Wet distiller’s grains with solubles are the most common feedstuff generated by the ethanol industry, and this feedstuff has been utilized by the feedlot industry. Exploration of the effect of dietary distiller’s inclusion on the form and quantity of protein or nitrogen (N) has received little attention. Assessment of degradable N needs in diets containing wet distiller’s grains with solubles (WDGS) is needed to aid the cattle feeding industry in managing feed costs and potential environmental issues. In Exp. 1, 525 yearling steers (initial weight = 373 ±13 kg) received treatments in a 2 × 3 1 factorial. Factors included corn WDGS (15 or 30 percent of DM) and non-protein N (NPN; 0, 1.5, or 3.0 percent of DM) from urea. The control diet without corn WDGS contained 3.0 percent NPN (1.06 percent urea) and cottonseed meal. Overall gain efficiency among steers fed 15 percent corn WDGS was greatest for 1.5 percent NPN and least for 0 percent NPN (P = 0.07, quadratic), whereas gain efficiency decreased linearly (P < 0.09) as NPN increased in the 30 percent WDGS. Dressing percent was greater (P < 0.01) for the control diet than for 15 percent or 30 percent WDGS. In Exp. 2, 296 steer calves (initial BW = 344 ± 12 kg) were adapted to a common finishing diet, blocked by BW, and assigned to treatments. Experimental diets included a control diet without WDGS (contained 3 percent NPN from urea, and cottonseed meal) and 15 percent WDGS with either 1.50, 2.25, or 3.00 percent NPN (0.52, 0.78, and 1.04 percent urea, respectively, on a DM basis). Overall gain efficiency on either a live or adjusted basis was not different among treatments (P > 0.15). Dietary NPN concentration did not influence growth performance (P > 0.21). Results suggest that optimum performance for cattle fed 15 percent WDGS occurred when the diet contained between 1.5 percent and 2.25 percent NPN. However, removing all supplemental NPN was necessary to support optimum performance in diets containing 30 percent WCDG.

Master of Science / Department of Animal Sciences and Industry / Robert Goodband / Five experiments were conducted to determine the effects of sorghum dried distiller’s grains with solubles (DDGS) on nursery pig performance, finishing pig performance and meat quality, and lactating sow and litter performance. Experiment 1 established a nutrient database and evaluated the quality and consistency of five ethanol plants in the Western Plains region. Each sample was analyzed for AA, DM, CP, crude fiber, crude fat, ash, NDF, ADF, Ca, P, trace minerals, GE, and starch. In addition, DE, ME, and NE were calculated. Experiments 2 and 3 evaluated the effects of sorghum DDGS on nursery pig performance. In Exp. 2, pigs fed sorghum- or corn-based diets performed similarly; however, as sorghum DDGS increased ADG decreased (linear, P < 0.01). A DDGS×grain source interaction (quadratic, P = 0.03) was observed for G:F. In corn-based diets, G:F was identical for pigs fed 0 to 30% DDGS, but worsened in pigs fed 45% DDGS. In sorghum-based diets, G:F was best for those fed 0% DDGS, but worsened at higher levels. In Exp. 3, pigs fed corn- or sorghum-based diets performed similarly; however, pigs fed DDGS gained less (P < 0.03) than those fed basal diets. Experiment 4 evaluated the effects of sorghum DDGS in sorghum- or corn-based diets on finishing pig growth performance, carcass characteristics, and fat quality. Increasing sorghum DDGS reduced (linear; P < 0.01) ADG and increased (linear; P < 0.01) backfat IV. Pigs fed the sorghum-based diet with 30% sorghum DDGS had decreased backfat IV (P < 0.01) than those fed the sorghum-based diet with corn DDGS. Experiment 5 evaluated the effects of sorghum DDGS on lactating sow and litter performance. Overall, ADFI increased in corn-based diets when DDGS were added, but decreased in sorghum-based diets resulting in a tendency (P < 0.08) for a DDGS × grain source interaction. Pig weaning weights were lower (P < 0.06) for sows fed diets containing DDGS compared with those fed the basal diets. Adding sorghum DDGS reduced pig performance, and sow lactation performance; therefore, its inclusion in swine diets needs to be evaluated on an income over feed cost basis.

The objective of this study was to examine the effects of 70% (DM) inclusion of dried distillers' grain with solubles (DDGS) on performance and meat quality. Ninety-six Angus steers (276 kg ± 7.5 kg initial BW) were used in an completely randomized design with incomplete replication. Steers were stratified by BW to pens and pens were randomly assigned to one of 6 treatments: 1) 80% corn; 5% soybean meal; 15% corn silage, fed as a negative control (CON); 2) 40% DDGS: 45% corn: 15% corn silage, fed as a positive control (PCON); 3) steers received PCON (0-84d) then switched to a diet of 70% DDGS: 15% corn: 15% corn silage until finished (40/70); 4) steers started on 70% DDGS: 15% corn: 15% corn silage (0-84d) then switched to PCON until finished (70/40); 5) CON + soybean meal, isonitrogenous to PCON (N40); 6) CON + corn oil, isocaloric to PCON (E40). Steers were fed respective treatments until 80% of them reached low choice or higher by visual appraisal, providing their genetics allowed (168 and 213 days). Dry matter intake, DMI, (P &ge 0.82) was not affected by treatment, isocaloric, or isonitrogenous diets. End weight was greater (P = 0.04) for PCON steers compared to N40 steers. However, no treatment effect (P &ge 0.15) on G:F. Dietary treatment did not affect HCW, quality grade, %KPH, or liver score (P &ge 0.12). Yield grade was not affected (P = 0.12) by treatment but tended to be lower (P = 0.06) for N40 steers compared to PCON steers. However, N40 steers had a larger (P = 0.04) ribeye area and greater rib fat (P = 0.05) when compared to PCON and ribeye tended (P = 0.06) to be smaller in 70/40 and E40 steers compared to all other treatments. Minotola color, % cook loss, shear force, total SFA, total PUFA, total MUFA or lipogenic activity were not affected (P &ge 0.08) by treatment. The data of this study suggests that it is possible to feed 70% DDGS in feedlot rations with little to no adverse effects on growth performance or meat quality.

Master of Science / Department of Animal Sciences and Industry / James S. Drouillard / A series of five trials were conducted to evaluate grain processing, distiller's grains inclusion in finishing diets, interactions between distiller's grains and dry-rolled corn (DRC) or steam-flaked corn (SFC), efficacy of removing roughage in the presence of distiller's grains and the digestibility of distiller's grains in steam-flaked and dry-rolled corn diets. The first trial was designed to determine the optimum flake density of SFC in beef finishing diets. Diets consisted of corn flaked to densities of 360, 411, or 462 g/L. Observed improvements in mill production would support increasing flake density; however numerical decreases in animal performance offset economic benefits of increased productivity. The second trial was conducted to evaluate optimum levels of sorghum wet distiller's grains in finishing diets. Crossbred yearling steers were fed diets containing DRC or SFC and levels of distiller's grains were 0, 10, 20, or 30% of diet dry matter. Distiller's grains can effectively replaced a portion of the corn in finishing diets, but their nutritional value was greater in DRC diets than in SFC diets. In trial 3, crossbred heifers were fed diets containing SFC with 0% DDG and 15% corn silage (CS), 25% DDG and 15% CS, or 25% DDG and 5% CS. In trial 4, crossbreed heifers were fed diets similar containing DRC or SFC with 0% DDG and 15% CS, 25% DDG and 15% CS, or 25% DDG and 5% CS. Results indicate that roughage levels can be reduced in feedlot diets containing DDG with no adverse effects on performance or carcass quality. The fifth trial was a metabolism study conducted to evaluate the digestibility of DDG in beef cattle. Treatments consisted of DRC with 0% DDG, DRC with 25% DDG, SFC with 0% DDG, and SFC with 25% DDG. There were no significant grain processing by distiller's grain interactions observed in main effects. In conclusion optimum flake density was 360 g/L, feeding distiller's grains has a greater value in DRC diets vs. SFC diets, roughage level and type are important in formulating finishing diets, roughage can be reduced when feeding distiller's grains, and ruminal ammonia, and pH are decreased and ruminal lactate is increased when feeding DDG and SFC.

Doctor of Philosophy / Department of Diagnostic Medicine/Pathobiology / Tiruvoor G. Nagaraja / Escherichia coli O157 is a major foodborne pathogen that causes enteritis in humans ranging in severity from mild to bloody diarrhea to hemolytic uremic syndrome and even death. Cattle are asymptomatic carriers and fecal shedding of the organism is the major source of contamination of food and water for human infections. Distiller’s grains (DG) are ethanol fermentation co-products that are valuable feed ingredients for use in cattle diets. Previous research suggests an association between feeding DG and an increased fecal shedding of Escherichia coli O157:H7. The objectives of the research were to evaluate fecal E. coli O157:H7 prevalence and concentration in cattle fed diets with and without DG, determine if the association was dependent on inclusion level or form (wet or dried), evaluate the association in populations of cattle at harvest, and evaluate a potential intervention strategy. Our results indicated that cattle fed DG had a higher prevalence and shed a higher concentration of E. coli O157 than cattle fed diets without DG. The relationship was not dependent on the DG form, however, it was affected by the inclusion level of DG in the diet. Cattle that were fed 40% DG had a higher E. coli O157:H7 prevalence than cattle fed control or 20% DG diets and cattle fed 20% DG had a prevalence that was not statistically different from control cattle. The same response was observed in a subpopulation of cattle, termed super-shedders, which shed E. coli O157:H7 at higher concentrations than the general population. At harvest, we did not find differences in E. coli O157:H7 or super-shedder prevalence between cattle fed diets with or without DG, however, study design limitations affected the power of the study. Finally, previous work had shown that cattle fed dry-rolled grains had a decreased prevalence of E. coli O157:H7 when compared to cattle fed steam-flaked grains. We evaluated the effect of feeding DG and dry-rolled corn (DRC), alone or in combination, and observed no difference in E. coli O157 prevalence between cattle fed either DG or DRC diets. In conclusion, DG supplementation increased the prevalence and concentration of E. coli O157:H7 in cattle.

Master of Science / Department of Animal Sciences and Industry / John Jaeger / Cattle grazing dormant native range (< 7% crude protein; CP) require supplementation of additional protein to sustain body weight (BW) and body condition score (BCS). Daily delivery of these supplements is an economic burden to cattle producers faced with challenging economic circumstances. Supplementing cows infrequently (as little as once/week) has produced equivalent BW and BCS changes compared to daily delivery. Dried distiller’s grains with solubles (DDGS) provides more ruminally-undegradable protein (RUP; 50-60%) compared to traditional oilseed-meal supplements (i.e. soybean meal) that are >50% ruminally-degradable protein (RDP). Therefore, our objective was to evaluate the effects of supplementation frequency on performance, reproductive success, eating behavior, and subsequent calf performance of spring-calving cows supplemented with DDGS. No differences in ending BW (P = 0.69) and BCS (P = 0.49), or changes in BW and BCS over the supplementation period (P = 0.82 and 0.70, respectively) were observed among cows supplemented every d, every 3 d, or every 6 d. Calf BW at birth, weaning weight (WW), and average daily gain (ADG) were similar among treatments (P = 0.19, 0.12, and 0.10, respectively). First-service conception rate (FSCR) and final pregnancy rate (PR) were also not affected by supplementation frequency (P = 0.62 and 0.76, respectively). The development of replacement heifers is a large expense for cow-calf producers. Improved breeding and heifer development strategies aimed at ensuring the success of replacement females have been developed but reproductive failure still remains a problem. The stress associated with breeding and handling procedures may decrease reproductive success. Therefore, the objective was to determine if intramuscular administration of flunixin meglumine (1.1 mg/kg BW) 14 days post-breeding would improve FSCR and PR in non-transported replacement heifers. Under the conditions of our study, flunixin meglumine did not improve (P = 0.87) first service conception rate above that of control heifers (41.2% and 42.3%, respectively). Final pregnancy rate also was not different between treatments and averaged 81.8% (P = 0.40).

The objective of this study was to determine the effect of nutrient density and housing on E. coli populations in beef and dairy production systems. In the first trial, sixty second trimester beef cows were housed in two different overwintering environments and provided dry hay which was either bale grazed or placed in a feed bunk. Selected pens had supplemented with dried distiller’s grain with soluble (DDGS; 2.5 kg/cow/every third day) or rolled barley (1 kg/cow/day). In the second trial, six rumen and caecal-cannulated, non-lactating, multiparous Holstein cows received one of the following diets: i) 70% forage ii) grain pellet or iii) alfalfa pellet. The latter two diets were formulated to induce subacute ruminal acidosis (SARA). All animals were randomly sorted to pens and treatments. Fecal samples were collected and cultured on selective media. E. coli were enumerated and three isolates were chosen for PCR to detect the presence of 18 selected genes encoding a range of virulence factors. These same isolates were tested for their ability to invade the human adenocarcinoma epithelial cell line HT-29. Diet did not significantly affect E. coli abundance but did influence the prevalence of virulence genes involved in adhesion of bacteria to epithelial surfaces. When the diet contained grain, cows shed isolates which were more invasive than those from cows in the other treatments. The data suggest that diet may affect the abundance of E. coli shed in the feces and increase the presence of E. coli harbouring particular virulence genes that mediate adhesion and invasion of epithelial surfaces.

The objective of this study was to determine the effect of nutrient density and housing on E. coli populations in beef and dairy production systems. In the first trial, sixty second trimester beef cows were housed in two different overwintering environments and provided dry hay which was either bale grazed or placed in a feed bunk. Selected pens had supplemented with dried distiller’s grain with soluble (DDGS; 2.5 kg/cow/every third day) or rolled barley (1 kg/cow/day). In the second trial, six rumen and caecal-cannulated, non-lactating, multiparous Holstein cows received one of the following diets: i) 70% forage ii) grain pellet or iii) alfalfa pellet. The latter two diets were formulated to induce subacute ruminal acidosis (SARA). All animals were randomly sorted to pens and treatments. Fecal samples were collected and cultured on selective media. E. coli were enumerated and three isolates were chosen for PCR to detect the presence of 18 selected genes encoding a range of virulence factors. These same isolates were tested for their ability to invade the human adenocarcinoma epithelial cell line HT-29. Diet did not significantly affect E. coli abundance but did influence the prevalence of virulence genes involved in adhesion of bacteria to epithelial surfaces. When the diet contained grain, cows shed isolates which were more invasive than those from cows in the other treatments. The data suggest that diet may affect the abundance of E. coli shed in the feces and increase the presence of E. coli harbouring particular virulence genes that mediate adhesion and invasion of epithelial surfaces.

Master of Science / Department of Animal Sciences and Industry / James S. Drouillard / Three trials were conducted using dried distiller's grains with solubles (DDGS) to evaluate effects on feedlot performance, carcass characteristics, ruminal fermentation, and diet digestibility in cattle fed steam-flaked corn-based diets. In trial 1, crossbred yearling heifers were used in a finishing trial to evaluate interactions between corn-DDGS feeding levels and roughage source (alfalfa hay vs corn silage) in terms of impact on feedlot performance and carcass characteristics. Experimental diets were based on steam-flaked corn and contained 0% DDGS with 6% alfalfa hay (AH), 0% DDGS with 10% corn silage (CS), 25% DDGS with 6% AH, or 25% DDGS with 10% CS (DM basis). Results indicated no interaction between levels of DDGS and roughage source. Heifers fed DDGS as a partial replacement for steam-flaked corn had similar growth performance and carcass merit compared to heifers fed diets without DDGS. Corn silage and alfalfa hay were comparable roughages when a portion of steam-flaked corn was replaced with DDGS. The second trial was a companion metabolism study in which ruminal fermentation characteristics and diet digestibility were examined in 12 cannulated Holstein steers fed steam-flaked corn finishing diets with or without DDGS, using alfalfa hay or corn silage as roughage sources. Diets were similar to those fed in the performance study and consisted of steam-flaked corn with 0 or 25% DDGS (DM basis) and 6% AH or 10% CS (DM basis). Feeding DDGS decreased ruminal pH and ruminal ammonia concentrations, and digestion of DM and OM were less compared to diets without DDGS. The decrease in digestibility was largely attributable to poorer digestion of CP and, to a lesser extent, a reduction in starch digestion. The third study was designed to investigate effects of pH (5.0, 5.5, and 6.0) on in vitro fermentative activity by ruminal microorganisms from cattle adapted to a finishing diet containing 25% DDGS (DM basis). Higher pH led to greater dry matter disappearance in vitro (P < 0.01). DDGS can be an effective substitute for steam-flaked corn. Efforts to address low ruminal pH and low ruminal ammonia may prove beneficial for improving value of DDGS as cattle feed.

Master of Science / Department of Animal Sciences and Industry / James S. Drouillard / A trial was conducted replacing portions of steam-flaked corn with either dry-rolled corn or dried distiller’s grains with solubles to evaluate effects on performance, carcass characteristics, carcass composition, meat color stability, and meat sensory attributes. Seven hundred crossbred yearling heifers (302 ± 65 kg initial BW) were used in a randomized complete block experiment with a 2 x 2 factorial arrangement of treatments. All diets contained steam-flaked corn (SFC), and factors consisted of the levels of dry-rolled corn (DRC; 0 or 25%) and dried corn distiller’s grains with solubles (DDGS; 0 or 25%). Results revealed no interactions between DRC and DDGS in terms of effects on feedlot performance, and only minor interactive effects were observed for carcass characteristics and meat quality attributes. Feedlot performance and carcass characteristics were not affected by the addition of DRC or DDGS (P > 0.05). Carcass composition and meat quality attributes were measured to determine if fat content of carcasses was altered by feeding DDGS. Diet had no significant effects, as carcasses from the four treatments contained similar amounts of separable portions of muscle, adipose, and bone; and similar percentages of protein, moisture, and ether extract. Compositions of both adipose and muscle tissue were evaluated to assess differences in fatty acid profile. Minimal effects were noted on the fatty acid profiles of the muscle and adipose tissue from cattle fed DDGS or DRC. Feeding cattle DDGS decreased alpha tocopherol (vitamin E) content of meat (P < 0.05). Meat quality attributes were largely unaffected by addition of DRC or DDGS to the diet, as retail color display life, lipid oxidation, sensory attributes, and heterocyclic amine concentrations were not different among treatments. Overall, DRC or DDGS can replace portions of SFC without negatively altering feedlot performance, carcass characteristics, meat composition, or meat quality attributes.