Dried Distillers Grains Research Articles

PSI-A-5 Effects of Birth Body Weight Classification on Heifer Growth, Dry Matter Intake, Feed Efficiency, and Grazing Performance

Abstract The objective was to evaluate the effect of birth body weight (BBW) classification on post-weaning growth, dry matter intake (DMI), feed efficiency, and grazing performance of fall-born crossbred heifers. Heifers were classified based on BBW as either light (LtBBW, < -0.5 SD from mean), average (AvgBBW, ± 0.5 SD from mean), or heavy (HvyBBW, > +0.5 SD from mean). Angus and Hereford-sired heifers (n = 153) from commercial Angus dams were utilized in the analysis. Heifers were early weaned at 82 ± 7 days of age. Post-weaning management strategy consisted of calves being kept in partially covered drylot pens and fed a high-energy grain diet (35% dried distillers grains with solubles, 30% whole shelled corn, 30% ground fescue hay, and 5% supplement) in GrowSafe bunks. During the post-weaning evaluation (initiated on day 1), heifer (168 ± 23 kg and 156 ± 7 days of age) DMI was collected for 56 days and body weights (BW) were collected every 14 days. Following the intake evaluation, heifers rotated daily for 166 days though 33 paddocks of 2.4 ± 0.5 hectares each and were weighed every 28 days. Data were analyzed using the MIXED procedure of SAS 9.4. As designed, birth body weight differed (P < 0.01) between classifications (27, 32, and 37 kg for LtBBW, AveBBW, and HvyBBW, respectively). Heifers classified as LtBBW were born earlier (P = 0.02) than AvgBBW and HvyBBW. Heifer BBW classification affected (P < 0.01) weaning weights; heifers classified as LtBBW and AvgBBW had lighter weaning weights than HvyBBW heifers. Birth weight category affected (P < 0.01) BW on days 1, 28, and 56. On day 1, heifers classified as LtBBW were the lightest, AvgBBW were intermediate, and HvyBBW were the heaviest; however, on days 28 and 56, heifers classified as LtBBW were lighter than AvgBBW and HvyBBW. Heifers classified as LtBBW and AvgBBW had less (P < 0.01) DMI and average daily gain (ADG) than HvyBBW during the post-weaning evaluation period. Gain to feed during post-weaning evaluation period was not affected (P = 0.94) by heifer BBW classification. Birth weight category affected (P < 0.01) BW during the grazing season on days 28, 56, 84, 113, 141, 168, 196, and 223. On days 84, 96, and 223, heifers classified as LtBBW were lighter than AvgBBW and HvyBBW; however, on days 113, 141, and 168, LtBBW were lightest, AvgBBW were intermediate, and HvyBBW were the heaviest. During the grazing period, ADG did not differ (P = 0.72) between BBW classifications. In conclusion heavy birth weight heifers had greater post-weaning DMI and ADG when fed a high grain diet; however, grazing ADG did not differ. Heavy birth weight heifers were heavier throughout the duration of the experiment.

251 Effects of Fat Source and Level on Growth Performance and Carcass Characteristics of Commercial Finishing Pigs

Abstract Two experiments evaluated different fat sources and levels on growth performance and carcass characteristics in commercial finishing pigs. In Exp. 1, pigs (n = 2,160 337 × 1050, PIC; initial BW 37.3 ± 0.93 kg) were used. Pens of pigs were blocked by initial BW and randomly assigned to 1 of 4 dietary treatments. Three of the treatments included: 0, 1, and 3% choice white grease fed throughout the trial. The final treatment contained no added fat until pigs were approximately 100 kg, and then the diet containing 3% fat was fed. Experimental diets were fed over 4 phases and were corn-soybean meal-based with 40% dried distillers grains with solubles. There were 27 pigs per pen and 20 replications per treatment. Overall, increasing choice white grease decreased (linear, P = 0.006) ADFI and increased (linear, P = 0.006) G:F without influencing ADG (Table 1). Pigs fed 3% fat only during the late finishing phase (approximately 100 to 129 kg) had similar G:F compared with pigs fed 3% fat for the entire study. Increasing fat tended to increase (linear, P = 0.068) HCW. In Exp. 2, pigs (n = 2,011 PIC 1050 × DNA 600; initially 28.3 ± 0.53 kg) were used. Pens of pigs were blocked by location in the barn and randomly assigned to 1 of 5 dietary treatments arranged in a 2 × 2 + 1 factorial with main effects of fat source (choice white grease or corn oil) and level (1 or 3% of the diet) and a control diet with no added fat. There were 16 replications per treatment with 21 to 27 pigs per pen. Overall, increasing fat, regardless of source, increased (linear, P < 0.001) ADG, decreased (linear, P = 0.013) ADFI, and increased (linear, P < 0.001) G:F. Increasing fat increased (linear, P ≤ 0.016) HCW, carcass yield, and backfat depth (Table 2). There was a fat source × level interaction (P < 0.001) in belly fat iodine value (IV), where IV increased to a greater extent in pigs fed diets containing corn oil with only a small increase in IV in pigs fed diets with choice white grease. In conclusion, the results from these experiments suggest that increasing fat from 0 to 3%, regardless of source, produced variable responses in ADG but consistently improved G:F. Increasing fat increased HCW, carcass yield, and backfat depth, but feeding diets containing corn oil increased belly fat IV to a greater magnitude than choice white grease.

264 Evaluation of Precision Feeding on Production Efficiency Responses in Finishing Beef Cattle

Abstract Charolais-Angus cross steers (n = 128; initial shrunk BW = 505 ± 32.1 kg; n = 16 pens; 8 replicate pens/treatment) were used in a 94-day finishing phase experiment to evaluate animal growth performance outcomes, efficiency measures, and carcass characteristics when varying degrees of ingredient inclusion tolerances were imposed. Treatments included: 1) Normal feeding with 0.454 kg tolerance for all ingredients (FXD) and 2) Variable inclusion strategy where each ingredient was randomly increased or decreased but the targeted as-fed quantity for the daily delivery was met (VAR). All steers were fed twice daily with all bunks managed using a slick bunk approach. Ractopamine HCl was fed (300 mg per head daily) for the final 28 d. Individual BW measures were captured at processing approximately every 35 d. Diets consisted of high-moisture corn (HMC), dry-rolled corn (DRC), dried distillers grains plus solubles (DDGS), liquid supplement (LS), and grass hay (GH) for the first 40 days of the finishing period. Days 41-94 diets consisted of DRC, LS, DDS, GH, and corn silage (CRNSIL). Ingredient inclusions were randomized by assigning independently a random integer to HMC, GH and DDGS with each integer corresponding to the deviation from targeted inclusions; LS inclusion was held constant. As-fed inclusion rates varied from formulated targets by -20, -15, -10, -5, 0, +5, +10, +15, or +20%. DRC or CRNSIL was adjusted so that the targeted as-fed amount of the diet was delivered each day. Data were analyzed using the GLIMMIX procedure of SAS 9.4 (SAS Inst. Inc., Cary, NC) with pen as the experimental unit and block as random effect. VAR steers had increased (P ≤ 0.01) dry matter intake (DMI) and reduced (P ≤ 0.02) kg of gain to kg of feed (G:F). However, no differences (P = 0.75) were detected between treatments for ADG. In addition, net energy for maintenance and gain was decreased (P ≤ 0.01) in VAR. Carcass characteristics for both treatments showed no significance (P ≥ 0.38) in HCW, dressing percentage, rib eye area, rib fat, KPH, yield grade, retail yield, empty body fat, or body weight at 28% estimated EBF. A tendency for increased USDA marbling score (P > 0.08) was noted in VAR. Under the conditions of this experiment, randomly altering ingredient proportions did impact growth performance and efficiency measures. However, despite the difference in growth efficiency carcass characteristics were not impacted.

312 Evaluation of Dietary Roughage Manipulation During the Feeding of Ractopamine Hydrochloride as a Method to Improve Ruminal Health and Control Liver Abscess Severity in Feedlot Steers

Abstract The objective of this study was to determine if additional roughage inclusion to feedlot steer finishing diets during the feeding of ractopamine hydrochloride (RH) is an effective method to improve rumen health and control liver abscess severity. Steers [n = 64; initial shrunk body weight (SBW) = 633 kg ± 35.1 kg] were sourced from an unrelated trial and remained in their previous study pens; pens (n = 8) were assigned to dietary treatment in a completely randomized design. All steers on trial were fed a common 7% [dry matter (DM) basis] roughage equivalent (RE) finishing diet composed of dry-rolled corn, dried distillers grains plus solubles, corn silage, and grass hay for the 58 d preceding study initiation. Steers were fitted with rumination tags to track daily rumination. Dietary treatments were CON: no diet change; and 12R: 5% (DM basis) RE addition to diet via grass hay during the feeding of RH. Steers were fed RH (300 mg/steer/d), finished on treatment diets for 28 d, and harvested at a commercial beef processor. Growth performance, efficiency of dietary net energy (NE) utilization, and continuous carcass data were analyzed with pen as the experimental unit (EU) and fixed effect of treatment. Minutes ruminating was analyzed as an analysis of covariance with individual animal as the EU, fixed effects of treatment, days on feed (DOF) and their interaction, and baseline minutes ruminating as a covariate in the model. Liver abscess prevalence, rumen health, and categorical carcass data were analyzed with the Fisher’s exact test to determine differences between treatments. No difference (P ≥ 0.19) was observed for final SBW, average daily gain, dry matter intake, feed conversion efficiency, dressing percentage, hot carcass weight, calculated yield grade, marbling score, 12th rib fat thickness, calculated empty body fat, observed dietary NE for maintenance and gain, observed-to-expected dietary NE for maintenance and gain, or distribution of liver abscess prevalence, ruminitis score, or USDA yield grade. Ribeye area tended (P = 0.10) to differ between treatments with 12R steers exhibiting a 3.5% larger ribeye. Distribution of USDA quality grade differed (P = 0.003) between treatments with 12R steers having 25% more carcasses grading USDA average choice or better. A treatment × DOF interaction (P = 0.045) was observed for minutes ruminating per day. Daily minutes ruminating was increased (P ≤ 0.05) for 12R on d 1, 2, and 20 and tended to be increased (P ≤ 0.10) for 12R on days 10, 13, 24, and 25. Inclusion of an additional 5% RE to finishing cattle diets during a 28 d RH feeding period can be a management strategy to decrease risk of digestive upsets without sacrificing growth performance or carcass quality.

Effect of dietary supplementation of rice dried distillers grains (rDDGS) on blood profile in Barbari goats

The present study was carried out to determine the effect of feeding different levels of rice dried distiller grains (rDDGS) on haemato-biochemical profile of Barbari goats. Twenty-four Barbari goats of 1-2 years of age were randomly divided into four groups (Control, T1, T2 and T3) having six animals in each group. Barbari goats in control group were fed with basal diet comprising of wheat straw, chaffed green maize fodder and compounded concentrate mixture in a ratio of 20:30:50. The animals in T1, T2 and T3 groups were fed with basal diet supplemented with 10, 20 and 30% of rDDGS on dry matter basis, respectively for the period of 90 days. Results revealed no significant differences on blood profile except WBC (×103/µl), neutrophil (%) and lymphocytes (%) in the groups supplemented with rDDGS. Total protein was found highly significant in T2 group followed by T1 and T3 groups. Total immunoglobulin, catalase, TBARS and ALT in rDDGS supplemented groups were also found significantly different. It was concluded that rDDGS can be incorporated in Barbari goat ration up to level of 20% without having any detrimental effect on health of goats.

Solid-state fermentation of grain sorghum to produce Chinese liquor: Effect of grain properties and fermenting culture

This study evaluated seven U.S. sorghum varieties and nine yeast strains for solid-state fermentation (SSF) to produce Chinese liquor (Xiaoqu baijiu). Among the tested sorghum varieties, Red Waxy had higher single kernel weight, kernel diameter, lower tannin content, and achieved the highest average ethanol concentration (17.7%, v/v). Supplementation of very high gravity fermentation yeast strain HA18 was shown to increase the ethanol concentration consistently regardless of sorghum variety. Strong positive correlations were found between ethanol concentration and crude protein/crude fat contents of distillers dried grains (DDG). Linoleic acid, oleic acid, and palmitic acid were the major fatty acids in sorghum DDG. The major flavor compounds in the fermentation products were ethyl lactate, isobutanol, isoamyl alcohol, phenylethanol, acetic acid, and 2,3-butanediol. The concentrations of these flavor compounds were significantly affected by sorghum grain properties and yeast strain, with more variations of phenylethanol, acetic acid, and 2,3-butanediol.

Isolation and Characterization of the Zearalenone-Degrading Strain, Bacillus spizizenii B73, Inspired by Esterase Activity.

Zearalenone (ZEN) is a widespread mycotoxin found in grain and feed, presenting a serious threat to animal and human health. This study investigated the ability of the novel strain B73, isolated from petroleum-contaminated soil, to detoxify ZEN. B73 was identified as Bacillus spizizenii through physiological and biochemical tests, and further confirmed based on the 16S rRNA gene sequence and the complete genome sequence. B. spizizenii B73 was capable of degrading up to 99.3% of ZEN at a concentration of 10 μg/mL in a minimal medium (pH = 7.0) within 8 h at 37 °C via HPLC-UV. In addition, B. spizizenii B73 was used to treat ZEN-contaminated wheat bran, dried distillers grains (DDGS), and corn meal, whereby the respective degradation rates reached 96.32%, 98.73%, and 80.31% after 36 h of treatment. HPLC-Q-Exactive-MS/MS analysis revealed one of the degradation products to have the formula C17H24O4. B. spizizenii B73 is a novel strain isolated from petroleum-contaminated soil, and the extracellular enzymes secreted by this strain show a remarkable ability to degrade ZEN.

Isolation of porcine reproductive and respiratory syndrome virus from feed ingredients and complete feed, with subsequent RT-qPCR analysis.

We used virus isolation (VI) to determine tissue culture infectivity and reverse-transcription quantitative PCR (RT-qPCR) to determine the stability of porcine reproductive and respiratory syndrome virus 2 (PRRSV) strain P129 in solvent-extracted soybean meal (SBM), dried distillers grains with solubles (DDGS), complete swine feed (FEED), or medium (DMEM) at 4°C, 23°C, or 37°C for up to 3 d. Samples of each treatment were taken at regular intervals and processed. Supernatant was titrated and used to inoculate confluent MARC-145 cells to determine infectivity. RNA was extracted from each supernatant sample and tested by RT-qPCR to determine any change in detectable virus RNA across matrix type, temperature, and time. An interaction (p = 0.028) was observed for matrix × temperature × hour for live virus detected by VI. At 4°C, the concentration of infectious virus was greatest in DMEM, intermediate in SBM, and lowest in DDGS and FEED. DMEM also had the greatest concentration of infectious PRRSV at 23°C over time; a higher infectious virus concentration was maintained in SBM for longer than in DDGS or FEED. At 37°C, a greater concentration of infectious virus was sustained in DMEM than in the feedstuffs, with concentrations decreasing until 48 h post-inoculation. Only matrix type influenced the quantity of viral RNA detected by RT-qPCR (p = 0.032). More viral RNA was detected in the virus control than in DDGS; SBM and FEED were intermediate. By VI, we found that infectious virus could be harbored in SBM, DDGS, and FEED for a short time.

Impact of Partially Substituting Canola Meal with Solvent-Extracted Distillers Grain with Solubles as a Protein Source on Milk Production in a Commercial Holstein Dairy Herd.

The removal of corn oil from dried distillers grains using solvent extraction allows a higher level of inclusion for solvent-extracted dried distillers grains with solubles (SDG) in rations and reduces the risk of milk fat depression in lactating Holstein dairy cows. The objective of this study was to evaluate the impact of substituting 70% of the canola meal (CM) with SDG on milk production and total mixed ration costs. A total of 1408 Holstein cows averaging 91 ± 49 days in milk were randomly enrolled to one of four dietary treatment groups: (1) primiparous control cows (PC) fed 13% CM and 0.21% urea; (2) primiparous SDG cows (PSDG) fed 4.2% CM, 8.8% SDG and 0.42% urea; (3) multiparous control cows (MC) with 13% CM and 0.21% urea; and (4) multiparous SDG cows (MSDG) with 4.1% CM, 8.6% SDG and 0.42% urea. The total mixed rations were formulated to be isonitrogenous. For the income over the feed costs from a control herd, the fed PC and MC's total mixed rations and the fed PSDG and MSDG's total mixed rations were compared. The milk yield, energy-corrected milk, milk fat yield, milk protein yield and milk protein % were lower in the PC cows compared to the PSDG cows. The MSDG cows scored lower in terms of the milk yield, milk protein yield and milk protein % and higher for the 3.5%-fat-corrected milk, milk fat yield and milk fat % compared to the MC cows. The total income, cost of dry matter and income over feed costs per cow/d were higher in the control vs. SDG simulated dairy herds. The control herd had a higher income over feed costs than the SDG herd because the average milk yield per cow/d was higher even though the SDG herd had a lower total mixed ration cost and higher milk fat production.

Mechanical Properties of Solid Biomass as Affected by Moisture Content

The objective of the study was to examine the influence of moisture content on the mechanical properties of solid biomass, which is important for storage and handling. Mechanical properties involving powder flowability were determined with a Jenike shear tester. The materials tested were powdered biomass: sunflower husks, apple pomace, dried distillers grains with solubles (DDGS), and meat and bone meal. In static operations in which powdered biomass is generally under a significant load, such as in silos, moisture deteriorates the mechanical properties of biomass and increases its cohesion. In the case of DDGS, an additional slight decrease in stress was observed for samples with the highest moisture content, which was above 20%. For meat and bone meal and sunflower husks, a lubrication phenomenon was clearly observed, in which biomass samples with increased moisture content manifested better flowability, requiring lower boundary shear stresses than less moist samples. For apple pomace samples, with normal stresses above 50 kPa, the addition of moisture above 10% did not change the values of the observed shear stresses, indicating the stability of their properties. The use of powdered biomass with higher moisture contents, at above 10%, should be avoided, as such material can lead to overhangs in tanks and silos.

Effects of dietary inclusion of dry distillers grains with solubles on performance, carcass characteristics, and nitrogen metabolism in meat sheep: a meta-analysis.

We conducted a meta-analysis in this scientific study to determine the effects of feeding meat sheep dry distillers grains with solubles (DDGS). Thirty-three peer-reviewed articles that met our inclusion requirements and were published between 1997 and 2021 were examined. To calculate the variation in performance, fermentation, carcass features, and nitrogen efficiency between the DDGS and control (no DDGS) treatments, we used 940 sheep weighing an average of 29.1 ± 1.5 kg. We used a hierarchical mixed model to conduct a meta-regression, subset, and dose-response analysis, while taking into consideration categorical variables like breed (pure or cross-breed), and continuous factors, like CP, NDF, and DDGS inclusion rate. Our findings indicate that sheep fed DDGS had higher (p < 0.05) final body weight (51.4 vs. 50.4 kg), neutral detergent fiber digestibility (55.9 vs. 53.8%), and total-tract ether extract digestibility (81.7 vs. 78.7%) than sheep on a control diet. No effects were observed on DMI, CP, and rumen fermentation, but dietary DDGS tended to increase (p = 0.07) HC weight (25.53 vs. 24.6 kg) and meat (redness) color (16.6 vs. 16.3) among treatment comparisons. Dietary DDGS was associated with higher N intake (29.9 vs. 26.8 g/d), fecal N (8.2 vs. 7.8 g/d), and digestibility (71.9 vs. 68.5%). Urinary nitrogen was significantly (p < 0.05) affected linearly by increasing the intake of DDGS in the diet. Based on the dose-response analysis, dietary DDGS inclusion should not exceed 20% to avoid negative effects on performance, nitrogen metabolism, and meat color. Dietary protein from DDGS should not exceed 17% to prevent reduced TVFA concentrations. Breed strongly influenced (p < 0.05) RMD in performance, and inconsistent responses were observed between crossbreed and purebred sheep comparisons. Despite these inconsistencies, no publication bias was observed, but a high variance (Ω2) among comparisons-between-studies was detected. This meta-analysis showed evidence in support of the hypothesis that feeding meat sheep DDGS at a rate of 20% can improve their performance, digestibility, carcass weight, and meat color.

Carbon Sources for Anaerobic Soil Disinfestation in Southern California Strawberry

Anaerobic soil disinfestation (ASD) has been adopted in over 900 ha in California strawberry production as an alternative to chemical fumigation. Rice bran, the predominant carbon source for ASD, has become increasingly expensive. In 2021–22 and the 2022–23 field studies, we evaluated 20–30% lower-priced wheat middlings (Midds) and dried distillers’ grain (DDG) at 21,800 kg ha−1 (in 2021) and 17,000 kg ha−1 (in 2022) as alternative carbon sources to rice bran. The study was placed at Santa Paula, California in September of each season in preparation for strawberry planting in October. Soil and air temperatures were 18–26 °C during that time. After the incorporation of carbon sources into the top 30 cm of bed soil, beds were reshaped, and irrigation drip lines were installed and covered with totally impermeable film (TIF) to prevent gas exchange. Beds were irrigated to saturate the bed soil within 48 h after TIF installation. Anaerobic conditions were measured with soil redox potential (Eh) sensors placed at 15 cm depth in all plots. Both DDG and Midds plots maintained Eh at −180 to 0 mV during the two ASD weeks, while untreated soil was aerobic at 200 to 400 mV. Permeable bags with inocula of Macrophomina phaseolina, a lethal soil-borne pathogen of strawberry, and tubers of a perennial weed Cyperus esculentus were placed 15 cm deep in the soil at ASD initiation and retrieved two weeks later for analyses. Two weeks after that, holes were cut to aerate beds and ‘Victor’ or ‘Fronteras’ bare-root strawberries were transplanted into them. ASD with DDG reduced viable microsclerotia of M. phaseolina by 49% in the first season and 75 to 85% with both carbon sources in the second season. Both ASD treatments reduced tuber germination of C. esculentus 86–90% compared to untreated soil in one of two years. Additionally, Midds and DDG provided greater sufficiency of plant-available nitrogen and phosphorus compared to untreated soil with synthetic pre-plant fertilizer and improved fruit yields by 11–29%. ASD with these carbon sources can suppress soil pathogens and weeds and help sustain organic strawberry production in California.

Study on nutrients, non-volatile compounds, volatile compounds and antioxidant capacity of oyster mushroom cultivated with corn distillers’ grains

Although corn dried distillers' grains (DDG) can be used as a supplement for oyster mushroom cultivation, there are few relevant researches. In this study, oyster mushroom cultivated with different proportions of DDG and corncob mixes was investigated. Based on the cultivation parameters, nutrients, non-volatile compounds, volatile compounds, and in vitro antioxidant capacity of oyster mushrooms were analyzed and compared. The results suggested that the biological efficiency of oyster mushrooms cultivated with 25% and 50% DDG was increased by 33.05% and 26.93%, respectively, and that the protein content was increased by 6.27% and 8.28%, respectively. LC-MS analysis indicated that gallic acid, caffeic acid, erucic acid, linoleic acid and stearic acid were notably increased (p < 0.05). GC-MS analysis revealed that the increment of 1-Octen-3-ol, hexanal, nonanal and azulene offered sweet, grassy, meaty, fatty odor in the oyster mushroom. The DPPH and ABTS radical scavenging rate of oyster mushrooms cultivated on 25% DDG and 50% DDG mixture was higher, and the FRAP of the oyster mushrooms cultivated on 25% DDG mixture was better than the control. Moreover, this study also offers a theoretical basis and application significance for the cultivation of edible fungi with the DDG.

144 Assessment of Backgrounding Management on Growth Performance and Health in Southeastern Beef Calves

Abstract The backgrounding period is a post-weaning management strategy to add weight and build the health status in beef calves. This phase is used to prepare beef calves to enter the next phase of the production supply chain. Weaning and backgrounding management methods can be strategies to reduce calf morbidity and mortality in the feedlot. The objective of this study was to assess beef calf growth performance based on weaning management strategy and subsequent backgrounding using commonly used forage-based diets by Alabama beef producers. A two-year study was conducted using 427 steers (n = 216, year 1, average BW 306kg; n = 213, year 2, average BW 294kg). Steer calves from three Auburn University research farms were randomly assigned based on weaning weights to one of three different weaning method groups: fenceline weaning, nose-flap weaning, or abrupt weaning. After the weaning period calves were brought to a centralized farm and began a 60-d backgrounding period where they were randomized according to previous weaning management, farm of origin and body weight to one of three nutritional management strategies in a 3×3 factorial design: cool-season baleage (oats, ryegrass and crimson clover) and 1% BW dried distillers’ grains (DDGS), bermudagrass hay and 1% BW DDGS, or grazing mixed warm-season annuals and 1% BW DDGS. Body weights were collected on d 0, 30 and 60 of the backgrounding phase. In both years, fenceline weaned calves had the greatest average daily gain (year 1, 0.76 kg/d; year 2, 1.03 kg/d; P = 0.0225) in the first 30 days of the backgrounding period regardless of backgrounding diet type. Calves fed the bermudagrass hay-based diet also had a greater average daily (year 1, 0.78 kg/d; year 2, 1.24 kg/d; P &amp;lt; 0.0001) than both the grazing and baleage diet groups in the first 30 days of backgrounding. From d 30 to 60 of backgrounding in each year, calves on the hay-based diet had the least average daily gain (year 1, 0.19 kg/d; year 2, 0.42 kg/d; P &amp;lt; 0.0001). Steers on both the warm-season annual grazing and cool-season baleage diets supported greater average daily gains (P =0.0041) during the last 30 days of the backgrounding period (0.74 kg/d and 0.75 kg/d, respectively). Steers in year 2 had a greater total gain (year 1, 45.55kg; year 2, 51.56 kg; P = 0.0042) than steers in year 1. However, results in both years indicate that weaning and backgrounding management strategies may influence calf performance during the transition period into the post-weaning phase.

131 Evaluating Supplementation Programs for Growing Calves Grazing Bermudagrass Pastures

Abstract Due to factors such as, high delivery costs, supplement availability, and labor; producers are interested in supplement delivery alternatives. Our objective was to determine gain in response to hand-fed (HF) or self-fed (SF) summer supplementation programs at the University of Arkansas Livestock and Forestry Research Station, on 20, 0.81-ha common bermudagrass pastures at a stocking rate of 5 growing calves per pasture (BW ± SD = 247 ± 24.6) over three years. This was a 2 x 2 + factorial arrangement of treatments, which included: Control (CON) – only free choice mineral; HF 1.13 kg/d by-product-based supplement offered only late summer (LS) or all summer (AS); SF tub supplement (PVM Cattle Tub, Positive Feed Ltd., Sealy, TX) either LS or AS. The HF supplement in year was a 50:50 blend of soybean hulls and corn gluten feed, in year 2 an extruded dried distillers grains cube (MasterHand Milling, Lexington NE) was used for HF, while in year 3 corn gluten feed was the HF supplement. Data were analyzed as a generalized randomized complete block design using the mixed procedure of SAS (SAS Inst. Inc., Cary, NC). Fixed effects in the model included supplementation treatment, year, and year by treatment interaction. Even though different HF supplements were used each year there was no year X treatment interactions (P ≥ 0.10); therefore, results are presented pooled across years. Early summer ADG was greater for HFAS (P &amp;lt; 0.01) than CON and SFAS, while supplemental efficiency (SE, kg added gain/kg supplement) in early summer was less (P = 0.05) SFAS than HFAS. Late summer ADG was greater for HF than SF and CON; while SE did not differ (P = 0.52) among treatments. Total supplement costs, in US dollars per steer for SF, were $67.50 when fed AS and $49.36 when fed in late summer only. Supplement costs for HF were much lower, $33.54 and $15.72/steer for AS and LS, respectively. Cost of added gain for SF was $28.33 and $16.14/kg for SFAS and SFLS, respectively. When providing supplement by HF, cost of added gain was $3.32 and $1.68/kg for HFAS and HFLS, respectively. With these results, we determined the most cost-effective way to add gain with supplement to growing calves grazing bermudagrass pasture is to hand-feed. When calves were HFAS, total supplement costs were higher, but considering the greater ADG, ending bodyweight, and supplemental efficiency ratio, HF supplements should provide a positive net return. Calves on this experiment did not respond as expected to the SF supplement, likely because the bermudagrass pastures in this experiment averaged over3% CP and were in excess of 10% even in the LS sampling periods.

The defoliation dynamics of a stockpiled native grassland pasture follow similar patterns between supplemented and unsupplemented beef calves

AbstractIt is unclear to what extent and on which variables does supplementing beef cattle on native grasslands affect sward structure, specifically on the dynamics of its grazing horizons. Three hypotheses were tested: (i) during a grazing down process under similar forage allowance, supplemented animals take longer to finish each grazing stratum, than their unsupplemented counterparts, (ii) in both cases, the upper stratum will be heavily depleted before the subsequent strata are grazed, (iii) some species and/or forage fractions are consumed faster than others, regardless of the animals being supplemented (corn dried distillers grains with solubles, DDGS, at 0.7% of their body weight, BW, on a dry matter, DM, basis) or not. Three blocks of stockpiled native grasslands were used and split into two treatments plots (n = 6), on which either supplemented (S) or control (C) heifers of 10.6 ± 0.6 months of age and an initial BW of 143 ± 9 kg, were used. A 2.5 × 0.5 m observation grid was installed on the sward, generating 384 observation points on each plot. On these observation plots, sward height (SH) and visually assessed green forage mass percentage (%G) were registered every other day for 12 consecutive days. No differences were found between the horizontal grazing dynamics between supplemented and control animals in terms of how they switched from the upper grazing horizon to the successive ones. In both cases, when the upper grazing horizon was heavily depleted, the subsequent horizon was being depleted by its half. Differences of preference for C3 species over C4 was observed for both treatments, but this effect was more meaningful for control animals. Grazing time never fully compensated for the decline in intake rate during depletion throughout the grazing horizons. Pasture intake declined when the animals transition from grazing the top grazing horizons to the lower horizons, irrespective of the level of supplementation. Managing the sward structure in terms of sward height will be beneficial to maximizing individual animal performance, for both C and S animals. Native grasslands paddocks with a greater C3 gasses predominance will always be preferred to C4 dominated paddocks, regardless of an eventual supplementation practice.

Intake, Growth and Carcass Traits of Steers Offered Grass Silage and Concentrates Based on Contrasting Cereal Grain Types Supplemented with Field Beans, Peas or Maize By-Products.

The study objective was to determine intake and performance of beef cattle individually offered perennial ryegrass-dominant grass silage ad libitum supplemented with 4 kg dry matter daily of, rolled barley or maize meal-based concentrate rations containing supplements of flaked field beans, flaked peas, maize dried distillers grains (MDD) or maize gluten feed (MGF) for 110 days (Experiment 1), rolled barley or rolled oats with or without supplements of flaked field beans or flaked peas for 146 days (Experiment 2), and to quantify the nitrogen balance of diets similar to those offered in Experiment 2 (Experiment 3). The protein supplements were formulated to have similar crude protein concentrations. Cereal type or protein source did not affect intake, growth, feed efficiency and carcass traits in Experiment 1 or 2. Inclusion of a legume protein supplement with barley or oats had no effect on intake or growth performance (Experiment 2), whereas their exclusion decreased nitrogen intake, plasma urea concentrations and urinary and total nitrogen excretion (Experiment 3). The feeding value of barley was similar to oats and maize meal, and flaked beans and peas were similar to MGF and MDD, as supplements to grass silage. Excluding protein ingredients from a cereal-based concentrate did not affect animal performance and reduced nitrogen excretion.

Changes in Fatty Acid Levels during In Vitro Ruminal Fluid Incubation with Different Proportions of Maize Distillers Dried Grains (DDGS)

This study aimed to analyse changes in the profile of long-chain fatty acids in the ruminal fluid of cows during in vitro fermentation, using different proportions of maize DDGS (distillers dried grains with solubles) as a substrate. The serum bottles were filled with 1 g of concentrate feed (C), which consisted of cereal middlings, postextraction rapeseed meal, and soybean meal. Substrates I, II, and III contained the same ingredients as substrate C, but also included DDGS at increasing proportions, while substrate IV contained only DDGS. Ruminal fluid with a buffer was then added to the bottles and incubated for 4, 8, and 24 h. After incubation, the fatty acid profile was analysed using a gas chromatograph. The use of DDGS as a substrate resulted in a decrease in SFA, and an increase in the proportion of UFA, including oleic acid (C18:1n9c) and linoleic acid (C18:2n6c). The fermentation profile with 15% and 20% DDGS in TMR proved to be the most beneficial. These findings suggest that the byproduct of bioethanol production could potentially improve the fatty acid profile in the ruminal fluid, resulting in higher-quality animal products.

Synergistic use of optical and biophysical traits to assess Bromus inermis pasture performance and quality under different management strategies in Eastern Nebraska, U.S.

We investigated the synergic use of optical and biophysical traits to characterize Bromus inermis (smooth bromegrass) pasture lands and assess the combined effects of long-term (15-years) rotational grazing and management strategies of (i) no fertilization (C), (ii) mineral nitrogen (N) fertilization (HF), and (iii) supplemented fertilization through dry distiller grains plus soluble (DDGS; SF)- on forage growth, performance, and quality. We found that fertilization improved pasture’s biomass, specific leaf area, leaf area index (LAI), as well as forage quality. The use of N fertilization did not offer an advantage (e.g., forage quality, yield) over DDGS under both grazed and ungrazed conditions. Optical, proximal sensing techniques allowed the characterization of pasture lands in a non-invasive and time-efficient manner. We tested established vegetation indices (VIs) for their accuracy in identifying and quantifying important physiological and morphological traits. Results showed that the Normalized Difference Vegetation Index (NDVI) and Vogelmann (VOG) were among the best performing indices. Results contribute to our understanding of the impact of long-term fertilization management on Bromus inermis pastures and validate the use of proximal sensing methods. Proximal sensing methods provide direct, non-invasive, and time efficient tool for assessment of the performance and health of vegetation, keys to successful integrative management strategies.

Replacing soybean meal with high-oil pumpkin seed cake in the diet of lactating Holstein dairy cows modulated rumen bacteria and milk fatty acid profile

This research aimed to investigate the effects of replacing soybean meal with high-oil pumpkin seed cake (HOPSC) on ruminal fermentation, lactation performance, milk fatty acid, and ruminal bacterial community in Chinese dairy cows. Six multiparous Chinese Holstein cows at 105.50 ± 5.24 d in milk (mean ± standard deviation) and 36.63 ± 0.74 kg/d of milk yield were randomly allocated, in a 3 × 3 Latin square design, to 3 dietary treatments in which HOPSC replaced soybean meal. Group 1 was the basal diet with no HOPSC (0HOPSC); group 2 was a 50% replacement of soybean meal with HOPSC and dried distillers grains with solubles (DDGS; 50HOPSC), and group 3 was a 100% replacement of soybean meal with HOPSC and DDGS (100HOPSC). We found no difference in the quantity of milk produced or milk composition among the 3 treatment groups. Feed efficiency tended to increase linearly as more HOPSC was consumed. In addition, rumen fermentation was not influenced when soybean meal was replaced with HOPSC and DDGS; the relative abundance of ruminal bacteria at the phylum and genus levels was altered. We also observed that as the level of HOPSC supplementation increased, the relative abundance of Firmicutes and Tenericutes linearly increased, whereas that of Bacteroidetes decreased. However, with increasing HOPSC supplementation, the relative abundance of Ruminococcus decreased linearly at the genus level in the rumen, and the relative abundance of Prevotella showed a linear downward tendency. Changes in dietary composition and rumen bacteria had no significant effect on the fatty acid composition of milk. In conclusion, our results indicated that replacing soybean meal with a combination of HOPSC and DDGS can meet the nutritional needs of high-yielding dairy cows without adversely affecting milk yield and quality; however, the composition of rumen bacteria could be modified. Further study is required to investigate the effects of long-term feeding of HOPSC on rumen fermentation and performance of dairy cows.