Animal Sciences Commons^™

Effect Of Increasing Corn Silage Inclusion In Finishing Diets Cattle With Or Without Tylosin On Performance And Liver Abscesses, Hannah C. Wilson, Levi J. Mcphillips, Bradley M. Boyd, Andrea K. Watson, Jim C. Macdonald, Galen E. Erickson

Department of Animal Science: Faculty Publications

A pooled analysis was performed to evaluate whether corn silage fed at 15% or 45% of diet DM impacted liver abscesses prevalence at slaughter in five previous experiments. Cattle fed 15% corn silage had 7.8% abscessed livers compared to 4.1% for cattle fed 45% corn silage when all diets contained tylosin. While improved due to increased corn silage inclusion, the objective of the current finishing study was to determine the impact of silage inclusion in finishing diets with and without tylosin on performance and incidence of abscessed livers in beef cattle. A total of 640 (BW = 334 ± 25 …

Metaphylactic Antimicrobial Effects On Occurrences Of Antimicrobial Resistance In Salmonella Enterica, Escherichia Coli And Enterococcus Spp. Measured Longitudinally From Feedlot Arrival To Harvest In High-Risk Beef Cattle, Nathan S. Long, James E. Wells, Elaine D. Berry, Jerrad F. Legako, Dale R. Woerner, Guy H. Loneragan, Paul R. Broadway, Jeff A. Carroll, Nicole C. Burdick Sanchez, Samodha C. Fernando, Carley M. Bacon, Cory L. Helmuth, Taylor M. Smock, Jeff L. Manahan, Ashley A. Hoffman, Kristin E. Hales

Department of Animal Science: Faculty Publications

Aims: Our objective was to determine how injectable antimicrobials affected populations of Salmonella enterica, Escherichia coli and Enterococcus spp. in feedlot cattle.

Methods and Results: Two arrival date blocks of high-risk crossbred beef cattle (n = 249; mean BW = 244 kg) were randomly assigned one of four antimicrobial treatments administered on day 0: sterile saline control (CON), tulathromycin (TUL), ceftiofur (CEF) or florfenicol (FLR). Faecal samples were collected on days 0, 28, 56, 112, 182 and study end (day 252 for block 1 and day 242 for block 2). Hide swabs and subiliac …

Bovine Respiratory Disease Influences On Nutrition And Nutrient Metabolism, Clinton R. Krehbiel

Department of Animal Science: Faculty Publications

• Inflammation caused by bovine respiratory disease (BRD) continues to be one of the greatest challenges facing beef cattle producers and feedlot managers.

• BRD results in decreased intake, daily gain, and feed efficiency in feedlot calves, decreasing growth rate and increasing required days on feed.

• Morbidity caused by BRD has been associated with decreased hot carcass weight and poor carcass characteristics.

• Acute phase protein production in the liver, initiated by proinflammatory cytokines, may shift the priority for amino acid and energy use by the host animal during periods of sickness.

• Nutrient requirements for stressed calves seem …

Dehydrated Citrus Pulp Alters Feedlot Performance Of Crossbred Heifers During The Receiving Period And Modulates Serum Metabolite Concentrations Before And After An Endotoxin Challenge, J. T. Cribbs, B. C. Bernhard, T. R. Young, M. A. Jennings, N.C. Burdick Sanchez, J. A. Carroll, T. R. Callaway, T. B. Schmidt, B. J. Johnson, R. J. Rathmann

Department of Animal Science: Faculty Publications

English × Continental heifers (n = 180) were sourced in 2 loads (219.3 ± 16.0 and 221.4 ± 16.4 kg, respectively) from commercial auction barns to study the effects of feeding dehydrated citrus pulp (DCP) on feedlot performance of newly received heifers. A completely randomized block design was used with BW nested within arrival load and blocked by BW into 3 dietary treatments (36 pens, 5 heifers/ pen, 12 blocks, 3 pens/block, and 12 pens/treatment). Treatment diets contained 1) 0% DCP (control diet [CON]), 2) 10% DCP, or 3) 20% DCP on a DM basis. Diets containing DCP were exchanged …

The Economic Effects Of Sorting Cattle By Weight And Time Of Year Into Different Production Systems1, D. R. Adams, T. J. Klopfenstein, G. E. Erickson, D. R. Mark, Matt K. Luebbe, W. A. Griffin

Department of Animal Science: Faculty Publications

A 2-yr study using 288 steers each year was conducted to determine the economic effects of sorting and feeding genetically similar cattle in different production systems. Steers were purchased at weaning in November and assigned randomly into sorted or unsorted groups. Unsorted steers were assigned randomly to 1 of 3 production systems: calf-fed steers (enter feedlot after weaning), summer yearling, or fall yearling; n = 48 steers per system yearly. For sorted steers, the heaviest third were calf fed and the remaining steers grazed cornstalks during winter. After winter grazing, the heaviest half of those steers were fed as summer …

Effects Of Sorting Steers By Body Weight Into Calf-Fed, Summer Yearling, And Fall Yearling Feeding Systems, D. R. Adams, T. J. Klopfenstein, G. E. Erickson, W. A. Griffin, Matt K. Luebbe, Matthew A. Greenquist, J. R. Benton

Department of Animal Science: Faculty Publications

Two years of data (288 steers/yr) were used to determine if sorting cattle by BW into different production systems would decrease overweight carcasses (>431 kg) and hot carcass weight (HCW) variation. At receiving, steers were assigned randomly into sorted or unsorted groups (n = 144 steers/group). Within a group, steers were assigned to 1 of 3 feeding times: 1) calf-fed (entering the feedlot at receiving), 2) summer yearling (grazed during winter and entering the feedlot in May) and 3) fall yearling (grazed during winter and summer and entering the feedlot in September). Unsorted steers were assigned randomly to a …

Effects Of Ractopamine (Optaflexx) Fed In Combination With Melengestrol Acetate On Feedlot Heifer Performance, W. A. Griffin, G. E. Erickson, B. D. Dicke, T. J. Klopfenstein, R. J. Cooper, D. J. Jordon, R. S. Swingle, W. M. Moseley, G. E. Sides, D. J. Weigel

Department of Animal Science: Faculty Publications

Two commercial feedlot experiments were conducted to determine the effects of feeding melengestrol acetate (MGA) or MGA plus ractopamine (MGA+OPT) on the performance and carcass characteristics of finishing heifers. In Nebraska (Exp. 1), 1,807 heifers (337.3 ± 20.0 kg) and in Texas (Exp. 2), 1,964 heifers (331.5 ± 6.1 kg) were fed 0.4 mg of MGA daily. For heifers fed MGA+OPT, 200 mg of ractopamine was fed daily the last 29 (Exp. 2) or 36 d (Exp. 1). Live and carcass-adjusted performance data were collected. On a carcass-adjusted basis, G:F for the entire feeding period was improved (P < 0.01) by 1.7 and 3.7% in Exp. 1 and 2, respectively, for heifers fed MGA+OPT compared with MGA. For the last 29 to 36 d, G:F was increased (P < 0.02) by 8.1% (Exp. 1) or 27.2% (Exp. 2) on a carcass-adjusted basis for heifers fed MGA+OPT compared with MGA. Fat thickness, USDA YG, marbling score, LM area, and percentage USDA Choice were not different (P > 0.47) between …

Effect Of Corn Processing In Finishing Diets Containing Wet Distillers Grains On Feedlot Performance And Carcass Characteristics Of Finishing Steers, K. J. Vander Pol, Matthew A. Greenquist, G. E. Erickson, T. J. Klopfenstein, T. Robb

Department of Animal Science: Faculty Publications

Three-hundred sixty calf-fed steers (BW = 318 ± 15 kg) were used in a completely randomized design to evaluate corn processing methods in finishing diets containing wet distillers grains plus solubles (WDGS). Whole corn (WC) was compared with corn processed by different methods, consisting of dryrolled corn (DRC), high-moisture corn (HMC), a 1:1 DRC:HMC combination (DM basis), steam-flaked corn (SFC), and finely-ground corn (FGC). The SFC with a flake density of 0.33 kg/L was obtained from a commercial feedlot. Basal dietary ingredients consisted of ground alfalfa hay (5.6% of DM) and dry supplement (3.0% of DM), with the balance being …