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A pooled- analysis of UNL feedlot trials examined the impact of starch (corn grain) on cattle performance. Cattle age (calf- fed or yearling) affected DMI, ADG, and F:G, but not marbling score or fat depth. Intake, ADG, F:G, and fat depth were optimized with 50– 70% corn grain in the diet. Marbling was not maximized until the diet contained > 75% corn. Removing either all the corn or all the byproduct from diets did not maximize performance. Including a minimum of 20% byproduct and 20% corn in the diet is biologically advantageous, while the remaining 60% of the diet is flexible based on economics.

It is important to have accurate data on the amounts and nutritive values of residues, especially for grazing situations. Ten plants were harvested for each field replication. Statistical analysis suggests 6 to 10 plants are needed to obtain accurate grain yields and accurate amounts of residue. Further laboratory analysis of the leaves and husks suggests that the energy and protein contents of the residue that is consumed is less than previously reported.

Ten years of performance data from 2005– 2014 were summarized to evaluate the effects of distillers grains plus solubles supplementation or fertilization of smooth bromegrass on performance and economic profitability of yearling steers with corn priced at either $3,4, or 5/bu and DGS priced at either 95, 105, or 115% the price of corn. Steers supplemented with distillers grains on non- fertilized smooth bromegrass had greater ADG (2.37 lb/d) compared with unsupplemented steers (1.69 lb/d). Unsupplemented steers grazing fertilized and nonfertilized pasture had similar gains; however, steers grazing fertilized pasture were more profitable due to savings in land rent. Supplemented steers were more profitable than unsupplemented steers until distillers grains reached 105% the price of $5/bu corn.

Corn plots were serially harvested over 2 years to evaluate changes in nutrient content, digestibility, and yield as plants matured from half- milk line through black layer. In yr 1 (2013), short (102 d) and normal (111 d) season hybrids were grown. Year 2 used 111 d and 112 d hybrids. Silage and grain yield increased until black layer. Silage DM increased with maturity to 42% at black layer. Percent NDF in the stover, NDF- digestibility and overall silage TDN increased quadratically as maturity increased. Th ere is a balance between moisture content, nutrient content, and silage yield, as corn plants mature.

A 190- d calf fed finishing study, utilizing 240 steers, was conducted to determine the effects of supplementing finishing cattle with bypass amino acids (methionine and lysine) on growth performance. Three treatments (control, methionine, methionine and lysine) were evaluated with 8 pens/trt. All cattle were fed a 40% Sweet Bran, 50% high moisture corn basal diet. Supplementing with bypass amino acids did not affect live cattle performance, and only small differences in 12th rib fat and USDA marbling score were observed. Lack of any dramatic changes in performance suggests these calves were not deficient in methionine or lysine.

Four experiments compared wet or dry distillers grains plus solubles (WDGS or DDGS) to corn as energy sources in forage-based diets. In Exp. 1, 66 individually fed steers (268 kg of initial BW) were fed a 60:40 blend of sorghum silage and alfalfa hay and supplemented at 0, 0.33, 0.67, or 1.0% of BW with either WDGS or DDGS. In Exp. 2, 160 steers (286 kg of initial BW) were fed 25% WDGS or 33.6% dry rolled corn (DRC) in 35% sorghum silage and grass hay diets (DM basis). In Exp. 3, 60 individually fed steers (231 kg of initial BW) were fed DRC at 22.0, 41.0, or 60.0%, or WDGS at 15.0, 25.0, or 35.0% of diet DM in 30% sorghum silage and grass hay diets. In Exp. 4, 120 individually fed steers (282 kg of initial BW) were fed DDGS, WDGS (15 or 30% of diet DM), or DRC (22 or 50% of diet DM) in sorghum silage and grass hay diets. In Exp. 1, 3, and 4, increasing DGS inclusion increased ADG (P < 0.01) in forage-based diets. In Exp. 3, cattle consuming WDGS gained more BW than cattle fed DRC (P < 0.01). Using regression analysis, data from Exp. 2, 3, and 4 were pooled to calculate the energy value of WDGS relative to DRC in forage diets. The energy value of WDGS was 137% and 136% of DRC when fed at 15 and 30% of diet DM, respectively.

A finishing study was conducted to evaluate the effects of dietary fat source and presence or absence of monensin on performance, methane (CH4) emissions, and ruminal VFA profile of cattle. No effects on performance or VFA profile were observed. Inclusion of modified distillers grain plus solubles (MDGS) in the diet tended to increase measures of CH4 production when compared to other fat sources (corn oil or tallow), while inclusion of monensin in the finishing diet was not significant for CH4 production.

Profitability through weaning was predicted for conventional and alternative cow-calf production systems using various input price scenarios. At base input price levels, conventional systems were more economical than alternative systems. As pasture price increased, alternativesystems became cost effective. Feeding cows year-round in a confinement setting appeared the least economical; however, an alternative system combining summer drylot feeding with cornstalk grazing is projected to be economically competitive given an increasing abundance of corn residue.

Carcasses of 115 Holstein steers were divided into lean, bone, internal cavity, hide, and fat tissues for analysis of P, Ca, K, Mg, and S retention. Every 28 days, five steers from each of two treatments, fed Zilmax for 20 days prior to harvest or not fed Zilmax, were harvested. There were no differences due to treatment or days on feed when mineral retention was expressed as g/100 g of protein gain. Expressing mineral retention relative to protein gain reduced variation due to rate of gain and animal size.

Steer calves grazing irrigated corn residue were supplemented dried distillers grains plus solubles (DGS) or allowedcontinuous access to a commercial lick tub. Dried DGS was fed at 2.94 lb/steer/day and the lick tubs were consumed at 2.04 lb/steer/day (DM basis). Gain was greater for cattle supplemented with dried DGS (1.36 lb/day) compared to those with access to lick tubs (0.83 lb/day). Supplement efficiency varied between calves receiving dried DGS (46%) and those with continuous access to the lick tub (43%) when expressed on a DM basis. Values for dried DGS supplementation (48%) were not different for supplement efficiencyon an OM basis when compared to cattle on the lick tub treatment (50%). Economic analysis shows that as the price of DGS increases, the difference in profit between supplementation strategiesis reduced.

Irrigated corn residue was sampled across time in order to determine changes in quality and proportion of corn residue as the plant dried and was exposed to effects of weathering. Corn plants from two hybrids were planted on two different planting dates and harvested at periodic intervals from August 2012 to December 2012. Proportions of stem, blade/sheath, husk/shank, and cob made up smaller components of total plant DM as it matured, with the largest relative reduction occurring in the blade/sheath or stem. Hybrid impacted TDN values primarily because the 119 day hybrid was less mature at the early sampling dates.

Mineral retention was measured in 76 beef steers. Cattle were grown at different rates of gain and then finished on a common diet. Calcium and P retention were not affected by treatment and were similar between the growing and finishing periods averaging 4.2 g P and 10.8 g Ca /100 g protein gain across both experiments. As ADG during the growing period was decreased, K, Mg, and S mineral retention during the finishing period were increased. Expressing mineral retention as g/100 g protein gain reducedvariation due to animal size and ADG and suggests that current NRC predictions are accurate.

Cattle diet can impact manure quality and quantity but has minimal impacts on methane production from anaerobic digestion of manure. Quality of manure, measured as OM, does affectmethane production and is largely impacted by the environment cattle are housed in and methods used to collect manure. As the amount of ash contamination of manure was increased, or OM content of the manure was decreased, organic matter degradation and methaneproduction were decreased. With adequate daily cleanout of ash from digesters, open-lot beef cattle manurecan be used for anaerobic digestion.

Three anaerobic digestion trials were conducted to evaluate methane production from feedlot manure. As organic matter content of manure decreased, degradation of manure and methane production also linearly decreased (P ≤ 0.02). Quality, or organic matter content of manure, had a greater impact on anaerobic digestion than diet (with and without distillers grains) fed to cattle. Minerals in manure are concentrated in effluent removed from anaerobic digesters. Knowing mineral retention within cattle allows for more accurate calculation of mineral excretion in manure. Three serial slaughter trials measured mineral retention in growing and finishing cattle. During a growing phase, beef cattle gaining 1.10-1.18 kg/d retained 6.8 g Ca, 3.9 g P, 0.24 g Mg, 1.2 g K, and 0.73 g S/100 g protein gained. Retention of minerals during the growing phase was not affected by diet fed to cattle (P ≥ 0.20). Finishing beef cattle, gaining 1.63-2.02 kg/d retained 7.9-17.3 g Ca, 3.2-6.2 g P, -0.027-0.41 g Mg, 0.48-2.9 g K, and 0.29-1.9 g S/100 g protein gained. Retention of Mg, K, and S during the finishing period was greater (P ≤ 0.02) for cattle grown slowly (< 0.6 kg/d) during the growing phase. Retention of minerals was also measured in Holstein steers serially slaughtered every 28 d after 226 days on a finishing ration. Mineral retention was not affected by addition of zilpaterol hydrochloride in the finishing ration when retention was expressed relative to protein gain (P ≥ 0.14). Retention of Ca, P, Mg, K, and S linearly decreased (P < 0.01) over days on feed when expressed as g/d. Expressing retention relative to protein gain resulted in no differences across days on feed (P ≥ 0.11) averaging 14.4 g Ca, 7.5 g P, 0.45 g Mg, 1.3 g K, and 1.0 g S/100 g protein gained. In all trials, expressing mineral retention relative to protein gain allowed for better comparisons of mineral retention across a range of weights and ADG.

A 2x2 factorial designed experiment was used to study the effects of Micro-Aid and time on OM and N losses from manure, in a simulated feedlot pen setting. Manure was collected from cattle on a common diet, except for the addition of 1 g Micro-Aid /steer daily. Losses of OM were greater at 60 d than 30 d, and greater for control than Micro-Aid. Nitrogen losses at d 30 were similar between treatments but control pans had greater N losses at d 60. Feeding Micro-Aid to cattle may inhibit N volatilization from manure, enhancing the fertilizer value of manure.

A growing study was conducted to evaluate a novel method for measuring methane concentration by feedlot cattle, and to determine the effects of forage quality, inclusion of modified distillers grains plus solubles (MDGS), and presence or absence of monensin on performance, methane concentration, and rumen fermentation characteristics. Performance was improved by use of high-quality forage and MDGS, while response to monensin was variable across basal diet type. Response of methane concentration and volatile fatty acid (VFA) profile due to diet was variable and subject to multiple interactions, reflecting the complexity of the microbial processes involved within the rumen.

Sixty individually fed steers were used to determine the effects of feeding de-oiled modified distillers grains plus solubles (MDGS) on steer performance in an 84-day forage-based growing study. De-oiled MDGS did not significantly alter performance when compared to normal MDGS if fed at the same concentration in growing diets. Inclusion of either de-oiled or normal MDGS at 40% of the diet resulted in improved ending BW, DMI, ADG, and F:G as compared to inclusion of 20% MDGS in the diet.

Steer calves grazing irrigated or non-irrigated corn residue received supplementation of dried or modified distillers grains plus solubles (DGS) at 0.3, 0.7, or 1.1% of BW . Steers were individually supplemented daily through Calan gates. Daily gain improved quadratically with increasing supplementation (1.55 lb/day to 2.12 lb/day) and for calves grazing non-irrigated (2.02 lb/day) compared to irrigated (1.77 lb/day) corn residue. Feeding dry instead of modified DGS did not significantly impact ADG. Supplementing DGS to calves grazing corn residue increased gain during the winter period.

Understanding how management systems impact nutrient cycling is important to pasture sustainability. From 2010 to 2011, we investigated how supplementation of beef cattle (Bos taurus) with corn (Zea mays L.) dried distillers grains plus solubles (DDGS) on unfertilized, rotationally stocked smooth bromegrass (Bromus inermis Leyss.) pasture (SUPP) affected the litter pool, residual herbage mass, litter deposition, and litter quality relative to unsupplemented beef cattle rotationally stocked on unfertilized control (CONT) and N-fertilized (FERT) smooth bromegrass pastures. As hypothesized based on management for greater herbage mass and animal demand during the grazing season, litter deposition was 48% greater in FERT than CONT and SUPP. Management effects, however, depended on year and rotation. Differences in the litter pool, residual herbage mass, and litter deposition typically were greatest before and after the third and fourth rotations, time periods coinciding with peak herbage mass. Meanwhile, deposited litter contained 16.5, 18.1, and 18.9 g N kg–1 and returned 27, 30, and 46 kg N ha–1 through the 158-d grazing season, equivalent to 35, 23, and 34% of total N returning through litter and excreta in CONT, SUPP, and FERT, respectively. Trampling during the 4- to 6-d grazing periods and senescence of herbage contributed to litter deposition. Increase of litter deposition and N return during the grazing season in FERT indicated this system may maintain better soil quality than CONT and SUPP. More research is necessary to examine how changes in litter deposition and N return affect litter decomposition, N losses, and soil organic matter dynamics.

Soil organic matter (SOM) is a key component of pasture production. This is study investigated how management strategies that varied amount and form of N input in a long-term experiment affected concentrations and stocks of total-soil organic C and N, particulate organic carbon (POC), particulate organic nitrogen (PON), root and rhizome mass, C and N contents in topsoil of smooth bromegrass (Bromus inermis Leyss.) pastures with silty clay loam soils in a wet (2010) and dry (2012) year. Management strategies included: (i) unfertilized pasture grazed with unsupplemented beef cattle (CONT); (ii) unfertilized pasture grazed with dried distillers grains plus solubles (DDGS)-supplemented beef cattle (SUPP); and (iii) nitrogen-fertilized pasture grazed with unsupplemented beef cattle (FERT). After 8 yr, management strategies had similar concentrations and stocks of total-soil organic C and N, POC, and PON, and there were no management strategy × year interactions. From 2010 to 2012, total-soil organic C and N, POC, and PON stocks increased as soils dried and soil bulk density increased. The CONT and SUPP management strategies had less root and rhizome mass (concentrations and stocks) and greater soil bulk density than FERT. These belowground responses were consistent with earlier research conducted at the site demonstrating greater herbage accumulation and litter deposition in FERT. Management strategies that vary amount and form of N inputs into pasture appear to have low potential to affect total-soil organic C and N concentrations in the short-term, but long-term effects of less root and rhizome contents remain unknown.

Utilizing manure from cattle fed distillers grains in anaerobic digesters improved methane production and DM degradation of manure compared to manure from cattle fed no distillers grains. Manure from cattle fed in open lot pens had soil contamination which decreased OM content and led to decreased total methane production (L/day), but not when expressed as methane/g OM. If ash buildup is avoided, open lot manure can be used as anaerobic digester feedstock.

A seven-year study from 2005-2011 was conducted to evaluate four grazing management strategies for backgrounding yearling steers on smooth bromegrass pastures. Economic budgets were used to calculate profit differences with current (April 2012) market prices. Overall, cattle receiving supplement had greater net returns, lower cost of gain, and lower breakeven prices. In recent years fertilizer prices have increased at a greater rate than land costs in Nebraska, making it more economical to use a lower stocking rate instead of fertilizing pastures. As land prices increase, the incentive to use either N fertilizer or DDGS supplementation increases.

Long-term responses of pasture plant species to management strategies that vary amount and form of N inputs form a knowledge gap. Our objective was to determine how supplementation of grazing beef cattle (Bos taurus) with corn (Zea mays L.) dried distillers grains plus solubles (DDGS) in unfertilized pasture (SUPP) affects annual herbage accumulation and presence of plant species and functional groups relative to unsupplemented beef cattle on unfertilized (CONT) and N-fertilized (FERT) smooth bromegrass (Bromus inermis Leyss.) pasture. We addressed this objective in the sixth (2010) and seventh (2011) years of a long-term experiment in eastern Nebraska, where N input from DDGS supplementation and urea fertilizer averaged 0, 43, and 90 kg ha–1 yr–1 within CONT, SUPP, and FERT, respectively. For these years, annual herbage accumulation averaged 6.87, 6.80, and 10.58 Mg ha–1 (LSD = 1.49) and 66.5, 66.2, and 76.0% of herbage accumulated by 25 June (LSD = 5.3) in CONT, SUPP, and FERT, respectively. Smooth bromegrass occurred in 99.8% of 0.1-m2 pasture quadrats regardless of treatment. Cessation of N fertilizer input, however, increased presence of annual foxtail (Setaria spp.), annual graminoids, and annuals among quadrats in CONT relative to FERT. Supplementation of DDGS, while shown in previous studies to improve weight gains and N use efficiency in cattle, supplied enough N through excretion to provide an intermediate level of resistance to annual weeds. Nitrogen excreted from cattle supplemented with DDGS, however, did not aff ect herbage accumulation in subsequent years.

The BFNMP$ program was utilized to study effects of dietary nitrogen (N) and phosphorus (P), and N volatilization on economics of manure utilization. Feeding high CP (18.7%) and P (0.5%) diets increased manure net value $6.92/ head compared to manure with a traditional diet (13.3% CP and 0.3% P) being fed. Spreading this manure on a four-year P basis is economical and environmentally friendly.

The goal of limit feeding is to reduce variability in rumen fill at weighing. The amount of rumen fill varies by diet. Cattle included in this study were grazing cornstalks, smooth bromegrass pasture, or in a drylot and fed a forage and modified distillers grains (MDGS) mix. Cattle were limit fed for at least three days and then weighed on two or three consecutive days to obtain a beginning BW. Full weights of individuals were +99 to -86 lb compared to their limit fed weights. The correlation between two-day weights after limit feeding were greater than 0.9, and greater than correlation between full and limit fed weights. We conclude that limit-fed weights are more accurate than full weights.

A meta-analysis of University of Nebraska– Lincoln finishing trials was conducted to evaluate the effect of dietary sulfur on feedlot health. An interactionbetween level of dietary sulfur and forage NDF (P = 0.07) affected the incidence of polioencephalomalacia (PEM) cases. For a given level of dietarysulfur the relative risk for PEM decreasedas forage NDF increased. Rumen degradable sulfur (RDS) was estimated for feedstuffs fed to cattle includedin the analysis. As level of RDS increased in the diet, the incidence of PEM increased (P < 0.01). Rumen degradable sulfur is a better measure of PEM risk because it accounts for the dietarysulfur that contributes to hydrogen sulfide production.

Two treatments (cattle diet) were used in anaerobic digestion of finishing cattle manure. Diet 1 contained 82.5% dry rolled corn (DRC) (CONT) and diet 2 contained 40% wet distillers grains plus solubles (DM basis) replacing DRC (WDGS). Cattle were housed in stanchions for 3 d with complete manure collection in a cement pit. Manure (feces and urine) was sampled and analyzed for minerals, DM and OM. Manure collected was weighed into individual allotments based on DM and frozen. Continuously stirred anaerobic digesters (n = 7, 1 L capacity) were inoculated and maintained for 5 mo before the trial to ensure steady-state. Temperature was maintained at 37°C and pH was maintained between 7.0 and 8.0 via addition of sodium hydroxide. Manure samples collected were thawed and hot water was added to bring total slurry volume to 50 mL. Each day, 50 mL of effluent was removed from each digester and replaced with 50 mL of fresh manure/water slurry (9% DM). Two collection periods were used with 35 d adaptation and 5 d collection, as a switchback. The DM and OM of effluent was measured and DMD and OMD were calculated. Concentration of methane was measured under constant flow of N2 gas. Organic matter in manure averaged 88.3% for CONT and 88.7% for WDGS. Manure DM was 18.3% for CONT and 17.8% for WDGS. CONT and WDGS manure did not differ in total N concentration, 3.95 and 3.79% of DM, respectively (P = 0.54). Sulfur, P2O5, Mg, Zn and Fe were greater in WDGS manure compared with CONT (P < 0.01). Minerals were concentrated approximately 2-fold in effluent compared with manure in both WDGS and CONT. Dry matter degradation was 42.7% for CONT and 44.9% for WDGS (P = 0.05). Organic matter degradation was 51.0% for CONT and 52.9% for WDGS (P = 0.10). Methane production was 0.551 L/d for CONT and 0.634 L/d for WDGS (P = 0.10), equal to 0.116 and 0.137 L/g VS fed (P = 0.05). Feeding distillers grains to cattle does not have large impacts on methane production or degradation of manure in anae

A five-year study from 2005-2009 was conducted to evaluate differences in three grazing management strategies for backgrounding calves on smooth bromegrass pastures. Economic budgets were used to calculate profit differences. Steers supplemented an average of 5.3 lb/day of distillers grains were 90 lb heavier than either of the unsupplemented groups, which resulted in increased revenue of $49.38 for supplemented steers. Land costs were the same per AUM for all treatments but were decreased on a per head basis for pastures with supplemented cattle because cattle were stocked at higher rates than the control. Profit was greatest for the supplemented steers, although the relationship between prices for land, N fertilizer, and DDGS affects the relative profitability of the treatments.

Five years of data were summarized to evaluate cattle and pasture performance when smooth bromegrass pastures were fertilized or cattle were supplemented daily with dried distillers grains with solubles (DDGS) on nonfertilized pastures. Cattle were supplemented at 0.6% of BW for an average of 158 days. Supplemented cattle gained 0.59 lb/day more than unsupplemented cattle. As forage quality declined over the grazing season, ADG also declined but the cattle’s response to DDGS supplementation increased. Each 1 lb of DDGS supplement replaced approximately 1 lb of forage intake. Pastures with supplemented cattle had increased forage production compared to control pastures but less forage production than fertilized pastures.

Two hybrids of grain sorghum, the AWheatland x RTx430 hybrid (CON) and its near isogenic brown midrib counterpart (BMR), were used in a 65-day residue grazing experiment. Grain sorghum was planted in 4 replications for each treatment within the same field, and grazed with 6 steers/replication. Samples of the sorghum residue were collected on days 1, 31, and 60 for neutral detergent fiber (NDF) and in vitro NDF digestibility analysis. Steers grazing the BMR treatment gained 1.55 lb/day while the steers grazing the CON treatment gained 1.32 lb/day (P = 0.14). The BMR and CON were similar in NDF (73.5%), but in vitro NDF digestibility increased by 9.9 percentage units in the leaf portion.

Steers supplemented daily with dried distillers grains with solubles (DDGS) on non-fertilized smooth bromegrass pastures gained 1.9 lb/day compared to 1.46 lb/day for cattle on both fertilized and non-fertilized pastures. The fertilized and supplemented treatments were stocked at equal densities, and the non-fertilized pastures were stocked at 69% the density of the other two treatments. At a lower stocking rate, the non-fertilized pastures showed poorer forage production, but equal cattle performance compared to the fertilized pastures. The supplemented pastures showed slightly decreased forage production compared to the fertilized pastures, but at the same time showed increased cattle performance. Each lb of DDGS replaced about 1 lb of forage. DDGS improved steer and pasture performance when supplemented daily on smooth bromegrass pastures.