Beef Science Commons^™

Annotating Gene Expression And Regulatory Elements In Tissues From Healthy Thoroughbred Horses And Identifying Candidate Mutations Associated With Perosomus Elumbis In An Angus Calf, Alexa Mckenna Barber

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

Genome annotation has a direct impact on the success of genomic studies. Transcriptome analyses and chromatin immunoprecipitation and sequencing (ChIP-seq) have been used to functionally annotate genomes. These methods can identify protein-coding genes, non-coding transcripts, and cis-regulatory elements across the genome. The primary objective of the first study was to functionally annotate the equine genome through the assessment of nine tissues: adipose, brain, heart, lamina, liver, lung, skeletal, muscle, testis, and ovary. In the first project, 150 bp, paired-end RNA sequencing (RNA-seq) libraries were generated in stallion tissues and compared to previously generated mare RNA-seq libraries to quantify variation in …

Management Of Late Summer Planted Annual Forages For Grazing And The Impacts Of Novel Sweet Bran Plus Products On Performance And Carcass Characteristics Of Beef Finishing Steers, Devin Anthony Jakub

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

Two separate grazing studies were conducted to evaluate: 1) the effects of rapeseed inclusion into late summer planted oats on the performance of growing steers during late fall and winter (Exp. 1) and 2) the effects of forage allocation on forage utilization and performance of steers grazing a late summer planted oat-rapeseed mix (Exp. 2). Variation in the corn wet milling process can result in negative effects on animal performance, nonetheless, there remains interest in further exploration and refinement of corn wet milling byproducts to achieve optimal byproduct compositions and cattle performance. Thus, another experiment was conducted to evaluate the …

Impact Of Wood-Sourced Biochar On Carbon And Nitrogen Capture In Beef Feedlot Systems, Jessica L. Sperber

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

A feedlot growing and finishing experiment evaluated the effect of including pine-sourced biochar at 0.8 (growing) and 1.0% (finishing) of dietary DM on steer performance, carcass characteristics, and greenhouse gas (GHG) production (Exp 1). Two nutrient mass balance experiments were conducted during winter and summer seasons to evaluate the effect of spreading unprocessed red cedar biochar on the feedlot pen surface on manure nutrient capture and cattle performance (Exp 2). In Exp. 1, the inclusion of biochar in the growing diet did not impact steer performance. The inclusion of biochar in the finishing diet significantly reduced intake and gain, resulting …

Evaluation Of Cattle Management For Systems With Limited Perennial Pasture, Morgan Grabau

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

Due to the conversion of perennial pasture and hay land to cropland in the western corn belt region, alternative methods of cow/calf management are being used to decrease reliance on perennial forages. These include grazing corn residue and feeding cow/calf pairs in confinement. Previous research has shown that limit-feeding a diet of low-quality forage and energy-dense co-products to cows in confinement is cost-effective. However, this strategy may limit the intake of the young calf and thus their performance. A study was conducted to evaluate the impacts of two alternative calf management strategies when pairs are in confinement, early weaning or …

Low-Oxygen Dry Aging Of Beef, Joseph A. Sonderman

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

The objective of this research project was to determine the effects of removing oxygen from the beef dry aging process. Boneless upper 2/3 Choice beef strip loins (n = 18) were randomly assigned to three aging treatments: wet aging, traditional (aerobic) dry aging, and low-oxygen dry aging. All treatments were aged for 41 days at 2 ± 1°C. The dry-aged treatments were held at 50% relative humidity (RH) with a fan speed of 2,200 revolutions per minute (RPM). Low-oxygen dry-aged samples were aged in chambers housed within an oxygen impermeable film bubble. After aging, yield was determined for the …

Enhancement Of Dry-Aged Beef Quality By Dietary Supplementation Of High Levels Of Vitamin E, David Manuel Velazco Marroquin

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

Crossbred cattle (n = 150; 10/pen) were grain-finished with the dietary addition of 2,200 international units of vitamin E (α-tocopherol) per head per day for 100 days. One low-Choice carcass (n = 12) was selected, and strip loins were collected. Low Choice control carcasses (n = 12) were randomly selected from commercial, fed-cattle production to serve as controls. Strip loins were randomly assigned to wet or dry aging for 42 days. On day 42, control dry-aged and control wet-aged loins had the highest TBARS values and vitamin E wet and dry-aged loins had lower TBARS values ( …

Evaluation Of Condensed Algal Residue Solubles As An Ingredient In Cattle Finishing Diets And Its Effects On Digestibility And Fatty Acid Flow And A Comparison Of Single And Dual Implant Strategies In Finishing Heifers, John Calvin Gibbons

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

Two experiments, a performance study (Exp. 1) and digestion study (Exp. 2) were conducted to evaluate a novel liquid feed, condensed algal residue solubles (CARS), in feedlot diets. In Exp. 1 and Exp. 2, steers were fed three inclusions of CARS at 0%, 2.5%, 5%. There were quadratic responses for greater carcass adjusted final BW, ADG, G:F, HCW, 12^th rib fat, and yield grade. There was a linear increase in marbling score and a linear decrease in DMI and LM area as CARS increased. In Exp. 2, CARS did not affect intake or digestibility. Fatty acid flow at the …

Evaluation Of Protein Sources And Holstein Finishing Systems For Organic Beef Production And A Comparison Of Single And Dual Implant Strategies In Finishing Heifers, Elizabeth A. Schumacher

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

Two in situ experiments were conducted to compare the rumen undegradable protein content (RUP) and RUP digestibility of conventional and organic field peas, fish meal, dehydrated alfalfa, and soybean meal. Significant differences were detected between feed samples in both studies for all variables measured. Variation existed between sample types but the data did not suggest that organic and conventional feeds are different when processed with the same methods. A performance experiment was conducted utilizing individually fed Holstein steers comparing the effect of RUP source in a simulated organic production system. Dietary treatments were: no supplemental protein (NONE), field peas (FP), …

Effects Of Late Gestation Supplementation And Creep Feeding On Spring Calving Beef Cows In The Nebraska Sandhills, Devin Lynn Broadhead

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

The objectives of this research were to 1) evaluate the effects of late gestation supplementation, synchronization and creep feeding on cow and calf production traits 2) evaluate the pooled effects of 5 studies involving late gestation supplementation on cow and calf traits. Experiment 1 was a three year study conducted on 8 pastures at the Gudmundsen Sandhills Laboratory. Cows were assigned to 1 of 4 late-gestation supplementation treatments, postpartum progestin or control, and 1 of 2 creep feed treatments to make up a 4 x 2 x 2 factorial arrangement. Calves were followed through to slaughter.

Experiment 2 involved 5 …

Beef Production Systems In The Nebraska Sandhills, Mckay Reed Erickson

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

Four studies were conducted to determine the effectiveness of improving production systems of beef cattle in the Sandhills region of Nebraska. These studies were to determine impacts of modified estrus synchronization protocols, genomic testing heifer calves for longevity, and evaluation of 2 differing calving systems (March or May) for improving biological outcome and improved production. Experiment 1 utilized 180 yearling heifers to determine the effectiveness of a second dose of prostaglandin F_2α(PGF) with those females not expressing estrus after an initial 14 d MGA-PG estrus synchronization protocol. The treatment of PGF did increase estrus expression, but did not …

Selective Harvest Methods And Chemical Treatment Of Baled Corn Residue For Utilization In Growing Calf And Dry Cow Diets, Ashley C. Conway

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

Three studies were conducted to evaluate baled corn residue using selective harvest method and anhydrous ammonia treatments to assess utility in growing calf and dry cow diets. Baled corn residue was harvested using conventional rake-and-bale (CONV) method, or harvested using the New Holland Cornrower in which either eight rows (8ROW), or two rows (2ROW) of corn stalks were chopped into the windrow with tailings. Bales were either not treated or ammoniated at 5.5% DM. When fed to wether lambs in a mixed ration (65% residue, 30% wet corn gluten feed) to determine digestibility, the 2ROW residue had greater apparent DM, …

Evaluation Of Growth Promoting Implant Strategies And Days On Feed On Finishing Heifer Performance And Evaluation Of Optimal Reimplant Times For Finishing Heifers And Steers, Caitlin A. Ohnoutka

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

Two experiments evaluated the effects of delayed, long-acting coated implants or uncoated implants to non-implanted heifers fed for constant or varying days on feed. In Exp. 1, heifers were implanted with either Revalor-XH on d 1, Revalor-200 on d 1, Revalor-XR on d 1, or Revalor-200 on d 70 compared to non-implanted control heifers when fed for an average of 198 d. In Exp. 2, heifers were implanted with Revalor-200 on d 1 and reimplanted with Revalor-200 on d 100, Revalor-XH on d 1, or not implanted and fed for different days on feed: 151, 165, 179, or 193. Implanting …

Impact Of Shade On Performance And Heat Stress Of Finishing Cattle And Pooled Analysis Of Individually Fed Finishing Trials, Brett A. Melton

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

A commercial feedyard trial in Eastern Nebraska evaluated the effect of shade vs no shade on cattle performance, ear temperature, and panting scores. No differences in overall performance (final BW, DMI, ADG, and G:F) or carcass characteristics (HCW, 12^th rib fat thickness, marbling, LM area, and calculated YG) were observed. Cattle that were provided shade had lower panting scores and ear temperatures, and greater DMI, compared to cattle that had no shade during heat events. Also, a treatment by hour interaction for movement of cattle occurred for one of the heat events. In comparison, the cool event had greater …

Identifying Breed Effects For Cow Mature Weight, Madeline J. Zimmermann

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

Mature weight (MWT) in beef cattle has increased over the past 30 yr. In general, larger cows are costlier to maintain than smaller cows, and their profitability depends on their production environment. A wide range of beef production environments exist in the United States. There are also a variety of beef cattle breeds that can be chosen and mated to create a type of cow which will be optimally suited to excel in a given environment. However, there remains a need for tools allowing effective comparison among breeds to facilitate such decision making. Unfortunately, estimated progeny differences ( …

Evaluation Of Alpha Amylase Containing Corn On Finishing Cattle Performance And Digestibility, Melissa L. Jolly-Breithaupt

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

One digestion and four finishing trials were conducted to evaluate the effect of a new corn hybrid containing an α-amylase trait, Syngenta Enogen Feed Corn (SYT-EFC) on site and extent of digestion, ruminal fermentation parameters, and feedlot performance. Experiments utilized corn containing the enzymatic gene compared to controls, the near isoline parental corn (NEG) or commercially available corn grain (CON), processed as dry-rolled corn (DRC) or high moisture corn (HMC) in diets with dry [distillers grains plus solubles (DGS)] or wet (Sweet Bran) milling byproducts. The corn grain of the experimental diets were fed as the sole grain source, comprising …

Corn Residue Grazing As A Component Of Semi-Confined Cow–Calf Production And The Effects Of Post-Weaning Management On Feedlot Performance, Shelby E. Gardine

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

Grazing corn residue can be a valuable alternative to harvested winter feed in a cow-calf production enterprise. The objectives of the first study were to: 1) determine the sample size needed to accurately estimate yield of corn grain and residue and 2) evaluate changes in residue quality throughout the fall/winter and spring-grazing seasons. Results suggest that 6-10 plants serve as a representative sample for grain yield while 7-10 plants are needed for a representative sample of residue yield. In vitro OM digestibility was greatest at the beginning of the fall and spring grazing seasons and declined over time (P < 0.01). In vitro …