collection, heifers with greater RFI were pair fed to the less RFI heifers and rumen fluid was sampled 5 wk later. DNA was isolated from the rumen fluid and primer sets targeting total methanogens, Methanomicrobiales, Methanobacteriales, Methanosarcina, Methanobacterium, Methanobrevibacter ruminantium + Mbb. Cuticularis, and Methanobrevibacter smithii + Mbb. wolinii + Mbb. thaueri + Mbb. gottschalkii + Mbb. Woesei were amplified with real-time quantitative PCR (qPCR). Standard curves were generated to quantify copy number. There were no differences in copy number for the interaction of RFI classifications and sample period for all primer sets (P > 0.18). There were no differences in (P > 0.15) in RFI classification for all qPCR primer sets. There were fewer copies for the Methanobrevibacter ruminantium + Mbb. Cuticularis qPCR for samples collected in the first week compared to the 5 wk sample (P = 0.03); however, there were no difference for collection week for the other qPCR assays (P > 0.16). USDA is an equal opportunity provider and employer.

251 Evaluation of Condensed Algal Residue Solubles as an Ingredient in Cattle Finishing Diets

Abstract Algae oil production for Omega-3 fatty acid supplementation yields a byproduct called Condensed Algal Residue Solubles (CARS; 25.4% DM, 19.3% CP, 8.3% Fat, 9.96% Na on DM basis), de-oiled algae cells with residual fermentation substrates. This study evaluated the use of CARS in feedlot finishing diets. Crossbreed steers, (n=480) were blocked and stratified by initial body weight (BW) into 4 blocks, and assigned randomly to treatments. Treatments were designed as a 2 x 3 factorial with 3 inclusions of CARS (0, 2.5, 5% of diet DM) and 2 different base diets representing Northern and Southern Great Plains diets. The Southern diets contained steam flaked corn and dry distillers grains while the Northern diets had dry rolled and high moisture corn with wet distillers grains. CARS replaced corn in both diets. All blocks were harvested after 148 days on feed. Performance data were analyzed as a randomized block design with CARS inclusion, base diet, and interactions as fixed effects, BW block as a random effect and pen (n=48) as the experimental unit. Orthogonal contrasts were used to test linear and quadratic effects of CARS inclusion. There were no significant interactions between CARS inclusion and diet type (P ≥ 0.49). Main effects of CARS indicated positive quadratic responses for carcass adjusted ADG, G:F, 12th rib back fat, yield grade (P < 0.01; increasing to 2.5% inclusion, decreasing at 5%) and hot carcass weight was both linear and quadratic (P ≤ 0.01 and P ≥ 0.06 respectively; 969, 977, 935 as CARS increased). Linear decrease in DMI, final adjusted BW and ribeye area (P ≤ 0.01) as CARS increased. Cattle fed the Southern diets had greater ADG and G:F compared to Northern diets (P < 0.01). Including 2.5% CARS in the diet improved feed efficiency in both Northern and Southern based feedlot diets.

PSI-10 Effects of a Moderate and Aggressive Implant Strategy on the Rumen Microbial Community in Steers

Abstract The effects of growth-promoting implant strategies have been well-defined in research for their ability to impact growth performance in beef cattle. Production-relevant microbiomes in the rumen have also been associated with growth traits. However, the role of implant strategies on the rumen microbiome is not understood. The objective was to determine if varying doses of implant hormones cause gain-associated ruminal microbial community shifts. To assess this, a completely randomized design was used and 336 fall-born steers from the germplasm evaluation population between 450–470 days of age at the U.S. Meat Animal Research Center (Clay Center, NE) were divided into two treatment groups: 1) a moderate implant strategy of Revalor-IS (80 mg trenbolone acetate, 16 mg estradiol) followed by Revalor-S (120 mg trenbolone acetate, 24 mg estradiol) and 2) an aggressive implant strategy of Revalor-IS followed by Revalor-200 (200 mg trenbolone acetate, 20 mg estradiol). Steers were fed the same diet (57.0% dry-rolled corn, 30% wet distiller’s grains with solubles, 8.0% alfalfa hay, 4.25% supplement, and 0.75% urea, DM basis). Body weights were collected once per month with initial weights of 439.8 ± 43.1 kg. After implants were administered for 84 days, rumen content was collected via orogastric tubing. Samples were sequenced targeting bacterial V1-V3 16S rRNA gene regions, V3-V4 for archaea, and partial 18S rRNA gene of protozoa. Sequences were processed in R utilizing Phyloseq and analyzed with DESeq2 to test differential abundances. Production data between implant strategies were analyzed using a mixed model ANOVA (SASv9.4, Cary, NC). Alpha- and beta-diversity between strategies did not differ for bacteria, archaea, or protozoa (P > 0.05). Average daily gain was different (P = 0.01; 1.72 vs 1.66 ± 0.02 kg, aggressive vs moderate, respectively); however, large microbial community shifts were not associated implant strategy. USDA is an equal opportunity provider and employer.

408 WS Distinguished Service Talk: Effects of steam flaking on the carbon-footprint of finishing beef cattle

Abstract Grain processing has been used for many decades to improve the digestibility of feed grains fed to finishing beef cattle and to improve animal performance. The most common methods currently used by feedyards in the U.S. are dry rolling (DRC) and steam flaking (SFC). However, the environmental effects of gain processing have not been rigorously studied. This manuscript presents a comparative estimate of the carbon footprint of steam flaking corn in beef cattle finishing diets with and without wet distiller’s grains with solubles (WDGS). Estimates were based on results of published literature and the Intergovernmental Panel on Climate Change. Although SFC required more natural gas and electricity for processing than DRC, feeding SFC decreased the total carbon-footprint by 9 to 13 % per steer. This was primarily due to 30% lower enteric methane production, 13% lower manure nitrous oxide emissions, and 8% lower feed production requirement than when DRC was fed. The carbon-footprints were slightly greater when the diet contained 20% WDGS than when it contained 0% WDGS.

174 A comparison of machine learning algorithms in the classification of beef steers finished in feedlot

Abstract The aim of this project is to compare some of the state-of-the-art machine learning algorithms on the classification of steers finished in feedlots based on performance, carcass and meat quality traits. The precise classification of animals allows for fast, real-time decision making in animal food industry, such as culling or retention of herd animals. Beef production presents high variability in its numerous carcass and beef quality traits. Machine learning algorithms and software provide an opportunity to evaluate the interactions between traits to better classify animals. Four different treatment levels of wet distiller’s grain were applied to 97 Angus-Nellore animals and used as features for the classification problem. The C4.5 decision tree, Naïve Bayes (NB), Random Forest (RF) and Multilayer Perceptron (MLP) Artificial Neural Network algorithms were used to predict and classify the animals based on recorded traits measurements, which include initial and final weights, sheer force and meat color. The top performing classifier was the C4.5 decision tree algorithm with a classification accuracy of 96.90%, while the RF, the MLP and NB classifiers had accuracies of 55.67%, 39.17% and 29.89% respectively. We observed that the final decision tree model constructed with C4.5 selected only the dry matter intake (DMI) feature as a differentiator. When DMI was removed, no other feature or combination of features was sufficiently strong to provide good prediction accuracies for any of the classifiers. We plan to investigate in a follow-up study on a significantly larger sample size, the reasons behind DMI being a more relevant parameter than the other measurements.

Evaluation of methane production manipulated by level of intake in growing cattle and corn oil in finishing cattle.

Growing crossbred steers [n = 80, initial body weight (BW) = 274 kg, SD = 21] were used to evaluate the effect of ad libitum and limit-fed intakes on methane (CH4) production. Two treatments with four pens per treatment (10 steers per pen) were evaluated in a randomized block designed experiment, with BW as a blocking factor. Treatments included feeding the same diet at ad libitum intake or limit fed at 75% of ad libitum intakes. Diet consisted of 45% alfalfa, 30% sorghum silage, 22% modified distillers grains plus solubles, and supplement at 3% on a dry matter (DM) basis. This trial was followed by a finishing trial (n = 80; initial BW = 369 kg; SD = 25) to evaluate the effects of dietary corn oil on CH4 production. Two treatments with four pens per treatment (10 steers per pen) were used in a randomized complete block designed experiment. Cattle were rerandomized and blocked by BW within the previous treatment. Treatments consisted of a control diet (CON) containing 66% corn, 15% wet distillers grains plus solubles, 15% corn silage, and 4% supplement (DM basis). Corn oil treatment (OIL) displaced 3% corn by adding corn oil. Methane was collected in two pen-scale chambers by collecting air samples continuously from pens by rotating every 6 min with an ambient sample taken between pen measurements. Steers fed ad libitum had greater DM intake (DMI) by design and greater average daily gain (ADG; P < 0.01) compared to limit-fed cattle; however, feed efficiency was not different between treatments (P = 0.40). Cattle fed ad libitum produced 156 g/d of CH4, which was greater (P < 0.01) than limit-fed cattle (126 g per steer daily). In the finishing trial, BW, gains, and carcass traits were not impacted by treatment (P ≥ 0.14). Feed efficiency (P = 0.02) improved because intakes decreased (P = 0.02) by feeding OIL compared to CON. Daily CH4 production was less (P = 0.03) for OIL-fed cattle (115 g per steer daily) compared to CON-fed cattle (132 g per steer daily). Methane was reduced (P < 0.01) by 17% for OIL-fed cattle compared to CON-fed cattle when expressed as grams of CH4 per kilogram of ADG. Feeding corn oil at 3% of diet DM reduced enteric CH4 production (grams per day) by 15%, which was only partially explained by a 3% decrease in DMI. Overall, a decrease in CH4 was observed when intake is limited in growing cattle and when corn oil is added in finishing diets.

Associations of mucosal disaccharidase kinetics and expression in the jejunum of steers with divergent average daily gain.

The objective of this study was to quantify the differences in the activity of jejunal maltase and isomaltase between two groups of steers with average dry matter intake (DMI) and differing average daily gain (ADG). DMI and ADG were measured in crossbred steers (n = 69; initial body weight = 456 ± 5.0 kg) consuming a finishing diet containing 67.8% dry-rolled corn, 20.0% wet distillers grains with solubles, 8.0% alfalfa hay, and 4.2% vitamin/mineral supplement on a dry matter basis for 84 d. Jejunal mucosal samples were collected from eight steers with the greatest (high) or least (low) ADG and average DMI (± 0.55 standard deviation). Homogenates of jejunal mucosa were incubated with increasing amounts of maltose and isomaltose to determine the disaccharidase kinetics. Total mucosal protein concentration (mg protein/g tissue; P = 0.45) of the mucosa and small intestinal weights (P = 0.69) did not differ between the groups. Neither the Michaelis-Menten constant (Km) of isomaltase (P = 0.15) nor maltase (P = 0.21) differed between groups. The isomaltase maximum velocity (Vmax) expressed per gram of protein tended to differ (P = 0.10) between groups of steers but did not differ (P = 0.13) when expressed on a tissue basis. Similarly, neither the maltase Vmax expressed per gram of protein (P = 0.31) nor tissue (P = 0.32) differed between groups. While previous studies have indicated that disaccharidase expression is associated with differences in ADG, data presented here indicate that differences in enzyme activity at the end of the finishing period are minimal.

Dry matter intake, performance, carcass traits and expression of genes of muscle protein metabolism in cattle fed increasing levels of de-oiled wet distillers grains

The supply of wet distillers grains (WDG) has been growing in Brazil, with the increase in corn ethanol production. Thus, the aim of this study was to evaluate the effect of de-oiled corn WDG in the diet of feedlot cattle on DMI, performance, carcass traits, meat quality and expression of genes involved in the muscle protein metabolism. One hundred non-castrated F1 Angus-Nellore bulls, aged 20–24 months, with average IBW of 369.58 ± 49.17 kg, were used in a randomized complete block design. The animals were fed diets containing 0, 150, 300 and 450 g/kg de-oiled WDG (40 g/kg ofEE) replacing corn and soybean meal. After 129 days on feed, the animals were slaughtered and LT muscle samples were collected for molecular biology assays. Muscle protein metabolism genes such as eIF4, IGFR1, mTOR, GSK3β and P70S6K were investigated by RTq-PCR. Data were analyzed using polynomial contrasts (linear, quadratic and control versus WDG). The inclusion of by-product improved DMI and FBW (P < 0.05). A tendency (P < 0.10) to a quadratic effect was observed on DMI and FBW, with greater values for animals fed diet with 150 and 300 g/kg of WDG. The animals fed WDG presented greater HCW and CCW (P < 0.05), and there was a quadratic effect (P < 0.05) for the REA, with greater values for the animals fed diet with 300 g/kg of WDG. Moreover, no differences were observed in BFT and carcass pH, and the meat quality traits were similar (P> 0.05) among treatments (SF, CL, ILC, MFI, and WHC). However, the inclusion of WDG led to a reduction in the expression of eIF4, mTOR and IGFR1 genes (P < 0.05). Overall, meat quality traits were not affected by nutritional treatments. Although increased levels of de-oiled WDG influenced DMI, FBW, carcass weights and REA (an indicator of muscle deposition) in response to feeding, it did not produce concerted changes in genes of LT related to muscle protein metabolism.

Correction:Risk factors affecting dairy cattle protective grouping behavior, commonly known as bunching, against Stomoxys calcitrans (L.)on California dairies.

[This corrects the article DOI: 10.1371/journal.pone.0224987.].

Impact of beef consumption on saturated fat intake in the United States adult population: Insights from modeling the influences of bovine genetics and nutrition

We sought to determine the impact of breed and finishing ration that reduces the saturated fat (SFA) content of beef on SFA intake (%E) in adults. Using National Health and Nutrition Examination Surveys (2001–2016), we replaced the current fatty acid profile of beef with that from two breeds (Angus, Wagyu) and three finishing rations (pasture, 15% flaxseed supplementation, 35% wet distiller's grain (WDG) supplementation). Dietary replacement levels in the model were 10%, 25%, 50%, 100%. Overall, men consumed more beef fat than women (12.0 g (11.6–12.4 g, 95%CI) and 6.6 g (6.4–6.9 g, 95%CI), respectively). The contribution of beef fat to SFA intake was 2.1%E (2.1–2.2%E, 95%CI) in men and 1.6%E (1.6–1.7%E, 95%CI) in women. SFA intake decreased with each increased replacement level for all beef types. At 100% replacement, SFA intake decreased 0.5% (Angus), 2.8% (Wagyu), 1.9% (pasture), 4.1% (flaxseed), 2.6% (WDG). Our findings demonstrate that breed and finishing ration that reduces the SFA content of beef can decrease population-level SFA intake.

Factors that affect high voltage atmospheric cold plasma treatment efficacy on wet distillers’ grains: Shelf-life and nutrient composition

The increase in ethanol production continues to drive the availability of distillers' grains, which are used as an animal feed for cattle, swine and poultry. In its wet state this co-product of the ethanol production process must be fed or treated before spoiling and reaching its shelf-life, only 3–5 days after production. Novel treatment technologies, such as high voltage atmospheric cold plasma (HVACP), continue to show promise as a method to increase the shelf-life of many products such as contaminated animal feed. This study investigated the parameters grain depth, amount of sample and exposure time, for effective treatment of distillers’ grains to increase shelf-life using HVACP. This work evaluates the different combinations of treatments to determine, which parameters are critical for reduction in microbial growth and increase shelf-life. The efficacy of the reactive gas species (RGS) produced by HVACP, at 70 kV for up to 360 s, moving through the grain mass of distillers wet grains (DWG) was evaluated by measuring microbial load (log reduction), moisture content and pH after 0, 14 and 28 days of storage at 25 °C at grain depths of 1, 2.5 and 4.5 cm. Results showed a higher log reduction at the 1 cm depth than at 2.5 and 4.5 cm for measurements after the initial treatment. Stored samples continued to show reductions, however the greater depths had higher log reductions than the surface. Nutrient composition and amino acid profiles were also analyzed, showing no significant difference between treated and untreated samples over the storage period.

Impact of Beef Consumption on Saturated Fat Intake in the United States Adult Population: Insights from Modeling the Influences of Bovine Genetics and Nutrition

Abstract Objectives Beef, while a prominent source of high-quality protein in the American diet, is a source of saturated fat. Beef production practices, such as breed selection and nutrition regimens, can influence the nutritional value of meat by reducing the saturated fatty acids (SFA) content. Thus, we sought to determine the extent to which implementing these practices reduces population-level SFA intake to meet the Dietary Guideline for Americans (DGA) recommendation of ≤10% en. Methods Using reported intakes from the National Health and Nutrition Examination Survey 2001–2016, we determined the contribution of food types to total SFA intake. From these data, nutritional modeling methods were used in which the current fatty acid profile of beef was replaced with that from two different breeds (Angus, the predominant breed in the U.S., and Wagyu, a breed with lower SFA content) and three nutrition regimens (pasture-raised, 15% flaxseed supplementation, and 35% wet distiller's grain (WDG) supplementation) to estimate the contribution of each beef type to total SFA intake in the U.S. adult population. Four levels of replacement were compared - 10%, 25%, 50%, 100%. Results Daily per capita SFA intake was 10.9% en (10.8–11.0% en, 95% CI). Beef was the third greatest contributor (15%) to per capita SFA intake, behind grain (29%) and dairy (19%) dishes. In general, men consumed more beef fat than women (12.0 g vs. 6.6 g, respectively). SFA intake, as a percentage of total energy intake (% en), from beef was 2.1% en (2.1–2.2% en, 95% CI) in men and 1.6% en (1.6–1.7% en, 95% CI) in women. For each modeled beef, SFA intake decreased with each increase in replacement level. At 100% replacement, SFA intake was reduced by 0.5% (Angus), 2.8% (Wagyu), 1.9% (pasture-raised), 4.1% (15% flaxseed), and 2.6% (35% WDG). Conclusions Data from this modeling study indicate that decreasing the SFA content of beef through breed selection and nutrition regimens can result in a per capita reduction in SFA intake in the American population. However, modeled SFA consumption remained greater (c. 10.5–10.7% en) than DGA recommended intakes in all age and gender groups. These results demonstrate the importance for Americans to reduce SFA intake from all sources, including beef, to meet daily intake recommendations. Funding Sources United States Department of Agriculture, Agricultural Research Service.

Digestive tract microbiota of beef cattle that differed in feed efficiency.

We hypothesized cattle that differed in BW gain had different digestive tract microbiota. Two experiments were conducted. In both experiments, steers received a diet that consisted of 8.0% chopped alfalfa hay, 20% wet distillers grain with solubles, 67.75% dry-rolled corn, and 4.25% vitamin/mineral mix (including monensin) on a dry matter basis. Steers had ad libitum access to feed and water. In experiment 1, 144 steers (age = 310 ± 1.5 d; BW = 503 ± 37.2 kg) were individually fed for 105 d. Ruminal digesta samples were collected from eight steers with the greatest (1.96 ± 0.02 kg/d) and eight steers with the least ADG (1.57 ± 0.02 kg/d) that were within ±0.32 SD of the mean (10.1 ± 0.05 kg/d) dry matter. In experiment 2, 66 steers (age = 396 ± 1 d; BW = 456 ± 5 kg) were individually fed for 84 d. Rumen, duodenum, jejunum, ileum, cecum, and colon digesta samples were collected from eight steers with the greatest (2.39 ± 0.06 kg/d) and eight steers with the least ADG (1.85 ± 0.06 kg/d) that were within ±0.55 SD of the mean dry matter intake (11.9 ± 0.1 kg/d). In both studies, DNA was isolated and the V1 to V3 regions of the 16S rRNA gene were sequenced. Operational taxonomic units were classified using 0.03 dissimilarity and identified using the Greengenes 16S rRNA gene database. In experiment 1, there were no differences in the Chao1, Shannon, Simpson, and InvSimpson diversity indexes or the permutation multivariate analysis of variance (PERMANOVA; P = 0.57). The hierarchical test returned six clades as being differentially abundant between steer classifications (P < 0.05). In experiment 2, Chao1, Shannon, Simpson, and InvSimpson diversity indexes and PERMANOVA between steer classified as less or greater ADG did not differ (P > 0.05) for the rumen, duodenum, ileum, cecum, and colon. In the jejunum, there tended to be a difference in the Chao1 (P = 0.09) and Simpson diversity (P = 0.09) indexes between steer classifications, but there was no difference in the Shannon (P = 0.14) and InvSimpson (P = 0.14) diversity indexes. Classification groups for the jejunum differed (P = 0.006) in the PERMANOVA. The hierarchical dependence false discovery rate procedure returned 11 clades as being differentially abundant between steer classifications in the jejunum (P < 0.05). The majority of the OTU were in the Families Corynebacteriaceae and Coriobacteriaceae. This study suggests that intestinal differences in the microbiota of ruminants may be associated with animal performance.

Characterization of Zein Extracted from Wet Distillers Grains

Highlights Zein was extracted from wet distillers grains (WDG) with 55%, 70%, and 90% ethanol. Gelation was faster for zein extracted with 70% ethanol than with 55% and 90% ethanol. Alkaline extraction prevented gelation of zein samples. Defatting of WDG increased zein solubility, perhaps by preventing aggregation. Abstract. Coproducts of corn-to-ethanol processing remain potential sources of zein. Attempts to extract zein from dry-grind ethanol coproducts have been limited to distillers dried grains with solubles (DDGS). The aim of this project was to characterize the physicochemical and structural properties of zein extracted from wet distillers grains (WDG) in order to evaluate its quality and functionality. The effect of extraction conditions, including ethanol content of the solvent (55%, 70%, and 90% ethanol), use of NaOH, and defatting of WDG, on zein quality and functionality were investigated. Zein extracted with 70% ethanol showed physicochemical characteristics similar to zein extracted from corn gluten meal. Zein extractions with 55% ethanol were feasible but contained γ-zein and other impurities that affected functionality. Extractions with 90% ethanol contained carotenoids and other lipid materials that may have affected zein behavior. Alkaline extractions resulted in samples with higher protein content but lower solubility. Zein from alkaline extractions resisted particle aggregation and was more stable in solution. Alkaline extractions reduced the α-helix content of the samples and their γ-zein content, reducing viscosity and the tendency to gel. Defatting of WDG improved zein solubility, increased the α-helix content of extracted zein, and prevented aggregation. Extraction and utilization of zein from WDG would contribute to the control of plant operating costs and ease the environmental impact of dry-grind processes. High-quality zein from dry-grind coproducts would enable the development of novel foods and other industrial applications.

Influence of distillers grains with solubles on bull growth and reproductive traits.

This study evaluated the effects of offering growing bulls a diet with 40% modified wet distillers grains plus solubles (MWDGS; dry matter [DM] basis) on growth, composition, hoof scores, and reproductive performance. Simmental × Angus bulls (n = 28) were stratified by body weight (BW; 316 ± 29 kg), sire, and day 0 semen production (Y/N) and assigned into one of six pens. Pens were randomly assigned to one of two dietary treatments (n = 3 pens/treatment): 1) offered free-choice access to a corn-based diet with no MWDGS (CON) or 2) offered free-choice access to a diet with 40% MWDGS (DST; DM basis). Bulls were offered treatments for 140 d and, then, switched to a free-choice, common, low-energy diet for an additional 70 d. Bull BW, body condition score (BCS), hip height (HH), ultrasound (rump fat depth [RF], 12th rib fat thickness [BF], marbling score [MS], and longissimus muscle depth [MD]), hoof evaluations, breeding soundness examination (BSE), and semen evaluations were performed on days 0, 28, 56, 84, 112, 140, 175, and 210. There was a tendency (P < 0.09) for a treatment × time effect for BW. Bulls fed DST tended (P ≤ 0.10) to be heavier on days 28 and 56 than CON bulls. A treatment × time effect was detected (P < 0.01) for RF. Bulls fed DST had greater (P = 0.02) RF on day 84 than CON bulls. Treatment × time and treatment effects were detected (P ≤ 0.05) for BF, in which DST bulls had greater (P ≤ 0.05) BF on days 84, 112, and 175 and tended (P ≤ 0.10) to be greater on days 56 and 210 than CON bulls. A treatment × time effect was detected (P < 0.02) for percentage of major sperm defects. Bulls fed DST had a greater (P < 0.01) percentage of major sperm defects on day 140 than control bulls. There was a tendency (P = 0.09) for a treatment × time effect for percentage of sperm with proximal droplets. Bulls fed DST had a greater (P = 0.01) percentage of sperm with proximal droplets on day 140 than CON bulls. In conclusion, offering growing bulls a diet with 40% MWDGS (DM basis) resulted in heavier BW at days 28 and 56, increased RF at day 84, and increased BF and increases in both major sperm defects and sperm with proximal droplets at day 140. However, after 70 d on the common low-energy diet, there were no carryover effects for any growth, composition, hoof, or reproductive measures except for a tendency for BF.

195 Association of insulin, glucagon, and glucagon-like peptide-1 with production traits of growing and finishing beef heifers fed forage- and concentrate-based rations

Abstract The objective of this study was to determine the association of insulin, glucagon, and glucagon-like peptide (GLP-1) with production traits of growing and finishing beef heifers fed a forage- (FOR) and concentrate-based (CONC) ration. This experiment was conducted over 2 years. Shortly after weaning, heifers (n = 74 and 62, for year 1 and 2, respectively) were placed on a ration containing (DM basis) 69.8% corn silage, 30% alfalfa hay, and 0.2% salt. Feed intake was measured for 84 d using Calan gates and BW were measured at 7-time points to calculate ADG using a quadratic regression of BW on time. Cattle were then transitioned to a concentrate-based finishing ration containing (DM basis) 67.8% dry-rolled corn, 20% wet distillers grains with solubles, 8% alfalfa hay, and 4.2% vitamin/mineral supplement. Blood samples were collected on day 42 of each period. Data were analyzed as a mixed model with fixed effects of sire breed, period, and the random variable of year. Hormone concentration was included as an interaction with period to determine the association of the hormones with production traits. Dry matter intake (DMI), average daily body weight gain (ADG), gain:feed (G:F), and all three hormones were greater in the CONC period (P &amp;lt; 0.01). Insulin was negatively associated with DMI only during the CONC period (P = 0.04) and positively associated with G:F (P = 0.01). GLP-1 was positively associated with CONC DMI (P &amp;lt; 0.01), FOR ADG (P &amp;lt; 0.01), and positively associated with FOR G:F and negatively associated with CONC G:F (P &amp;lt; 0.01). Glucagon was positively associated with residual feed intake (P = 0.04). While these data do not infer causality, they do indicate that more in-depth understanding of the role of gut peptide and insulin signaling in feed efficiency needs to be evaluated.

PSIX-1 Associative effect of wet-distillers’ grains plus solubles and tannin-rich peanut skin supplementation on in vitro rumen fermentation, greenhouse gas emissions, and microbiome changes

Abstract The role of tannin-rich peanut skin (PS) and associative effects of different levels of wet distillers’ grains plus solubles (WDGS) on ruminal fermentation, microbial changes, and mitigation of greenhouse gas (GHG) and other emissions in bovine rumen fluid were investigated. All gases were collected using an Ankom in vitro system for methane (CH4), nitrous oxide (N2O), and hydrogen sulfide (H2S) analyses. Fifteen % ground PS against 0, 10, 20, 30, and 40 % DM of WDGS were used. RT-qPCR were conducted to determine microbial diversity. In the absence of PS, total CH4 and H2S, or CH4 and H2S productions per gram of DM substrate, were linearly increased (P &amp;lt; 0.05) with increasing WDGS. However, in the presence of PS, those trends were reversed and CH4 and H2S productions were decreased (P &amp;lt; 0.05), suggesting that a diet with 15% PS and supplementation of 10 and 20% WDGS were able to reduce CH4 and H2S emissions by 12 and 33%, respectively. In the presence of PS, rumen fermentation rate (as a measured by VFA) and acetate/propionate (A/P) ratio was decreased with increasing WDGS, with PS x WDGS interactions (P &amp;lt; 0.01). In the presence of PS, there was a decreased (P &amp;lt; 0.05) the average population of Bacteroidetes, total methanogens, Methanobrevibacter sp. AbM4, and total protozoa populations at 40% WDGS, with PS x WDGS interactions (P &amp;lt; 0.01). The population of total methanogens (R2 = 0.57; P &amp;lt; 0.01), Firmicutes populations (R2= 0.46: P &amp;lt; 0.05), and F/B ratio (R2 = 0.46; P &amp;lt; 0.03) were strongly correlated with ruminal methane gas production. Therefore, associative effect of tannin-rich PS and WDGS suppressed methanogenesis pathways directly across their antimethanogenic activity and secondarily throughout their modification of protozoa population.

PSXIV-17 Effects of corn bran plus solubles and corn oil on growth performance and carcass traits of finishing bulls

Abstract The objective of this study was to evaluate the growth performance and carcass traits of finishing bulls fed diets containing, on dietary dry matter basis, different levels of corn wet distillers bran plus solubles (WDBS; 0, 15, 30 or 45%) added with or without corn oil (CO; 0 and 3%). A total of 205 Nellore bulls (390 ± 25 kg initial BW) were blocked by initial body weight, distributed in 40 pens and pens within weight block were randomly assigned to treatments in a 2 × 4 factorial arrangement. Diets were isonitrogenous and contained 8.5% sugarcane bagasse and 91.5% concentrate (ground corn, soybean meal, pelleted citrus pulp, urea, mineral). The WDBS (FlexyDDG®) and the corn oil were from SJC Bioenergia (Quirinópolis, Goiás, Brazil). Data were analyzed using the PROC MIXED procedure of SAS. An interaction between CO × WDBS levels was observed for dry matter intake (DMI; P = 0.032). In diets without CO, increasing levels of WDBS linearly (P = 0.004) reduced the DMI, but in diets containing 3% CO, increasing levels of WDBS quadraticaly affected the DMI (P = 0.002). No effects of CO, WDBSF levels or CO × WDBS levels were observed for final body weight, average daily gain, hot carcass weight and dressing percentage. Feed efficiency tended (P = 0.07) to be greater for bulls fed diets containing CO (0.154 vs. 0.144). Increasing levels of WDBS tended (P = 0.09) to increase the feed efficiency. In summary, increasing levels of WDBS in finishing diets linearly (in diets without CO) or quadratically (in diets with CO) reduces the dry matter intake. Adding CO and WDBS tend to increase feed efficiency.

PSXII-29 Utilizing coproducts as an alternative to forage in adapting feedlot cattle to finishing diets affects the ruminal microbiome

Abstract The objective was to determine the interaction of replacing forage with coproducts and the number of step-up diets when adapting feedlot cattle to a finishing diet on the ruminal microbiome. Simmental × Angus and Angus steers (n = 24; 234 ± 38 kg) were blocked by initial body weight (BW) and allotted to 8 pens as a subset of a larger group. Pens were randomly assigned to 1 of 2 dietary treatments: 1) decreasing coproduct (CO; soybean hulls and modified wet distillers grains) inclusion while increasing dry-rolled corn over 36 d or 2) decreasing forage (FO; alfalfa and grass hay) inclusion while increasing dry-rolled corn over 36 d. Pens were fed either 5 (5S) or 2 (2S) step-up diets for each dietary treatment during the 36 d adaptation period in a 2 × 2 factorial design. Steers were fed a common finishing diet for the remainder of the trial (34 d). The ruminal microbiome was evaluated on d 36 and 70. Alpha diversity was greatest (P &amp;lt; 0.01) for FO/2S steers on d 36. A diet × day effect (P = 0.02) was observed for beta diversity as the microbial community was more similar (P &amp;lt; 0.01) between d 36 and 70 for steers fed CO compared with FO. Relative abundance of Bacteroidetes was greater (P = 0.03) for 2S steers compared with 5S steers. Prevotellaceae tended to be greater (P = 0.07) in 2S steers compared with 5S steers. Lactobacillaceae was greater (P &amp;lt; 0.01) on d 36 than d 70. Limited observed day effects for individual taxa suggest the microbiome was well adapted by treatments for the finishing diet on d 36. Greater coproduct inclusion in adaptation diets may alter the ruminal bacterial community to be more similar to the community while feeding high levels of dry-rolled corn.