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Grazing Cover Crops As An Alternative To Fallow And The Interaction Between Corn Processing Method And Condensed Distillers Solubles, Alex H. Titlow

Department of Animal Science: Dissertations, Theses, and Student Research

Recently, producers in dryland wheat farming regions have made a shift from the typical winter wheat fallow rotation to a no-till system paired with cover crops. Cover crops have been shown to minimize these problems associated with the conventional fallow and possibly provide a source of forage. A 2-year grazing study was conducted to evaluate forage quality and utilization of cover crops (CC) planted to replace fallow in no-till wheat systems compared to crested wheatgrass pastures (CWP). Hand clipped and diet samples were greater in digestibility and CP for CC compared to CWP. The NDF and ADF content of the …

The Impact Of Genetic Background On Body Temperature Regulation In Beef Cattle During Periods Of Heat And Cold Stress., Jeremy T. Howard

Department of Animal Science: Dissertations, Theses, and Student Research

Cattle are reared in environments that differ and vary greatly in climate, thus the ability to regulate body temperature across multiple environments is essential. However, inherent differences between animals do exist and can influence their response to extreme temperatures. The objectives of the current study were to model the impact of myostatin genotype (MG) on body temperature during heat and cold stress and conduct a genome-wide association study (GWAS) to better understand the genetic basis of body temperature regulation during extreme temperatures.

Crossbred steers and heifers (n= 239) with varying degrees of Piedmontese influence were fed in four groups over …

Utilization Of Corn Condensed Distillers Solubles And Forages In Management Systems For The Cow-Calf Enterprise, Jason M. Warner

Department of Animal Science: Dissertations, Theses, and Student Research

Of the annual expenses necessary to maintain a beef cow, feed and forage are the greatest and most variable. Thus, nutrition programs for cow-calf operations must be developed using economical feedstuffs that optimize cowherd performance. The corn dry-milling industry provides several feedstuffs that are often the most economical sources of energy and protein, but considerations for storage and handling are necessary. Two experiments evaluated an alternative form of storing corn condensed distillers solubles (CCDS) by applying to grass hay windrows before baling. Round bales were treated with either 0 or 20% (Exp. 1); or 0, 16, and 32% (Exp. 2) …

Nutrient Losses In Runoff From Feedlot Surfaces As Affected By Unconsolidated Surface Materials, John E. Gilley, Jason R. Vogel, Roger A. Eigenberg, David B. Marx, Brian L. Woodbury

Department of Biological Systems Engineering: Papers and Publications

Beef cattle feedlots contain unconsolidated surface materials (loose manure pack) that accumulate during a feeding cycle. The effects of varying amounts of unconsolidated surface materials on runoff nutrient losses are not well understood. The objectives of this study were to (1) compare runoff nutrient losses from feedlot surfaces containing varying amounts of unconsolidated surface materials, (2) determine if differences in runoff nutrient losses exist among rainfall simulation runs, (3) relate runoff nutrient losses to selected feedlot soil characteristics, and (4) identify the effects of varying runoff rate on nutrient loss rates from feedlot surfaces. This study was conducted on 0.75 …

Use Of A Complete-Feed Diet (Ramp) To Rapidly Transition Cattle To A Finishing Diet, C. J. Schneider, Brandon L. Nuttelman, Dirk Burken, Terry J. Klopfenstein, Galen E. Erickson

Department of Animal Science: Faculty Publications

A study evaluated transitioning cattle from RAMP to a finishing diet with fewer intermediate step diets and days fed during transition. Yearling crossbred steers (n = 390; BW = 341 ± 14 kg) were blocked and stratified by BW, and assigned randomly within strata to 40 feedlot pens, with 9 or 10 steers per pen. Treatments were different grain adaptation programs (27 or 28 d) involving blends of RAMP and finishing diet. A control adaptation program involved decreasing RAMP and increasing a 62.5% corn finishing diet (62.5% high moisture corn (HMC), 25% sweet bran, 7.5% alfalfa hay (AH), and 5% …

Use Of A Complete-Feed Diet (Ramp) In Grain Adaptation Programs Compared To Traditional Grain Adaptation Programs, C. J. Schneider, Brandon L. Nuttelman, Kelsey M. Rolfe Rolfe, William A. Griffin, Terry J. Klopfenstein, Galen E. Erickson

Department of Animal Science: Faculty Publications

A study evaluated using RAMP to adapt cattle to a high grain finishing diet. Yearling crossbred steers (n = 229; BW = 397 ± 28.4 kg) were consecutively weighed over 2 d, stratified by BW, and assigned randomly within strata to 18 feedlot pens, with 12 or 13 steers per pen. Treatments were imposed during grain adaptation (22 d) by decreasing RAMP (100 to 0%) and increasing finishing diet (0 to 100%). RAMP was fed either as a blend in a 1-diet system which was delivered twice daily (RAMP-1RS) or as 2 daily diets where RAMP was delivered in one …

Occurrence Of Hormonal Residues In Feedlot Cattle Waste, Terry L. Mader, Leslie J. Johnson, Shannon L. Bartelt-Hunt, Daniel D. Snow, William Kranz, Charles Shapiro, Simon Van Donk, David P. Shelton, David Tarkalson, T. C. Zhang, Steve Ensley

Department of Animal Science: Faculty Publications

Two identically designed studies were conducted in separate years at the UNL Haskell Agricultural Laboratory using 192 crossbred heifers (96/study). Within a study heifers (initial weight = 386kg) were randomly assigned to 2 groups (3 42.4 m × 14.6 m pens/group/year): 1) treatment (TRT) animals were administered synthetic hormones via subcutaneous implants [d 1, 36 mg zearalonal; d 35, 140 mg trenbolone acetate (TBA) and 14 mg of 17β-estradiol benzoate (Revalor-H)] and fed Melengesterol Acetate (MGA), and 2) control (CON) animals with no synthetic hormone provided. Throughout each study, feedlot pen surface samples were obtained from 4 equally-sized zones (5 …

Birth And Weaning Traits In Crossbred Cattle From Hereford, Angus, Norwegian Red, Swedish Red And White, Wagyu, And Friesian Sires, E. Casas, R. M. Thallman, L. V. Cundiff

Roman L. Hruska U.S. Meat Animal Research Center: Reports

The objective of this study was to characterize breeds representing diverse biological types for birth and weaning traits in crossbred cattle (Bos taurus). Gestation length, calving diffi culty, percentage of unassisted calving, percentage of perinatal survival, percentage of survival from birth to weaning, birth weight, weaning weight, BW at 205 d, and ADG was measured in 1,370 calves born and 1,285 calves weaned. Calves were obtained by mating Hereford, Angus, and U.S. Meat Animal Research Center III (1/4 Hereford, 1/4 Angus, 1/4 Pinzgauer, and 1/4 Red Poll) mature cows to Hereford or Angus (British breeds), Norwegian Red, Swedish Red and …

Opportunities And Challenges From The Use Of Genomic Selection For Beef Cattle Breeding In Latin America, Hugo H. Montaldo, Eduardo Casas, José Bento Sterman Ferraz, Vicente E. Vega-Murillo, Sergio Iván Román-Ponce

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

In 2009, Latin American countries had approximately 401 million cattle (29% of the world’s total cattle population) and produced 8.2 million tonnes of beef, equivalent to 29% of the world’s total production (FAO, 2011). Beef in Latin American countries is produced under widely differing climates (ranging from tropical to temperate), resources available (vegetation, food), types of markets, and genetic backgrounds of the animals. The main production systems are classified as beef and dual-purpose cattle. The genetic backgrounds of animals vary from purebred European (Bos taurus taurus) or Zebu (Bos taurus indicus) to crossbreeds (Figures 1 and …

Smooth Bromegrass Pasture Beef Growing Systems: Fertilization Strategies And Economic Analysis, A. K. Watson, T. J. Klopfenstein, Walter H. Schacht, G. E. Erickson, D. R. Mark, Matt K. Luebbe, K. R. Brink, Matthew A. Greenquist

Department of Animal Science: Faculty Publications

In recent years, prices for N fertilizer have increased dramatically, reducing net returns of fertilized pasture systems. A 5-yr study from 2005 to 2009 was conducted to evaluate management strategies and relative differences in profitability for 3 methods of backgrounding calves on smooth bromegrass pastures. Forty-five steers were used each year for a total of 225 animals in a randomized complete block design. Treatments included pastures fertilized in the spring with 90 kg N/ha (FERT), nonfertilized pastures with calves supplemented daily with dried distillers grains plus solubles (DDGS) at 0.6% of BW (SUPP), and control (CONT) pastures that had no …

Technical Note: Estimating Beef-Cattle Forage Demand: Evaluating The Animal Unit Concept, T. L. Meyer, L. A. Stalker, J. D. Volesky, D. C. Adams, R. N. Funston, T. J. Klopfenstein, Walter H. Schacht

Department of Animal Science: Faculty Publications

The objective of this experiment was to evaluate the effect of BW and physiological status of a beef animal on forage intake. The experiment was repeated over 2 yr with 6 replications of 3 treatments per year: cow-calf pair (CCP, BW = 629 kg), nonlactating cow (NLC, BW = 503 kg), and yearling steer (YS, BW = 305 kg). The CCP was treated as one unit, with the sum of cow BW and calf BW comprising CCP BW. Calves averaged 42 d of age and 73 kg at the start of the experiment each year. Animals were housed in individual …

Calving Date And Wintering System Effects On Cow And Calf Performance I: A Systems Approach To Beef Production In The Nebraska Sandhills, W. A. Griffin, L. A. Stalker, D. C. Adams, R. N. Funston, T. J. Klopfenstein

Department of Animal Science: Faculty Publications

A 4-yr study using 217 cows/yr (3/4 Red Angus, 1/4 Simmental) evaluated effects of calving date and wintering system on cow and calf performance from birth to harvest. Cows were assigned to 1 of 5 treatments: 1) March (Mar) calving cows wintered on native range, 2) Mar calving cows wintered on corn residue, 3) June (Jun) calving cows wintered on native range, 4) Jun calving cows wintered on corn residue, and 5) August (Aug) calving cows wintered on corn residue. Steers born in Mar entered the feedlot at weaning (calf-fed). Steers and heifers born in Jun and Aug were divided …

The Accuracies Of Dna-Based Estimates Of Genetic Merit Derived From Angus Or Multibreed Beef Cattle Training Populations, K. L. Weber, D. J. Drake, J. F. Taylor, Dorian Garrick, Larry A. Kuehn, R. Mark Thallman, Robert D. Schnabel, Warren M. Snelling, E. J. Pollak, A. L. Van Eenennaam

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Several organizations have developed prediction models for molecular breeding values (MBV) for quantitative growth and carcass traits in beef cattle using Bovine SNP50 genotypes and phenotypic or EBV data. Molecular breeding values for Angus cattle have been developed by IGENITY, Pfi zer Animal Genetics, and a collaboration between researchers from Iowa State University and the University of Missouri-Columbia (ISU/UMC). The U.S. Meat Animal Research Center (USMARC; Clay Center, NE) has also developed MBV for 16 cattle breeds using 2 multibreed populations, the Germplasm Evaluation (GPE) Program and the 2,000 Bull Project (2K_ALL), and 2 single breed subpopulations of …

Physiology And Endocrinology Symposium: How Single Nucleotide Polymorphism Chips Will Advance Our Knowledge Of Factors Controlling Puberty And Aid In Selecting Replacement Beef Females, W. M. Snelling, Robert Cushman, M. R. S. Fortes, A. Reverter, G. L. Bennett, J. W. Keele, L. A, Kuehn, T. G. Mcdaneld, Mark Thallman, M. G. Thomas

Roman L. Hruska U.S. Meat Animal Research Center: Reports

The promise of genomic selection is accurate prediction of the genetic potential of animals from their genotypes. Simple DNA tests might replace low-accuracy predictions for expensive or lowly heritable measures of puberty and fertility based on performance and pedigree. Knowing with some certainty which DNA variants (e.g., SNP) affect puberty and fertility is the best way to fulfill the promise. Several SNP from the BovineSNP50 assay have tentatively been associated with reproductive traits including age at puberty, antral follicle count, and pregnancy observed on different sets of heifers. However, sample sizes are too small and SNP density is too sparse …

Runoff Nutrient Loads As Affected By Residue Cover, Manure Application Rate, And Flow Rate, Chance Thayer, John E. Gilley, Lisa M. Durso, David B. Marx

Department of Biological Systems Engineering: Papers and Publications

Manure is applied to cropland areas with varying surface cover to meet single‐year or multiple‐year crop nutrient requirements. The objectives of this field study were to: (1) examine runoff water quality characteristics following land application of manure to sites with and without wheat residue, (2) compare the water quality impacts of land application of manure to meet 0‐, 1‐, 2‐, 4‐, and 8‐year P‐based requirements for corn, and (3) evaluate the effects of varying runoff rates on runoff nutrient loads. Three 30‐min simulated rainfall events, separated by 24 h intervals, were applied at an intensity of 70 mm h^{‐1 …}