Corn Distillers Solubles Research Articles

Corn distillers solubles by two-step proteolytic hydrolysis as a new source of plant-based protein hydrolysates with ACE and DPP4 inhibition activities

Proteins of low-value and underexplored corn distillers solubles (CDS) have not been considerably valorized. Hence, the influence of one-step enzymatic hydrolysis of proteins with alcalase (A), trypsin (T) or flavourzyme (F) and two steps with AT, TA, AF, FA, TF, or FT was assessed to release peptides with angiotensin-I converting enzyme inhibition (ACEi) and dipeptidyl peptidase4 inhibition (DPP4i). The AF hydrolysate was the best sample in terms of yield, protein content, degree of hydrolysis, ACEi (97.68 ± 1.09 %), and DPP4i (51.51 ± 0.28 %). Mass spectrometry of the most active AF hydrolysate (<3 kDa) identified new major peptides like APLA, PLFP, LFLP, LPPYL, PLYPLP, NDWHTGPL, LPPYLPS, GSPFLGQ, SWQQPIVGG. Bioinformatic analysis showed these can inhibit both ACE and DPP4. This is because peptides contain functional groups and adopt conformations significantly binding with other functional groups at enzyme active sites (p < 0.05). This establishes dual bioactivity of peptides, which may have applications in food, feed, and pharmaceutical industries.

Corn distillers solubles as a novel bioresource of bioactive peptides with ACE and DPP IV inhibition activity: characterization, in silico evaluation, and molecular docking.

This study aimed to investigate the biological potential of underutilized and low-value corn distillers solubles, containing a unique unexplored blend of heat-treated corn and yeast proteins, from the bioethanol industries, by bioinformatic and biochemical approaches. Protein hydrolysates were produced by applying four commercially accessible proteases, among which alcalase provided the best results in terms of yield, degree of hydrolysis, molecular weight, number of proteins, bioactive peptides, and deactivation against anti-angiotensin I-converting enzyme (ACE) and anti-dipeptidyl peptidase IV (DPP IV). The optimal conditions to produce anti-ACE and anti-DPP IV peptides were using alcalase for 10.82 h and an enzyme : substrate ratio of 7.90 (%w/w), with inhibition values for ACE and DPP IV of 98.76 ± 1.28% and 34.99 ± 1.44%, respectively. Corn (α-zein) and yeast (glyceraldehyde-3-phosphate dehydrogenase) proteins were mainly suitable, upon enzymolysis, for the release of bioactive peptides. The peptides DPANLPWG, FDFFDNIN, WNGPPGVF, and TPPFHLPPP inhibited ACE more effectively as verified with binding energies of -11.3, -11.6, -10.5, and -11.6 kcal mol-1, respectively, as compared to captopril (-6.38 kcal mol-1). Compared with the binding energy of sitagliptin (-8.6 kcal mol-1), WNGPPGVF (-9.6 kcal mol-1), WPLPPFG (-9.8 kcal mol-1), LPPYLPS (-9.7 kcal mol-1), TPPFHLPPP (-10.1 kcal mol-1), and DPANLPWG peptides (-10.1 kcal mol-1) had greater inhibition potential against DPP IV. The peptides impeded ACE and DPP IV majorly via hydrophobic and hydrogen linkage interactions. The key amino acids TYR523, GLU384, and HIS353 were bound to the catalytic sites of ACE and GLN553, GLU206, PHE364, VAL303, and THR304 were bound to the DPP IV enzyme. The PHs can be used as ingredients in the feed or food industries with possible health advantages.

Evaluation of nitrogenous pyrolysates by Py–GC/MS for impacts of different proteolytic enzymes on corn distillers solubles

The effects of enzymes like alcalase, papain and trypsin generates protein hydrolysates (PH-Ala, PH-Pap and PH-Tryp, respectively) from protein fraction (PF) of corn distillers solubles, were evaluated nitrogenous pyrolysate compounds (PyCs). The differences in absorbance values of amides (I, II, II, A, and B) were distinct to type of enzymatic treatments to PF. The nitrogenous PyCs comprised approximately 12, 21, 16, and 23% from fast pyrolysis of PF, PH-Ala, PH-Pap and PH-Tryp, respectively. Protein hydrolysates from enzyme treatment (PH-Ala, PH-Pap, and PH-Tryp) accumulated N-heterocyclics, amines & amides, and nitriles (10.78 ± 0.72, 8.29 ± 0.30, 9.66 ± 0.83) as the most abundant component and their profiles are further disclosed for these three classes as hexahydro-3-(phenylmethyl) pyrrolo [1,2 a] pyrazine-1,4-dione from PF, PH-Ala, PH-Tryp; bis(2-ethylhexyl) amine, n-butylidenebutylamine, N-butyl-2,2,6,6-tetramethyl-4-piperidinamine, 6-acetamido-n-(5-cyanopentyl) hexanamide from PH-Ala, PH-Pap, PH-Tryp; and phenylacetonitrile & derivatives, phenyl isocyanate from PF, PHs, respectively. The diketopiperazines (DKPs) such as cyclo (Pro-Gly) and cyclo (Phe-Pro) were denoted with area% of 2.43, 7.55, and 4.72 from respective PF, PH-Ala, and PH-Tryp. The out-of-plane and in-plane bending of aromatic CH linkage, NO stretch, NH bend, CO stretch, CN stretch, and saturated aliphatic CH stretch marked nitrogenous PyCs. The findings suggest indicator molecules with monitor of hydrolytic pathways for future value-addition to PF.

35 Effect of feeding 60% dried corn distillers grains plus solubles or the equivalent sulfur on performance, hormone concentrations, and glutathione peroxidase activity in yearling Angus bulls

Abstract The objectives were to investigate the effects of feeding 60% dried corn distillers grains plus solubles (DCD) or equivalent sulfur as calcium sulfate (CaSO4) on performance, hormone concentrations, and glutathione peroxidase (GPx) activity in yearling bulls. Thirty-six half-sibling Angus bulls [256 ± 8 d; initial BW = 320 ± 2 kg] were assigned one of three treatments: 1) corn-based diet containing 60% concentrate (CON; S = 0.18%; n = 12); 2) diet containing 60% DCD as a replacement for corn (DDGS; S = 0.53% DM; n = 12); 3) CON diet + equivalent sulfur of the DDGS diet added as CaSO4 (SULF; S = 0.51%; n = 12). Bulls were fed in Calan gates to target an average daily gain (ADG) of 1.6 kg/d. Data were analyzed as repeated measures using PROC MIXED in SAS. Blood and semen samples were collected on d 0, 56, and 112 then evaluated for concentrations of testosterone, thyroxine, triiodothyronine in serum, and GPx activity in seminal plasma. By design, no differences (P ³ 0.14) were observed among treatments for final BW, ADG or dry matter intake. However, DDGS tended (P = 0.07) to have reduced gain: feed when compared with CON, whereas SULF was intermediate. No differences (P ³ 0.13) were observed among treatments for serum concentrations of testosterone and thyroxine; however, DDGS had reduced (P = 0.009) triiodothyronine concentrations compared with CON and SULF. A treatment ′ d interaction (P = 0.03) was observed for seminal plasma GPx. On d 56, GPx activity was greater (P = 0.03) for DDGS compared with CON, whereas SULF was intermediate, but on d 112, DDGS had greater (P £ 0.02) GPx activity compared with CON and SULF. Therefore, alterations in triiodothyronine concentrations and GPx activity among treatments indicates that DDGS may influence characteristics of semen quality.

PSI-11 Effects of feeding 60% dried corn distillers grains plus solubles or the equivalent sulfur as calcium sulfate on DNA structure and integrity in bull semen

Abstract The objectives of this study were to investigate the effects of feeding 60% dried corn distillers grains plus solubles (DDGS) or the equivalent sulfur as CaSO4 on DNA structure and integrity in frozen/extended bull semen. Thirty-six half-sibling Angus bulls (256 ± 8 d; initial BW = 320 ± 2 kg) were assigned to one of three treatments: 1) corn-based diet containing 60% concentrate (CON; S = 0.18%; n = 12); 2) diet containing 60% DDGS as a replacement for corn (60DDGS; S = 0.55% DM; n = 12); 3) CON diet + equivalent sulfur of 60DDGS added as CaSO4 (SULF; S = 0.54%; n = 12). Bulls were individually fed in Calan gates for 112 days and targeted to gain 1.6 kg/d. Semen was collected via electroejaculation at d 112. Semen samples were extended and frozen. The Guava easyCyte 8HT Flow Cytometer was used to analyze acrosome/cell membrane integrity, mitochondrial energy potential, oxidation status, DNA integrity and the zinc signature assay. Data were analyzed using PROC MIXED in SAS for effects of treatment. For depolarized mitochondria, 60DDGS tended (P = 0.07) to be greater compared with SULF and CON. This suggests that bulls in the 60DDGS treatment may have sperm with lower mitochondrial energy potential compared with SULF and CON bulls. Additionally, for the zinc signature assay, no differences (P ≥ 0.11) were observed for signatures 2 through 4. However, for signature 1, 60DDGS and SULF had decreased (P = 0.03) signature 1 compared with CON suggesting that sperm from bulls in the SULF and 60DDGS treatments may be in advanced stages of sperm capacitation in comparison to CON, potentially limiting the sperm lifespan and ability to bind the sperm oviductal reservoir.

99 Effects of feeding 60% dried corn distillers grains plus solubles or the equivalent sulfur as calcium sulfate on trace mineral concentrations in serum and seminal plasma

Abstract Thirty-six half-sibling yearling Angus bulls [256 ± 8 d; initial BW = 320 ± 2 kg] were assigned one of three diets: 1) 60% concentrate as corn (CON; n = 12); 2) 60% DDGS (60DDGS; n = 12); 3) CON diet + equivalent sulfur of 60DDGS as CaSO4 (SULF; n = 12) to evaluate effects of feeding 60% DDGS or sulfur as CaSO4 on trace mineral (TM) concentrations in serum and seminal plasma. Bulls were fed in Calan gates for 112 days and targeted to gain 1.6 kg/d. Data were analyzed as repeated measures using PROC MIXED in SAS. In serum, treatment × day interactions were observed (P ≤ 0.03) for Cu, Se, and Mo. For Cu, no differences (P &amp;gt; 0.15) were observed at d 0 or 56, but at d 112, 60DDGS was reduced (P &amp;lt; 0.01) compared with SULF and CON. At d 0, no differences (P &amp;gt; 0.09) were observed for Se; however, at d 56 and 112, 60DDGS was greater (P &amp;lt; 0.01) than CON and SULF. For Mo, at d 0, 60DDGS was greater (P = 0.03) than CON, whereas SULF was intermediate, but at d 56 and 112, CON was greater (P &amp;lt; 0.01) than SULF and 60DDGS. In seminal plasma, treatment × day interactions were observed (P ≤ 0.02) for Cu and Mo. For Cu, no differences (P ≥ 0.09) were observed at d 0 or 56, but at d 112, CON and 60DDGS were greater (P &amp;lt; 0.01) compared with SULF. For Mo, at d 0, 60DDGS was greater (P = 0.03) than SULF, whereas CON was intermediate, but on d 56 and 112, CON was greater (P &amp;lt; 0.01) than 60DDGS and SULF. Differences observed for TM may have influenced enzyme activity and semen kinematics which were previously reported.

Application of analytical pyrolysis to gain insights into proteins of condensed corn distillers solubles from selective milling technology

Present study evaluates the analytical pyrolysis to unravel the pyrolysate compounds (PyCs), protein & glycosylation indicators in a protein fraction (PF) from condensed corn distillers solubles (CCDS) of novel selective milling technology. Besides, quadratic and linear correlations using protein content (%) by Dumas method, toluene signature PyC, and elemental nitrogen (%) were developed. Pyrolysis was performed at temperature of 400 °C, where most of the PyCs released from proteins in a lignin-free PF instead of other constituents. The p-cresol and methyl 9,12-octadecadienoate were found with the highest area% of 3.2 and 19.3 in PF and CCDS, respectively. Protein derived PyCs such as nitrogen heterocyclics, amines & amides and nitriles were examined 63.93%, 61.90% and 70% greater in PF than CCDS. Moreover, the indicators of protein were toluene, p-cresol, phenol, phenylacetonitrile, 4-vinylphenol, whereas that of glycosylated protein were methyl mercaptan, furan derivatives, and hexahydro-3-(phenylmethyl) pyrrolo [1, 2 a] pyrazine-1,4-dione. The absence of diketopiperazines provided evidence of crosslinking and aggregation of protein. The values of the protein content obtained from the quadratic model and Dumas method were found to be statistically non-significant (p < 0.05) imply the model validity. The results would aid in bioconversion of CCDS to future value-added products.

Effects of feeding 60% dried corn distillers grains plus solubles or the equivalent sulfur as CaSO4 on DNA structure and integrity in bull semen

Effects of feeding 60% dried corn distillers grains plus solubles or the equivalent sulfur as CaSO4 on DNA structure and integrity in bull semen

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

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

Synergistic effect of surfactants and silica nanoparticles on oil recovery from condensed corn distillers solubles (CCDS)

Most of the oil in condensed corn distillers solubles (CCDS) is in an emulsified form and centrifugation alone is not sufficient to recover the oil in high yield. The synergistic effect between non-ionic surfactants (Tween® 80 and Span® 80) and silica nanoparticles (hydrophilic and hydrophobic) on oil recovery was investigated using 3 batches of commercial CCDS. The use of surfactant mixture with Hydrophilic-Lipophilic-Balance (HLB) value of 9.7 led to the highest oil recovery. Tween® 80/silica and surfactant mixture (HLB 9.7)/silica recovered 5–10% more oil compared with the control groups. However, Span® 80/silica was not effective. Surfactant mixture/silica made the oil recovery by centrifugation more efficient by destabilizing oil-in-water emulsion and washing out free oil droplets. The use of surfactant and silica significantly affected the distribution of different types of oil, as well as centrifugation conditions, heating and shaking. About 20% of total oil remained in the unbroken cells or germ pieces in CCDS, which is unrecoverable without additional treatment.

Effect of dietary fat concentration from condensed corn distillers' solubles, during the growing phase, on beef cattle performance, carcass traits, digestibility, and ruminal metabolism.

The objectives of this study were to determine the effect of fat concentration from corn distillers' solubles (CDS), fed during the growing phase, on DMI, gain, carcass traits, digestibility, ruminal metabolism, and methane emissions of steers. In Exp. 1, 40 steers (age = 136 ± 20 d; BW = 185 ± 11 kg) were randomly allotted to 1 of 5 dietary treatments: 1) a cosrn-based gro\wing diet (CNT), 2) 0% CDS, 3) 10% CDS, 4) 19% CDS, or 5) 27% CDS. Diets 2 through 5 included coproducts (corn gluten feed and soybean hulls) and were formulated to achieve fat concentrations of 3, 5, 7, and 9%, respectively. Diets were fed once daily for 106 d (growing phase). All steers were fed a corn-based diet from d 107 to 196. Contrasts were used to examine 1) the difference between CNT and 10% CDS and 2) linear and quadratic effects of CDS inclusion. During the growing phase, steers fed CNT had increased ( < 0.01) ADG and G:F compared with steers fed 10% CDS. Increasing CDS inclusion increased (linear, ≤ 0.02) ADG and G:F. Overall, steers fed CNT had increased ( < 0.01) ADG compared with steers fed 10% CDS, but increasing CDS inclusion had no effect ( = 0.19) on overall ADG. Overall DMI and G:F were not different ( ≥ 0.16) in any contrast. There was a trend (Linear; = 0.08) for ultrasound marbling at d 196 to increase as CDS inclusion increased; however, there were no effects ( ≥ 0.20) of treatment on carcass marbling or quality grade. In Exp. 2, 5 steers (BW = 335 ± 56 kg) were fed Exp. 1 diets for ad libitum intakes in a 5 × 5 Latin square design. Apparent DM digestibility increased (linear, = 0.02) with increasing dietary CDS inclusion. Steers fed CNT had greater ( = 0.01) DM digestibility than those fed 10% CDS. Fat digestibility increased (linear, < 0.01) in steers with increasing CDS, but NDF and ADF digestibility were not affected ( ≥ 0.17) by treatment. Similarly, ruminal pH and VFA concentrations were not affected ( ≥ 0.13). Also, there was no difference ( ≥ 0.37) in ruminal methane emissions (g/h). In conclusion, feeding corn during the growing phase increased overall ADG compared with 10% CDS coproduct-based diet but did not affect carcass traits or methane production. Increasing dietary fat inclusion from CDS in coproduct-based diets linearly increased DM and fat digestibility and predicted marbling scores via ultrasound but did not affect marbling at slaughter, NDF digestibility, propionate, or methane production.

Effect of corn condensed distillers solubles or corn dried distillers grains during gestation or lactation on cow performance, milk production, and preweaning progeny growth

ABSTRACT Two experiments were conducted to assess the performance of gestating (Exp. 1) or lactating (Exp. 2) beef cows fed increasing concentrations of condensed corn distillers solubles (CDS). In Exp. 1, Angus × Simmental first- (n = 40) and second-parity (n = 8) females were fed 1 of 4 diets starting on d 181 of gestation until 2 wk before calving. In Exp. 2, another set of Angus × Simmental first- (n = 40) and second-parity (n = 8) females were fed diets similar to Exp. 1 from calving until 93 d postpartum. Diets consisted of a corn silage and haylage–based control, a corn stover plus dried distillers grains with solubles diet, and 2 corn stover plus CDS diets fed at a low (LD) or high (HD) dietary inclusion. Inclusion of CDS and distillers grains decreased DMI in both experiments (P

Influence of distillers grains resulting from a cellulosic ethanol process utilizing corn kernel fiber on nutrient digestibility of lambs and steer feedlot performance.

Two experiments evaluated the effects on animal performance of traditional wet distillers grains (T-WDG) compared to cellulosic wet distillers grains (C-WDG) from a new process converting corn kernel fiber into cellulosic ethanol. The resulting coproduct has greater CP and decreased starch and ether extract (EE) concentrations (34.0% CP, 1.6% starch, 7.3% EE) compared to T-WDG (32.5% CP, 5.1% starch, 7.7% EE). In Exp. 1, 10 wethers (34.1 ± 2.35 kg, SD) were used in a replicated 5 × 5 Latin square to evaluate digestibility of DM, fiber, EE, and N. Diets including a corn-based control with 7.5% T-WDG and 7.5% C-WDG (CORN); 30% or 45% inclusion of T-WDG; and 30% or 45% inclusion of C-WDG. Between CORN, 30% T-WDG, 45% T-WDG, or 45% C-WDG, DMI was not different (P ≥ 0.11), but lambs fed 30% C-WDG had decreased (P ≤ 0.05) DMI compared to other diets. Compared to CORN and 30% T-WDG, DM digestibility was lesser ( P< 0.05) for 45% T-WDG or 30% C-WDG, while 45% C-WDG has lesser (P ≤ 0.05) DM digestibility than all other treatments. Digestibility of NDF was not affected by treatment (P= 0.13), and ADF digestibility was not different ( 0.21) between CORN, 30% T-WDG, 30% C-WDG, or 45% C-WDG. However, digestibility of ADF tended to differ (P = 0.06) between 30% T-WDG and 45% C-WDG and was greater (P ≤ 0.05) in lambs fed 45% T-WDG compared to other treatments. In Exp. 2, 168 steers (421 ± 23.9 kg, SD) were used in a randomized complete block design to determine the impact of C-WDG or T-WDG on growth performance and carcass characteristics. Diets included a corn-based control (CON), 30% T-WDG (TRAD), 30% C-WDG (CEL), and 18% C-WDG and 12% condensed corn distillers solubles (CEL+CCDS; = 7 pens of 6 steers/pen). Steers fed TRAD had improved (P ≤ 0.01) ADG, G:F, and HCW compared to steers fed the CON diet. No differences (P ≥ 0.16) in ADG and HCW were noted for steers fed CEL compared to TRAD; however, steers fed CEL had decreased (P = 0.01) G:F due to increased (P = 0.02) DMI compared to TRAD-fed steers. Steers fed CEL or CEL+CCDS did not differ (P = 0.50) in G:F, but CEL+CCDS-fed steers had lesser (P ≤ 0.01) DMI and ADG likely due to greater S content of the CEL+CCDS diet. Overall, while DM digestibility of lambs fed 30% C-WDG was lesser than 30% T-WDG, performance of steers finished on C-WDG was similar to those fed T-WDG. However, WDG from the secondary fermentation appeared to have lesser energy than T-WDG, while maintaining similar cattle performance to corn-fed controls.

Effect of condensed corn distillers solubles concentration on lactation performance of Holstein cows

Forty-eight Holstein cows (32 multiparous and 16 primiparous) in mid to late lactation averaging 219±71 days in milk and 30.5±6.6kg/d of 3.5% fat-corrected milk were used in a 56-d completely randomized design experiment to evaluate condensed corn distillers solubles (CCDS) inclusion in high-fiber total mixed rations (TMR). Inclusion rates evaluated were 0, 6.6, 13.2, and 19.8% CCDS as a percentage of dry matter (DM). Distiller solubles substituted for soybean meal, corn grain, and whole cottonseed such that diets were similar in protein (16.6%) and fat (4.50%). Water was added to 0, 6.6, and 13.2% CCDS treatments so that final TMR DM concentrations (47.8%) were similar across diets. The forage portion of the diet was kept constant at 19.6% annual ryegrass hay and 26.0% sorghum baleage. Diet in vitro true digestibility tended to increase as CCDS addition increased, but neutral detergent fiber digestibility trended lower in CCDS diets. Percent P (0.39, 0.55, 0.69, and 0.73%) and S (0.32, 0.35, 0.39, and 0.42%) in TMR increased as CCDS concentration increased. Milk yield (23.5, 24.7, 25.5, and 24.8kg/d of 3.5% fat-corrected milk) was similar for control and CCDS diets. Milk fat (3.88, 3.73, 3.78, and 3.68%), protein (3.28, 3.27, 3.31, and 3.31%), and lactose (4.61, 4.66, 4.69, and 4.77) percentages were similar across diets. Milk urea nitrogen (16.60, 15.58, 15.43, and 14.75mg/dL) declined with increasing CCDS addition. Animal activity, body weight, body condition scores, and locomotion scores were not influenced by CCDS. Day 28 poststudy locomotion scores were similar across diets. Ruminal acetate concentrations did not differ among diets, but propionate and butyrate concentrations were elevated in rumen fluid of cows receiving 19.6% CCDS. Although rumen fluid pH values were similar (6.5, 6.4, 6.3, and 6.2), the two highest CCDS diets exhibited depressed acetate:propionate ratios relative to controls. The results from this study indicate that CCDS may be included in high-fiber TMR for lactating dairy cows at up to nearly 20% of diet DM; however, caution is recommended because high CCDS P concentrations may create Ca:P imbalances and excess P may be introduced into the environment.

Increasing dietary neutral detergent fiber concentration decreases ruminal hydrogen sulfide concentrations in steers fed high-sulfur diets based on ethanol coproducts.

Cattle feedlot diets commonly contain ethanol coproducts that are high in S. This dietary S is reduced in the rumen by sulfate reducing bacteria, resulting in an accumulation of hydrogen sulfide (H2S), increasing the risk for S toxicity. A negative correlation between H2S and ruminal pH has been observed previously. The objective of this study was to determine the effect of varying dietary NDF from chopped bromegrass hay (66% NDF) on performance, ruminal pH, and ruminal H2S gas concentration of steers fed a high-S finishing diet. One hundred fifty crossbred steers (359 ± 51 kg BW) were blocked by BW into pens of 5 steers and randomly assigned within block to 1 of 5 treatments (n = 6 pens per treatment) and fed for 84 d. Dietary treatments included 3.5, 5.7, 7.9, 10.1, or 11.4% roughage NDF (rNDF) from bromegrass hay and contained 0.46% dietary S from a combination of dried distillers grains with solubles and condensed corn distillers solubles. In all diets, hay was added at the expense of dry-rolled corn. Effective NDF increased linearly (P < 0.01) with increased inclusion of rNDF. Final BW was not affected by rNDF (P ≥ 0.12). The addition of roughage did not affect ADG (P ≥ 0.13) or gain efficiency (P ≥ 0.12). Dry matter intake increased linearly (P < 0.01) as rNDF concentration increased. There was a treatment × month interaction for S intake (P < 0.01), explained by steers fed 3.5 or 11.4% rNDF increasing S intake each month whereas the middle rNDF inclusions had similar S intake between months 1 and 2 and increased in month 3. Ruminal H2S concentrations and ruminal fluid pH were measured at 6 h postfeeding on d 7, 14, 21, 29, and 84. Ruminal pH increased linearly (P < 0.01; 5.48, 5.61, 5.71, 5.74, and 5.80 ± 0.041 for 3.5, 5.7, 7.9, 10.1, and 11.4% rNDF, respectively) and ruminal H2S concentrations decreased linearly (P < 0.01; 1.00, 0.86, 0.76, 0.70, and 0.62 ± 0.037 g/m(3) for 3.5, 5.7, 7.9, 10.1, and 11.4% rNDF, respectively) as rNDF inclusion increased. Using mixed model regression analysis, ruminal pH had a strong negative relationship with ruminal H2S concentrations (β = -0.63; P < 0.01). Under conditions of this study, increasing roughage did not affect cattle gains but helped maintain greater ruminal pH and decreased H2S concentration, suggesting that this dietary strategy may lessen the risk of S toxicity in feedlot cattle.

Effects of dietary sulfur source on rumen pH and hydrogen sulfide gas concentration

A variety of sources of S have been utilized to study S toxicity in cattle; however, it is unknown if these S sources have similar potential to produce ruminal hydrogen sulfide (H2S). The objective of this study was to evaluate the effects of different sources of dietary S commonly used in ruminant S toxicity research on ruminal pH and gas-cap H2S. Five cannulated steers were used in a 5×5 Latin square and fed 1 of 5 diets containing 0.49% S once daily at 1.3% of body weight (DM basis). Dietary S sources included ethanol co-products: dried distillers grains plus solubles (DDGS), condensed corn distillers solubles (CCDS), or inorganic sources: sulfuric acid (SA), sodium sulfate (SS), and calcium sulfate (CS). All diets contained 45% corn and 10% grass hay (DM basis). In the DDGS treatment, DDGS was included at 42% diet DM and contributed 0.40% S. In the non-DDGS treatments, DDGS was included at 21% diet DM and contributed 0.19% S to these diets. In the CCDS treatment, CCDS was included at 7% diet DM and contributed 0.19% S to the diet. For the inorganic treatments (SA, SS and CS) S sources contributed 0.17% S to the diet. In the non-DDGS diets, soyhulls were included to make up the balance of diet DM (15% diet DM for CCDS diet and 21% diet DM for the inorganic S source diets). Sampling of ruminal pH and H2S gas concentration occurred at 6h post-feeding. Diet pH (P<0.01; SEM±0.032) differed due to S source, with SA (3.93) having the lowest pH (P<0.01) whereas SS (4.79) and CS (4.79) were greatest (P<0.01), but did not differ (P=0.97). The co-product diets were intermediate, with DDGS (4.08) having a lower (P<0.01) pH than CCDS (4.18). However, ruminal pH at 6h post-feeding (SEM±0.076) was least (P<0.01) for CS (5.03), followed by SA (5.28) which was lesser (P≤0.05) than DDGS (5.40), SS (5.43), and CCDS (5.50) which did not differ (P≥0.09). There was no difference in S intake (P=0.31) or ruminal H2S concentration (P=0.62) among treatments. Even though dietary pH varied among treatments ruminal pH differences were minimal and no differences in ruminal H2S were observed, suggesting that results of experiments utilizing these different S sources to research S toxicity may be comparable.

Performance characteristics of beef cows program fed by-products from corn ethanol production

The objective of this experiment was to evaluate the efficacy of programfed, corn-silage-based diets containing reduced-fat, modified wet corn distillers grains (RFDGS); high-fat, modified wet corn distillers grains (HFDGS); or highfat, condensed corn distillers solubles (HFCDS) containing 8.01, 10.53, and 10.99% ether extract (crude fat), respectively, on beef cow and calf performance. Angus × Simmental crossbred cows (n = 128) were program fed 1 of 4 dietary treatments for 206 d beginning in the third trimester through calf weaning. Cows were blocked by parity (first parity and 2 or more parities) and stratified within parity by BW subject to variation in BCS to 16 pens. Each block was equally represented within treatment. Control cows were fed diets based on corn silage, shelled corn, and soybean meal to provide 12.0% CP (T1). In treatment diets, corn silage and either RFDGS (T2) or HFDGS (T3) replaced shelled corn and soybean meal to provide 12.0% CP. High-fat, condensed distillers solubles (T4) replaced shelled corn and a portion of soybean meal to provide 12.0% CP. Cow DMI per day was lower (P = 0.01) for T3 comparing 10.13 ± 1.12, 9.88 ± 1.02, 8.07 ± 0.88, and 10.08 ± 1.20 kg for T1, T2, T3, and T4, respectively. Crude fat composition of the diets was different (P = 0.001), where T1 T2 and T3, T1 = T4, and T1 = T2 = T3. Milk urea nitrogen differed between treatments (P = 0.02), where T1 > T2 and T3, T4 = T1, and T4 = T2 = T3. No differences (P > 0.05) between treatments were observed for calf BW and cow BW and BCS at the end of the feeding period. Calf birth weight tended (P = 0.10) to be lower for T3 compared with T1, T2, and T4. In corn silage– based diets when beef cows are program fed to maintain similar BCS, HFDGS, RFDGS, and HFCDS can replace shelled corn and soybean meal, with similar performance.

Influence of feeding increasing levels of dry corn distillers grains plus solubles in whole corn grain-based finishing diets on total tract digestion, nutrient balance, and excretion in beef steers1,2

Four crossbred steers (average BW = 478 ± 33 kg) were used in a 4 × 4 Latin square design to determine the effects of dietary concentration of dry corn distillers grains plus solubles (DDGS) in whole corn-based finishing diets on total tract digestion and nutrient balance and excretion. The DDGS were fed at 0% (control), 16.7%, 33.3%, and 50% of dietary DM. All diets contained 10% (DM basis) alfalfa/grass haylage and were formulated to meet or exceed the estimated requirements for CP. Steers were fed the experimental diets ad libitum for a 14-d adaptation period followed by a 5-d period for fecal and urine collection. Increasing concentration of DDGS in diets from 0 to 50% of DM linearly decreased (P < 0.05) total tract DM and starch digestibility (from 77.8 to 72.9%, and 89.2 to 81.5%, respectively). Daily N and P intakes linearly increased (P = 0.06 and P = 0.01, respectively) with increasing DDGS concentration. Fecal and urinary N, P, S, Mg, and K excretion linearly increased (P < 0.05) with increasing DDGS concentration; however, Se and Na excretion did not differ (P > 0.38) among treatments. Retention (g/d; intake minus urinary and fecal excretion) of N did not differ (P > 0.16) among treatments. Retention of P tended (P = 0.07) to linearly increase and retention of S (g/d) linearly increased (P = 0.004), with increasing DDGS concentration. There were no effects (P > 0.16) of dietary treatment on digestion and retention of Se, Mg, K, and Na. Plasma P and S concentrations increased (P = 0.03 and 0.01, respectively) with increasing DDGS concentration. These data indicate that feeding DDGS up to 50% of dietary DM in whole corn grain-based finishing diets does not have a negative effect on nutrient retention but decreases digestibility. Total excretion of N, P, Ca, Mg, S, and K increased as DDGS concentration increased.

Determining the influence of dietary roughage concentration and source on ruminal parameters related to sulfur toxicity

Cattle feedlot diets often include ethanol coproducts that provide excess dietary sulfate, which is reduced to sulfide by ruminal bacteria and can be converted to hydrogen sulfide, which has been correlated to S toxicity. The objective of this study was to determine the impact of feeding varying concentrations of NDF from chopped cornstalks (CS) or chopped bromegrass hay (BH) on ruminal pH, ruminal H2S concentration, and DMI of steers fed a high-S finishing diet. Five ruminally fistulated steers (595 ± 87 kg BW) were used in a 6 × 6 Latin square with 14-d periods and fed diets containing 0.45% S from a mixture of dried distillers grains and condensed corn distillers solubles. The study was a 2 × 3 factorial arrangement of treatments with 2 roughage sources--CS or BH--and 3 concentrations of added roughage NDF (rNDF)--4, 7, or 10%. Steers had individual ad libitum access to feed and adapted to each diet for the first 7 d of each period. Effective NDF linearly increased (P < 0.01) as rNDF increased and did not differ between sources (P = 0.44). There was no effect of concentration or source of rNDF on DMI (P ≥ 0.69). Steer behavior was observed on d 13 of each period for 3 h postfeeding. Source of rNDF did not affect time at bunk, DMI during observation, or rate of DMI (P ≥ 0.42). Time at bunk linearly increased as rNDF increased (P = 0.01), while rate of DMI linearly decreased (P = 0.02). Area under the curve for ruminal pH of 5.4, 5.6, and 5.8, calculated using data from d 8 to 14 via an indwelling ruminal bolus, were linearly decreased (P ≤ 0.03) as rNDF increased. Manual ruminal pH taken 6 h postfeeding on d 14 of each period did not differ by source (P = 0.12) but linearly increased (P < 0.01) as rNDF increased. Ruminal H2S concentrations measured 6 h postfeeding on d 14 of each period did not differ by source (P = 0.47) but linearly decreased (P < 0.01) as rNDF increased (0.62, 0.35, 0.31 g/m(3) for 4, 7, and 10% rNDF, respectively). A segmented linear model was found to best fit the ruminal pH and H2S relationship data, suggesting that at or below a pH of 5.6 ± 0.08 with 95% confidence intervals of 5.4 and 5.8, pH is a strong predictor of H2S (P ≤ 0.05), while above this pH range H2S concentrations are not well correlated with ruminal pH (P > 0.50). In conclusion, adding at least 7% NDF from CS or BH to high-S feedlot cattle diets will increase ruminal pH and decrease H2S concentrations, thus decreasing potential for S toxicity.

Limit feeding nonlactating, nonpregnant beef cows with bunkered wet distillers grains plus solubles or distillers solubles

ABSTRACT Nonlactating, nonpregnant beef cows (593 ± 10.0 kg) were used in a completely randomized design to evaluate the performance of limit-fed diets containing bunkered wet distillers grains plus solubles (WDGS; n = 24) or bunkered condensed corn distillers solubles (DS; n = 22) compared with a control diet offered ad libitum (CON; n = 24). Cows were stratified by age and BW and randomly assigned to pens (3 pens/treatment, 7 or 8 cows per pen). The WDGS and DS were mixed and stored with 30% and 59% ground cornstalks (DM basis), respectively, for 30 d before feeding. Diets were fed for 76 d and formulated to maintain BW. Both WDGS and DS diets contained 41% by-product and 59% cornstalks at time of feeding, with DMI limited to 7.7 kg/d. The CON diet consisted of 43% bromegrass hay, 34% cornstalks, and 23% alfalfa haylage and was fed ad libitum (DMI = 10.4 kg/d). The WDGS diet was 4.1% fat and 0.24% sulfur. The DS diet was 5.5% fat and 0.37% sulfur on a DM basis. Initial BW and BCS among treatments were similar. Final BW was greater (P