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The effects of zilpaterol hydrochloride (ZH) on blood metabolites and fatty acid profiles of plasma and adipose tissue were evaluated in crossbred finishing steers (n = 18, BW 639 ± 12.69 kg) that were stratified by BW and randomly assigned, within strata (block), to receive 0 (control) or 8.33 mg/kg diet DM ZH. Cattle were fed once daily ad libitum in individual feeding pens (9 pens/treatment). Zilpaterol hydrochlo- ride was fed for 23 d and withdrawn 3 d before harvest. Blood samples and measures of BW were taken on d 0, 7, 14, and 21. Concentrations of β-hydroxybutyrate (BHB), glucose, and lactate were determined from whole blood. Nonesterified fatty acids, urea nitro- gen (PUN), glucose, lactate, and long-chain fatty acid (LCFA) concentrations were analyzed from plasma. Postharvest, adipose tissue samples (approximately 20 g) from subcutaneous fat covering the lumbar ver- tebrae were collected after 48 h of refrigeration and analyzed for LCFA profiles. Feeding ZH decreased DMI by 8% (P = 0.03) but did not affect BW gain or efficiency (P = 0.83 and P = 0.56, respectively). Addition of ZH resulted in greater HCW, dressing per- centage, and LM area (P = 0.02, P = 0.08, and P = 0.07, respectively) but did not influence other carcass traits (P > 0.10). A ZH × d interaction was observed for PUN and whole-blood glucose concentrations (P = 0.06), in which concentrations decreased in cattle receiving ZH. Nonesterified fatty acids, BHB, plasma glucose, whole-blood, and plasma lactate concentrations were unaffected by ZH (P > 0.10). Zilpaterol hydrochloride increased plasma concentrations of elaidic (P = 0.03), vaccenic (P = 0.006), and docosapentaenoic acids (P = 0.08), but LCFA concentrations of adipose tissue were unaffected (P > 0.10), suggesting no preferential oxidation of specific fatty acids. In conclusion, ZH sup- plementation decreased PUN concentration possibly due to decreased muscle catabolism, but components of blood related to lipid oxidation were unaffected.

Twelve ruminally cannulated crossbred Angus steers were used to evaluate ruminal fermentation characteristics and diet digestibility when 30% (DM) corn dried distillers grains with solubles (DDGS) containing 0.42 or 0.65% (DM) of dietary S was incorporated into finishing diets based on steam-flaked corn (SFC) or dry-rolled corn (DRC). The study was a replicated, balanced randomized incomplete block design with a 2 × 2 factorial arrangement of treatments. Factors consisted of dietary S concentration (0.42 and 0.65% of DM; 0.42S and 0.65S, respectively) and grain processing method (SFC or DRC). The 0.65S concentration was achieved by adding H(2)SO(4) to DDGS before mixing rations. Steers were assigned randomly to diets and individual, slatted-floor pens, and fed once daily for ad libitum intake. Two 15-d experimental periods were used, each consisting of a 12-d diet adaptation phase and a 3-d sample collection phase. Samples were collected at 2-h intervals postfeeding during the collection phase. Ruminal pH was measured immediately after sampling, and concentrations of ruminal ammonia and VFA were determined. Fecal samples were composited by steer within period and used to determine apparent total tract digestibilities of DM, OM, NDF, CP, starch, and ether extract. Feeding 0.65S tended (P = 0.08) to decrease DMI but resulted in greater apparent total tract digestibilities of DM (P = 0.04) and ether extract (P = 0.03). Ruminal pH increased (P < 0.05) in steers fed 0.65S diets, which may be attributable, in part, to decreased (P = 0.05) VFA concentrations and greater (P < 0.01) ruminal ammonia concentrations when 0.65S was fed, compared with feeding 0.42S. These effects were more exaggerated in steers fed DRC (interaction, P < 0.01), compared with steers fed SFC. Steers fed DRC-0.65S had greater (P < 0.01) acetate concentration than steers fed DRC-0.42S, but acetate concentration was not affected by S concentration when SFC was fed. Propionate concentration was decreased (P < 0.01) in steers fed SFC-0.65S compared with steers fed SFC-0.42S, but dietary S concentration had no effect on propionate concentration when DRC was fed. Butyrate concentration was less (P < 0.01) in steers fed 0.65S diets than in steers fed 0.42S. Lactate concentrations tended (P = 0.06) to decrease in steers fed 0.65S diets. Feeding DDGS with increased S concentration may decrease feed intake and ruminal VFA concentration but increase ruminal ammonia concentration.

Crossbred yearling steers (n=80; 406 ± 2.7 kg of BW) were used to evaluate the effects of S concentration in dried distillers grains with solubles (DDGS) on growth performance, carcass characteristics, and ruminal concentrations of CH(4) and H(2)S in finishing steers fed diets based on steam-flaked corn (SFC) or dry-rolled corn (DRC) and containing 30% DDGS (DM basis) with moderate S (0.42% S, MS) or high S (0.65% S, HS). Treatments consisted of SFC diets containing MS (SFC-MS), SFC diets containing HS (SFC-HS), DRC diets containing MS (DRC-MS), or DRC diets containing HS (DRC-HS). High S was achieved by adding H(2)SO(4) to DDGS. Ruminal gas samples were analyzed for concentrations of H(2)S and CH(4). Steers were fed once daily in quantities that resulted in traces of residual feed in the bunk the following day for 140 d. No interactions (P ≥ 0.15) between dietary S concentration and grain processing were observed with respect to growth performance or carcass characteristics. Steers fed HS diets had 8.9% less DMI (P 0.05) on G:F or carcass characteristics. Cattle fed HS had greater (P < 0.001) ruminal concentrations of H(2)S than cattle fed MS. Hydrogen sulfide concentration was inversely related (P ≤ 0.01) to ADG (r=-0.58) and DMI (r=-0.67) in cattle fed SFC, and to DMI (r=-0.40) in cattle fed DRC. Feeding DDGS that are high in dietary S may decrease the DMI of beef steers and compromise the growth performance and carcass characteristics of feedlot cattle.

Introduction With increasing feed costs, producers may be able to utilize forage resources to help cattle gain weight before entering a high-concentrate finishing phase. In theory, heavy stocker cattle need less time on feed before slaughter compared to lighter weight cattle; however, research determining the impact of a short feeding system on product quality is limited. Therefore, the purpose of this research was to investigate the impact of a shortened, high-concentrate feeding period on carcass characteristics and meat quality traits of heavy yearling stocker cattle.

Introduction Distillers grains with solubles are becoming an increasingly important staple of cattle diets because of rapid expansion of the fuel ethanol industry. Sulfuric acid often is used in ethanol production processes to clean and control the pH of fermenters. Consequently, distillers grains with solubles can occasionally contain high sulfur concentrations. Within the rumen, sulfur is converted to hydrogen sulfide gas by ruminal microbes. Hydrogen sulfide is eructated from the rumen and subsequently aspirated into the lungs; excess amounts of hydrogen sulfide can cause polioencephalomalacia (brainers). Polioencephalomalacia is characterized by increased respiration, decreased feed intake, listlessness, muscular incoordination, progressive blindness, and necrosis of brain tissue. Elevated sulfur levels also may have deleterious effects on cattle growth performance and carcass characteristics. The objective of this study was to evaluate effects of sulfur content in dried distillers grains with solubles on ruminal gas concentrations, feedlot performance, and carcass characteristics of finishing steers fed diets based on steam-flaked corn or dry-rolled corn.

Introduction Expansion of the renewable fuels industries has increased availability of by-products that are well suited for use as cattle feed. Glycerin is among the principal by-products of biodiesel production, comprising approximately 10% (by weight) of the soybean oil that is used to manufacture soy-based diesel fuel. Our previous research evaluated effects of including between 0% and 16% glycerin in flaked-corn finishing diets and revealed that optimal growth performance was achieved with 2% glycerin addition. Our laboratory experiments have suggested that even lower levels of glycerin may be effective at stimulating digestion. Therefore, the objective of this study was to evaluate effects of low levels of glycerin in the diet on performance and carcass characteristics of finishing cattle. Furthermore, because distillers grains and other by-products are increasingly common in feedlot rations, we opted to evaluate glycerin in corn-based finishing diets as well as in diets that consisted of a combination of corn grain, distillers grains, and soybean hulls.

Introduction Requirements for elemental sulfur in feedlot diets have been established to be approximately 0.15% with a maximum upper threshold of 0.40% of diet dry matter. Feeding ethanol fermentation by-products, such as distillers grains with solubles, that are high in sulfur can result in dietary sulfur levels that exceed the recommended maximum. Previous studies indicated that dietary sulfur influenced the site and extent of fiber and protein digestion. The objective of this study was to evaluate ruminal fermentation characteristics and diet digestibility when 30% (dry matter basis) dried distillers grains with solubles with various levels of sulfur was incorporated into finishing diets based on steam-flaked corn or dry-rolled corn.

Two studies were conducted to evaluate effects of dried distillers grains with solubles (DDGS) and alfalfa hay (AH) or corn silage (CS) on feedlot performance, carcass characteristics, ruminal fermentation, and diet digestibility in cattle fed steam-flaked corn (SFC) diets. In trial 1, crossbred heifers (n = 358; BW = 353 +/- 13 kg) were used in a finishing trial to evaluate interactions between corn-DDGS and roughage source (AH or CS) in terms of impact on feedlot performance and carcass characteristics. Experimental diets (DM basis) consisted of SFC and 11% CS without DDGS (SFC-CS), SFC and 11% CS with 25% DDGS (DDGS-CS), SFC and 6% AH without DDGS (SFC-AH), and SFC with 25% DDGS and 6% AH (DDGS-AH). Heifers were fed for ad libitum intake once daily for 97 d. Results indicated no interaction between DDGS and roughage source with respect to animal performance. Feeding DDGS did not affect ADG (P = 0.19), DMI (P = 0.14), or feed conversion (P = 0.67). Heifers fed CS had greater DMI than those fed AH (P = 0.05), but ADG (P = 0.56) and G:F (P = 0.63) were not different. There were no differences among treatments with respect to HCW, dressing percentage, subcutaneous fat thickness, quality grades, or yield grades (P > 0.20). Cattle fed CS tended (P = 0.10) to have greater marbling scores than those fed AH. There was an interaction (P = 0.02) between roughage and DDGS with respect to incidence of liver abscess. The greatest incidence was observed in cattle fed diets without DDGS when CS was fed, and the least was observed in cattle fed diets without DDGS when AH was used. In the second trial, ruminal fermentation characteristics and diet digestibility were examined in 12 cannulated Holstein steers fed similar diets to those fed in the finishing trial. Ruminal pH for all treatments was below 5.8 for 14 h after feeding. Acetate:propionate ratios were less (P = 0.02) in steers fed 25% DDGS but had greater (P = 0.02) ruminal lactate concentrations compared with cattle fed 0% DDGS. Feeding 25% DDGS decreased (P < 0.01) ruminal ammonia concentrations, and digestion of DM and OM was less (P < 0.01) compared with diets without DDGS. The decrease in digestibility was largely attributable to decreases in digestion of CP (P = 0.03) and NDF (P < 0.01). Feeding strategies aimed at increasing ruminal pH and ruminally available protein may improve digestion of DDGS in steam-flaked corn-based finishing diets.

Introduction Zilpaterol-HCl (Zilmax; Intervet/Schering-Plough Animal Health, Millsboro; DE) is an orally active β2-adrenergic agonist that is approved for use in feedlot cattle at the rate of 7.56 g/ton of diet dry matter for the final 20 to 40 days on feed. The minimum withdrawal time for Zilmax is 3 days. Zilmax increases hot carcass weight and dressing percentage, primarily as a result of increasing lean muscle mass and decreasing body fat. Zilmax also decreases marbling and increases shear-force values (i.e., less tender) of steaks. This study was conducted to determine whether the benefits of Zilmax would be retained with longer withdrawal times while overcoming undesirable effects on shear force and marbling.

Crossbred heifers (n = 373; 421.6 kg +/- 28.9) were fed finishing diets containing 0, 2, 4, 8, 12, or 16% crude glycerin (DM basis). Diets consisted of steam-flaked corn with 6% alfalfa hay and 1.2% urea and provided 300 mg of monensin, 90 mg of tylosin, and 0.5 mg of melengestrol acetate per animal daily. Cattle were stratified by BW and allocated randomly, within strata, to concrete-surfaced feedlot pens each containing 6 to 7 heifers, with 9 pens per dietary treatment. Cattle were transitioned from the control diet to diets containing increasing proportions of glycerin over a period of 10 d. Cattle had ad libitum access to feed, and diets were delivered once daily throughout the 85-d trial period. As the concentration of glycerin increased, DMI decreased linearly (P < 0.001). Heifers fed 0, 2, 4, 8, 12, and 16% glycerin had ADG of 1.19, 1.34, 1.29, 1.25, 1.17, and 1.03 kg, respectively (linear, P = 0.013; quadratic, P = 0.010). Feeding glycerin had a quadratic effect on G:F, and G:F was optimal when glycerin was fed at 2% of the diet (quadratic, P = 0.046). Glycerin increased the final BW by 12.7, 8.1, and 5.3 kg when fed at 2, 4, and 8% of the diet, respectively, but reduced the final BW by 1.9 and 14.3 kg when included at 12 and 16% of the diet (linear, P = 0.009; quadratic, P = 0.006). Similarly, HCW increased by 8.1, 5.1, and 3.3 kg when glycerin was fed at 2, 4, and 8% of the diet, respectively, but were 1.2 and 9.1 kg less than controls when glycerin was fed at 12 and 16%, respectively (linear, P = 0.009; quadratic, P = 0.006). Longissimus muscle area decreased linearly as glycerin concentrations increased (P < 0.013). Feeding glycerin resulted in linear decreases in subcutaneous fat over the 12th rib and marbling scores (P = 0.045). Glycerin tended to decrease the percentage of cattle grading USDA Choice (P = 0.084) and increase the percentage of cattle grading USDA Select. Adding glycerin to cattle-finishing diets improved BW gain and feed efficiency, particularly when added at concentrations of 8% or less on a DM basis.

Introduction Rapid expansion of fuel ethanol production has made available abundant supplies of distillers grains with solubles, which are well-suited as a substitute for cereal grains in finishing cattle diets. Several recently reported experiments have revealed that feeding distillers grains may have adverse effects on carcass value as a result of the tendency to produce carcasses with lower quality grades and/or higher yield grades. The effects on quality grade have been most evident in flaked-grain diets, but effects on yield grade are more or less independent of the type of grain fed. In Kansas, two common methods for processing grains are steam flaking and dry rolling. Thus, feeding cattle distillers grains with different grain processing types is an important consideration for feedlots. Our experiment was designed to evaluate meat quality and composition in heifers fed flakedcorn diets containing dry-rolled corn and/or dried corn distillers grains.

Introduction Upon arrival in feedlots, cattle normally must be adapted to high-concentrate diets. The microbial population in the rumen of incoming cattle normally is suited to digestion of forages, and when cattle are transitioned onto concentrate diets, opportunistic bacteria that produce lactic acid can proliferate rapidly, leading to excesses of lactic acid in the rumen. High levels of lactic acid in the rumen may cause mild to severe acidosis. Megasphaera elsdenii is a lactate-utilizing bacterium that normally is present in rumens of cattle that have been adapted to high-grain diets, but numbers of the organism are relatively low during the step-up phase. Increasing the numbers of lactate-utilizing bacteria in newly arrived cattle by orally dosing with M. elsdenii may be a useful means of reducing the risk of ruminal acidosis in feedlot cattle. Our objectives were to evaluate ruminal parameters and determine efficacy of increasing ruminal populations of lactateutilizing bacteria in cattle following an abrupt diet change and administration of 10 mL (low dose), 100 mL (medium dose), or 1000 mL (high dose) of a culture containing 1.62 × 108 CFU/mL of live M. elsdenii compared with a control group given a placebo without live Megasphaera.

Introduction Increased ethanol production in the United States has increased availability of by-products, giving producers an alternative to cereal grains. The by-product we evaluated was dried corn distillers grains with solubles. Research has been conducted at Kansas State University to evaluate the quantity of distillers grains that can be added to a finishing diet without negatively affecting feedlot performance or carcass value. Feeding cattle distillers grains is an important option for feedlots to consider. The second issue that has arisen is the energy costs associated with processing grains. In Kansas, two of the more common methods for processing grains are steam flaking and dry rolling. Previous research has shown that the nutritive value of distillers grains can be influenced by grain processing method. This experiment was designed to evaluate feedlot performance and carcass merit in heifers fed flaked-corn diets with added dry-rolled corn and/or dried corn distillers grains.

Introduction European starlings (Sturnus vulgaris) were first introduced to the United States in the late 1800s. It is believed that the starlings were imported from Europe and released in New York City’s Central Park so that all of the birds mentioned in Shakespeare’s works would inhabit the new country. For the next 50 years, the starling population grew exponentially; by 1942, starlings had spread to the West Coast. Starlings are not considered migratory and remain in the same general area year round; however, some may migrate several hundred miles. During much of the year, the inconspicuous starlings disperse into small flocks and feed on seeds, fruits, and insects. During winter months, starlings form flocks of several hundred up to 750,000 birds that share feeding and roosting sites. These large flocks prefer to roost in coniferous trees, which provide protection from wind and adverse weather conditions. Previous research has documented that a 3-oz starling consumes nearly 2 lb of feed in a 30-day period. Commercial feedlots have been infested with large populations of starlings during winter months. The attraction to feedlots is due to open feed bunks that provide a convenient source of feed. Currently, there are limited means for controlling starlings in feedlots. The objective of our experiment was to compare susceptibility of different rations to depredation by starlings.

Two experiments evaluated the effects of conventional and natural feedlot management systems (MS) on ractopamine-HCl (RAC) response in yearling steers. Feedlot performance, carcass characteristics, skeletal muscle gene expression, and circulating IGF-I concentrations were measured. The conventional system included a combined trenbolone acetate and estradiol implant, Revalor-S (IMP), as well as monensin-tylosin feed additives (IA). Treatments were arranged in a 2 x 2 factorial and included: 1) natural (NAT): no IMP-no IA, no RAC; 2) natural plus (NAT+): no IMP-no IA, RAC; 3) conventional (CON): IMP-IA, no RAC; and 4) conventional plus (CON+): IMP-IA, RAC. In Exp. 1, one hundred twenty crossbred steers (initial BW = 400 +/- 26 kg) were allotted randomly to treatment in a randomized complete block design (BW was blocking criteria); pen was the experimental unit. In Exp. 2, twenty-four individually fed crossbred steers (initial BW = 452 +/- 25 kg) were used in a randomized complete block design (BW was blocking criteria) and assigned to the same treatments as Exp. 1, with 6 steers/treatment. In Exp. 2, serum was harvested on d 0 and 31 and within the 28-d RAC feeding period, at d 0, 14, and 28. Longissimus biopsy samples were taken on d 0, 14, and 28 of the RAC feeding period for mRNA analysis of beta-adrenergic receptors and steady-state IGF-I mRNA. In Exp. 1, ADG, G:F, final BW, and HCW were greatest for CON+ (P 0.10). Circulating IGF-I concentration was increased on d 31 by the conventional MS, and concentration was greater throughout the study than NAT steers (P 0.40). Management system did not affect beta(1)-AR, beta(2)-AR, beta(3)-AR, or IGF-I mRNA (P > 0.18), yet a trend (P = 0.06) for MS x RAC for beta(2)-AR mRNA was detected. These results indicate that response to RAC is affected by feedlot management practices.

Two-thousand two-hundred fifty-two yearling steers (690 lb) were used to evaluate the effects of Optaflexx and days on feed on finishing steer performance and carcass characteristics. Treatment groups included serial harvest dates of 150, 171, or 192 days. Within each harvest date, steers either received Optaflexx (200 mg/steer daily of ractopamineHCl) for the final 28 days, or did not receive Optaflexx. All steers were initially implanted with Revalor-IS and were re-implanted with Revalor-S after 75 days on feed. At harvest, muscle samples from the inside round were obtained for mRNA analysis of the βadrenergic receptors (AR). Optaflexx increased daily gains, hot carcass weight, and ribeye area, and improved feed efficiency. Optaflexx did not affect dressing percentage, USDA yield grade, or quality grade. Optaflexx did not change overall feed intake across the entire feeding period, but feed intake was increased during the 28-day period that steers received Optaflexx. As expected, greater days on feed decreased daily gains, overall feed intake, and the number of yield grade 1 and 2 carcasses, and worsened feed efficiency. Also, greater days on feed increased hot carcass weight, dressing percentage, and the number of prime and choice carcasses, as well as the number of yield grade 4 and 5 carcasses. Increasing days on feed decreased the abundance of mRNA for β1-AR and β3-AR, and increased the abundance of β2AR mRNA. Optaflexx had no effect on abundance of mRNA for β1-AR or β3-AR, but it increased the abundance of mRNA for β2-AR. Optaflexx may affect expression of the β2-AR gene in skeletal muscle, which could impact the performance responses to Optaflexx feeding in steers.

Regrowth and old-growth Douglas-fir stands were sampled for ground dwelling beetles using pitfall traps in 1982, 1983 and 1999. Species richness and abundance was compared within and among years, plots, and age of forest using multivariate techniques. Representatives of 49 families and 224 taxa were collected for a total of 11,191 specimens. The abundance and species richness of ground dwelling beetles suggested four notable relationships. First, different ages of forest had significantly different beetle communities. For instance, the herb stage regrowth stands supported a number of seral specialists including: Microlestes nigrinus Mannerheim and Trachypachus holmbergi Mannerheim. Second, specifically defined plant communities were associated with unique beetle communities. Ordination analysis showed that the grouping of stands, based on beetle communities, was correlated with differences in vegetative characteristics. Third, over a 17-year-period, beetle communities in old-growth stands remained relatively stable while beetle communities in regrowth stands exhibited a high degree of change. Ordination analysis grouped old-growth stands regardless of year sampled, while young seral stands changed significantly in regards to their ordination position depending on sampling year. Fourth, beetle communities in regrowth stands changed in a manner that paralleled the predictable transformation of young plant communities into mature forest stands. Ordination analyses found that beetle communities in the herb stage regrowth stands of 1982 had changed significantly and exhibited characteristics of beetle communities in tree stage regrowth stands.

Introduction Grazing stocker cattle on low-quality forages is a common practice in Kansas; however, animal performance typically is modest. Due to the increasing availability of ethanol co-products, producers may be able to use dried distillers grains with solubles (DDGS) as a protein source to help increase body weight of stocker cattle grazing native tallgrass pastures during the late summer and fall. Therefore, the purpose of this research was to investigate the impact of feeding DDGS to heavy stocker cattle during late summer and fall and to document its effects on animal performance and subsequent carcass characteristics.

Introduction Using a growth promotant at the correct time of finishing is critical for maximizing profit potential. Previous studies have shown that zilpaterol-HCl (Zilmax; Intervet/ Schering-Plough Animal Health, Millsboro, DE) improves carcass characteristics. The objective of this study was to determine effects of prior body composition on subsequent changes in carcass weight, fatness, and muscle in heifers fed Zilmax so producers can introduce Zilmax at the level of finish that will result in the most desirable response. We hypothesized that fatter heifers use fat as the fuel for muscle growth.

Introduction Expansion of the biodiesel industry has increased supplies of crude glycerin available for livestock feeding. Catalyzed reactions between methanol and triglycerides from vegetable oils, such as soybean oil, yield biodiesel and a coproduct, crude glycerin. Approximately 10% of the weight of soybean oil used to produce biodiesel becomes glycerin. Limited work has been conducted to understand metabolism of glycerin in ruminant livestock. In previous studies at Kansas State University, feeding crude glycerin at 8% or less of the diet improved cattle performance. Subsequent laboratory experiments indicated that low levels of glycerin may improve ruminal fermentation. This study was conducted to determine whether adding low levels of glycerin to feedlot diets could affect diet digestibility.

Plant oils contain large amounts of triglycerides that will react to a catalyst, such as methanol. The transesterification reaction between the oil and alcohol will produce approximately 10% crude glycerin and 90% biodiesel. Crude glycerin is distilled for use in human products such as soaps, cosmetics, and moisturizers, but the usefulness of glycerin as a feed source for livestock is unclear. Rapid expansion of the biodiesel industry has created excess supplies of crude glycerin. It is thought that glycerin can be used in ruminant diets to decrease feed costs, but crude glycerin from biodiesel production can contain various levels of methanol, which can be toxic to livestock at increased levels. The purpose of this experiment was to determine the effects of feeding crude glycerin derived from soybean oil in steam-flaked corn finishing diets fed to beef cattle.

Dried distiller’s grains with solubles (DDGS) are the main byproduct of dry milling, the process used most frequently for fuel ethanol production. DDGS consist of the spent grains following ethanol distillation and are high in protein, fat, fiber, and minerals. Alfalfa hay and corn silage are roughages most commonly included in feedlot diets and are one of the most expensive ingredients in feedlot diets on an energy basis. Comparing use of alfalfa hay and corn silage in conjunction with DDGS can provide useful information on how to obtain maximum benefit from these ingredients. Our objective was to evaluate the use of corn DDGS as a partial replacement for steam-flaked corn when corn silage or alfalfa hay were used in feedlot diets.

Escherichia coli O157 is an important foodborne pathogen and asymptomatic cattle serve as major reservoirs for human infection. We have shown a positive association between feeding distiller's grains and E. coli O157 prevalence in feedlot cattle. The objective of this study was to determine the effect of feeding dried distiller's grain (DDG) on faecal shedding of E. coli O157 in calves experimentally inoculated with E. coli O157. Holstein calves (five per treatment group), fed steam-flaked corn-based high-grain diets supplemented with 0% (control) or 25% DDG, were orally inoculated with a five-strain mixture (6 x 10(9) CFU/calf) of nalidixic acid-resistant (NalR) E. coli O157. Faecal samples were taken three times per week for 6 weeks to determine the prevalence and concentration of Nal E. coli O157. At the end of the study (day 43), calves were euthanized and necropsied. Ruminal, caecum, colon, and rectal contents, and rectoanal mucosal swab (RAMS) samples were collected at necropsy to determine NalR E. coli O157 concentration. There was a trend for an interaction between treatment and faecal sampling day. The concentration of NalR E. coli O157 in the faeces was significantly higher in faecal samples from calves fed DDG compared with control calves on days 35, 37, 39 and 42. At necropsy, the concentration of NalR E. coli O157 was higher in the caecum (P = 0.01), colon (P = 0.03) and rectum (P = 0.01) from calves fed DDG compared with control animals. The number of sites at necropsy positive for NalR E. coli O157 was higher in calves fed DDG compared with calves in the control treatment (P < 0.001). Our results indicate that E. coli O157 gut persistence and faecal prevalence increased in calves fed DDG, which potentially have important implications for food safety.

This report documents the results of the testing performed per POTP-001, for the Cross-Site Transfer Water Flush System. (HNF-1552, Rev. 0) The Flush System consists of a 47,000 gallon tank (302C), a 20 hp pump, two 498kW heaters, a caustic addition pump, various valves, instruments, and piping. The purpose of this system is to provide flush water at 140 F, 140gpm, and pH 11-12 for the Cross-Site Transfer System operation.