Beef Science Commons^™

Improving Genomic Prediction For Feed Efficiency Traits In Beef Cattle Using Microbiome As An Intermediate Omics, Egodage Bhagya Sewwandi Samarakoon

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

Feed efficiency traits, including feed conversion ratio (FCR), average daily gain (ADG), and average daily dry matter intake (ADDMI), are economically important in beef cattle production. Emerging evidence suggests that host genetics influences feed efficiency traits through the microbiome. This study evaluates the integration of microbiome data as an intermediate layer in the Neural Network Mixed Model (NNMM), which hierarchically models genotype–microbiome–phenotype relationships as a unified regulatory network to improve genomic prediction accuracy. To reduce the computational burden of NNMM, microbiome features dimension were reduced using principal component analysis (PCA) and direct feature selection of top-ranked open reading frames (ORFs) …

The Detection Of Morbidity Using A Remote Sensing Ear Tag On Newly Received Steers And Feedlot Performance And The Effects Of Feeding Experior And Optaflexx On Carcass Characteristics And Meat Tenderness In Beef Steers, Lauryn O. Smidt

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

Two experiments were conducted to evaluate the effects of remote sensing health technology and growth-promoting feed additives on feedlot cattle performance, health outcomes, and carcass characteristics. In the first study, 638 crossbred steers (initial BW = 270 kg; SD = 18.6 kg) were used in a randomized block design to assess the effectiveness of a remote sensing ear tag (RST; HerdDogg, Seward, Nebraska) versus conventional pen-rider observation (PR) for detecting morbidity during a 35-d receiving period and subsequent 180-d finishing period. No differences were detected between PR and TAG for ending BW, average daily gain (ADG), dry matter intake (DMI), …

Carcass Mass And Cooling Dynamics As Determinants Of Beef Color, Tenderness, And Dark-Cutting Risk, Grace C. Johnson

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

Discoloration in beef has important implications to the beef industry. Dark-cutting (DC) beef remains one of the most economically significant color defects; however, industry prevalence has only marginally declined (≈ 0.1%) despite mitigation efforts. This lack of improvement largely stems from research focused on pre-harvest stress and glycogen depletion leading to dark, firm, and dry (DFD) beef. However, not all darkcutting beef originates from DFD phenotypes. Atypical dark-cutting (ATDC) phenotypes have recently been observed and do not exhibit the classic metabolic indicators of DFD. This trend coincides with steadily increasing carcass weights in the beef industry and raises the possibility …

Lipid Deposition In Beef Cattle, Kyra L. Elliott

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

Both the amount and types of lipid deposition in beef cattle are key determinants of carcass value and meat quality. Amounts of intramuscular, subcutaneous, and visceral fat influence carcass grading outcomes, palatability, and composition traits that are important to beef producers as well as consumers. The objectives of this thesis were to: 1) compare beef grading camera estimates of intramuscular fat to amounts of chemically extractable lipid, 2) characterize the lipidomes of beef intramuscular fat, subcutaneous fat, and lean muscle using shotgun lipidomics, and 3) identify and characterize a novel genetic variant in cattle that may have important implications for …

Evaluation Of Maternal Bovine Appeasing Substance Administration And Feed Access Time On Finishing Cattle Performance, Behavior, And Carcass Characteristics, Carsten L. Loseke

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

Novel products and bunk management techniques may significantly influence economically relevant performance metrics of feedlot cattle. The objective of the first experiment was to evaluate maternal Bovine Appeasing Substance (mBAS) administration on performance, carcass, health, and cortisol outcomes of yearling steers. Steers (n = 1,754, initial BW = 423 kg, SD = 25 kg) were received and assigned to pens for treatment allocation. Steers received either 10 mL of the mBAS or a mineral oil placebo at initial processing and reimplant. Hair samples were collected from a subset (n = 4 steers/pen) on d 0 and d 14. …

Application Of High-Pressure Processing To Improve The Color Of Dark Beef, Kara Ann Reynolds

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

Deviation of beef from the bright cherry-red color preferred by consumers is often discounted or discarded at retail, resulting in substantial annual economic loss to the beef industry. One such deviation is dark cutting beef, which is characterized by a darker lean appearance that is undesirable to consumers and often rejected. Similarly, beef from mature cattle tends to exhibit a darker surface color, which can also reduce consumer acceptability. High-Pressure processing (HPP) has been investigated as a strategy to improve the color of dark cutting beef. Previous studies have focused on identifying pressure levels and holding times that optimize color …

Honeybee Colony Response To Probiotic Supplementation And Grazing Practices, Katya M. Busenitz

Department of Entomology: Dissertations, Theses, and Student Research

Honeybee health is a complicated issue. Studies were conducted to scale honeybee (Apis mellifera) health from the microbiome to the landscape. Colony health parameters were measured in response to probiotic administration. Colony capped brood production, colony summer weight gain, and Varroa mite incidence were measured. I found that applications of over-the-counter probiotics did not improve the measured parameters of honeybee health compared to a control group. Results suggest that probiotic application was not beneficial but positive benefits may depend on application method, brand, or strain of probiotics used. I also examined how colony health metrics responded to different …

Evaluating Management Strategies And Technology To Improve Grazing Efficiency, Thomas E. Aquino

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

Increasing land costs and labor constraints continue to challenge beef producers. More intensive practices can increase harvest efficiency; however, many producers are deterred from implementing them due to increased labor and management considerations. Virtual fencing (VF) may provide a reduced labor alternative to traditional fencing for managing intensive grazing. This dissertation evaluated management strategies and VF technology to improve grazing efficiency of stocker cattle systems. In Experiment 1, VF was used to effectively manage groups of steers grazing in adjacent paddocks separated by only virtual boundaries. There was no difference in VF containment (99%) when steers were grazing co-fenced, with …

Evaluation Of Palm Oil As An Ingredient In Finishing Beef Cattle Diets On Performance, Carcass Characteristics, And Meat Quality, And The Composition Of Spayed Heifers To Intact Heifers Fed Melengestrol Acetate On Feedlot Performance And Carcass Characteristics, Tate S. Johnson

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

Heifers represent a large proportion of cattle placed in feedlots, making pregnancy management an important consideration for maintaining performance and carcass value. Melengestrol acetate (MGA) is commonly included in feedlot diets to suppress estrus and prevent pregnancy in intact heifers during the finishing period. Alternatively, spaying has historically been utilized as a management practice to allow heifers to graze alongside breeding cattle without the risk of pregnancy. Despite its historical use, there is limited contemporary research comparing the growth performance and carcass characteristics of spayed heifers with intact heifers managed with MGA under modern feedlot conditions. Therefore, a commercial study …

Exploratory Evaluation Of Handler Performance And Processing-Related Outcomes During Cattle Handling, Morgan Marquardt

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

Animals have several critical roles in society, including the production of food and fiber, and companionship. Contact with animals has been shown to benefit human physical and mental health, yet little research has investigated the impact that humans have on animals. Handler skill may considerably affect the extent to which humans influence animal health and wellbeing, and this may be a critical consideration for animal agriculture. Objective assessment of cattle handler skill has received limited attention in the scientific literature, despite its importance to human safety and animal welfare. When compared to less skilled handlers, highly skilled cattle handlers may …

Evaluating Cow/Calf And Stocker Performance When Grazing Sudangrass With And Without Sunnhemp, Shelby L. Davis-Jenkins, Daren D. Redfearn, Mary E. Drewnoski

Nebraska Beef Cattle Reports

Summary with Implications

Sudangrass can provide high-quality summer forage, supporting cow/calf pairs and growing cattle. In this study, sudangrass or a sudangrass–sunnhemp mix was grazed over two years by cow/calf pairs and heavy stockers (~880 lb). There was no difference in carrying capacity between forage types. Sunnhemp inclusion had no effect on cow body condition or nursing calf gain. Cows maintained condition through peak lactation, and nursing calves gained 2.27 lb/day. Stockers gained 1.56 lb/day on sudangrass alone and 1.73 lb/day on the mix. However, the added seed cost of sunnhemp increased the cost of gain in year 1 and …

Effect Of Corn Harvest With A Chopping Head On Performance Of Cattle Grazing Corn Residue, Conner K. Biehler, Mary E. Drewnoski, Jim C. Macdonald

Nebraska Beef Cattle Reports

Summary with Implications

The effects of harvesting corn using a chopping vs a standard, non-chopping combine head on steer performance when grazing corn residue were evaluated. Steers were supplemented with dry distillers grains at 0.6% of initial body weight. The amount of corn residue mass and the quality of the husk did not differ between harvest methods. Steer gains were over twice as high in year 2 (2.10 lb/d) than year 1 (0.76 lb/d), potentially due to greater husk digestibility and milder winter conditions. Corn residue harvested with a standard combine head resulted in a slightly higher average daily gain …

Artificial Insemination Of Beef Heifers With Multi-Sire Semen, Dempster M. Christenson, Jordan M. Thomas, Daniel J. Kelly, Rick N. Funston

Nebraska Beef Cattle Reports

Summary with Implications

This study compared pregnancy rates of beef heifers artificially inseminated with multi-sire semen to single-sire semen. It was hypothesized pregnancy rates resulting from multi-sire semen would be increased compared to single-sire semen. Heifers were artificially inseminated with semen from one of three sires or semen from a combination of the same three sires. Pregnancy rates did not significantly differ. Paternity testing suggests sire parentage can be unequal when semen is mixed from multiple sires. In summary, similar pregnancy rates were observed using single-sire and multi-sire semen, but progeny may have unequal sire representation.

Supplementing Monensin And Rumen Undegradable Protein To Late-Gestation Heifers, Dempster M. Christenson, Rick N. Funston

Nebraska Beef Cattle Reports

Summary with Implications

This study evaluates the effects of supplementing late-gestation heifers with rumen-undegradable protein and monensin on weight gain, feed efficiency, and reproductive performance, and subsequent impact on progeny. We hypothesized that supplementation would enhance growth and feed efficiency, ultimately improving cow and calf performance. Previously synchronized artificially inseminated heifers were fed ad libitum hay for 89 d prior to calving. Feed was top dressed with chelated mineral with or without monensin, dried distillers’ grains, or dried distillers’ grains and monensin. Supplementation with rumen undegradable protein increased growth rate and decreased calving difficulty with no further effects on cow …

Effect Of Feeding Whole Soybeans, Roasted Soybeans, Or Distillers Grains In Silage-Based Growing Beef Diets, Melissa K. Bausch, Rebecca Mcdermott, Jim C. Macdonald, Pablo L. Loza, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

An individual feeding experiment was conducted to evaluate the effect of feeding raw whole soybeans (WSB), roasted whole (RSB) soybeans or distillers grains (MDGS) at three inclusions (7%, 14%, or 21% of diet dry matter) on growing performance, compared to a common control diet (0%) with urea. The greater inclusions of roasted soybeans or distillers grains increased gain and efficiency in growing cattle. Cattle fed the 21% inclusion of roasted soybeans were the most efficient, likely due to the protected protein increasing rumen undegradable protein content, and the additional energy from the higher levels of fat and …

Live Biomass Estimation With Canopeo In Rangeland Systems, Hannah K. Allen, Mitchell B. Stephenson, Daniel R. Uden

Nebraska Beef Cattle Reports

Summary with Implications

This project evaluated Canopeo, a free smartphone app that estimates fractional green canopy cover (FGCC), as a tool for monitoring aboveground biomass in Nebraska Sandhills rangelands. Live biomass was significantly higher in August than in June with some variability by year. FGCC showed a moderately strong relationship with current-year live biomass collected in either June or August. These results indicate that, in addition to producers’ field knowledge, Canopeo images taken with a smartphone or digital camera can offer a quick, visual estimate of forage conditions. This method may help reduce the need for labor intensive and destructive …

Effect Of An Accelerated Adaptation Protocol On Performance And Health Of Feedlot Steers Drenched With Lactipro, Rebecca L. Mcdermott, Samuel E. Loy, Isaque F. Vicci, Mark Corrigan, Braden C. Troyer, Galen E. Erickson, Jim C. Macdonald

Nebraska Beef Cattle Reports

Summary with Implications

A finishing study evaluated the effects of an accelerated adaptation protocol in conjunction with Lactipro on performance and health of steers. Five adaptation programs were evaluated with steers adapted to a finishing diet in 21, 14, 7, or 0 days. An additional accelerated adaptation program provided intensive feed delivery with 0-d adaptation. Cattle assigned to the 21-d and 0-d adaptations gained faster and consequently had greater HCW compared to the 7-d and 14-d adaptation, resulting in a quadratic response for ADG and HCW. The 0-d adaptation with intensive feed delivery had similar ADG and HCW compared to …

Energy Value Of High-Moisture Corn In Feedlot Cattle Diets Derived Through Meta-Analysis, Alfredo Dicostanzo

Nebraska Beef Cattle Reports

Summary with Implications

Cattle feeders or their nutritionists who rely on high-moisture corn (HMC) use a standard adjustment to energy content of the diet based on observation or previous research reports. Because moisture content of HMC is the result of many field and harvest factors, a common adjustment to the energy value of HMC applied to all conditions may not be appropriate. The hypothesis that moisture content of HMC determines its energy concentration was tested. Through a meta-analysis, it was determined that feed intake was depressed while energy content of HMC increased at greater moisture content. A simple method to …

Effects Of Feeding Raw Soybeans Or Roasted Soybeans To Feedlot Steers, Melissa K. Bausch, Jim C. Macdonald, Pablo L. Loza, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

A feedlot study compared feeding raw or roasted soybeans, soybean meal, or distillers grains to a dry-rolled corn with urea control on finishing cattle performance and carcass traits. Cattle fed roasted soybeans had improved marbling and gained more weight over the feeding period than cattle fed whole soybeans. Feed conversion was improved in the steers fed the roasted and whole soybean containing diets over steers that consumed the distillers grains diet. Cattle fed soybean meal and distillers grains had similar performance and carcass characteristics in this experiment. Cattle fed soybeans, soybean meal, or distillers had better gains …

Effect Of Using Either Synovex Primer Or Synovex Choice Compared To Not Implanting On The Performance Of Growing Steers, Sawyer D. Starrett, Rebecca L. Mcdermott, Sofia Suarez Lorences, Pedro Henrique Jota Fernandes, Dirk Burken, Jessica L. Sperber, Galen E. Erickson, Jim C. Macdonald

Nebraska Beef Cattle Reports

Summary with Implications

A 120-day winter-growing study utilized 576 head of steers to evaluate three dry lot implant strategies on the growth of steers. The three implanting strategies included a non-implanted control, Synovex® Primer™, or Synovex Choice®. While on harvested corn residue fields, steers were supplemented with 4 lb Sweet Bran and 0.375 lb of a vitamin and mineral package. The targeted gain for the non-implanted control was 1.25 lb/d. Both Synovex Primer and Synovex Choice increased ADG over the non-implanted control cattle by 7.5% and 12.7%, respectively. Additionally, Synovex Choice had a 4.8% increase in ADG over Synovex Primer. …

Evaluation Of Ferappease Administered At Arrival And Time Of Reimplant On Feedlot Performance And Carcass Characteristics Of Yearling Beef Steers, Carsten L. Loseke, Galen E. Erickson, Jessica L. Sperber

Nebraska Beef Cattle Reports

Summary with Implications

Cattle experience stress in the feedlot during handling events such as initial processing and reimplant that can negatively impact morbidity and mortality, feedlot performance, and carcass outcomes. Application of a maternal Bovine Appeasing Substance (mBAS) marketed as FerAppease (FERA Diagnostics and Biologicals) has been hypothesized to mitigate stress in cattle. A commercial feedlot study compared the effectiveness of FerAppease applied in 10mL doses to yearling native beef steers at initial processing and reimplant to a placebo product on cattle performance, morbidity and mortality parameters, and carcass traits. Steers administered FerAppease tended to have improved feed conversion on …

Effect Of Feed Access Time On Feedlot Cattle Performance, Carcass Characteristics, Feeding Behavior And Ruminal Ph, Carsten L. Loseke, Rebecca L. Mcdermott, Josh R. Benton, Keara O'Reilly, Galen E. C. Erickson, Jim C. Macdonald

Nebraska Beef Cattle Reports

Summary with Implications

Bunk management is crucial for modern feedlots, and understanding the ideal time to target a slick bunk is important. A feedlot study compared the effect of providing finishing cattle with 12, 15, 18, 21, or 24 hours of access to feed on performance, carcass characteristics, feeding behavior, and ruminal pH. As access time to feed increased, feed intake and day-to-day variation of feed intake increased linearly, while gain and feed conversion were unchanged. Cattle with greater access time to feed spent more time per day at the bunk, and consumed feed more slowly. A cubic effect on …

Evaluation Of Lysoforte Extend On Rumen Fermentation Parameters, Rumen And Total Tract Digestion, And Fatty Acid Digestion, Anna Kobza, Dalton Anderson, Jerilyn Hergenreder, Jim C. Macdonald

Nebraska Beef Cattle Reports

Summary with Implications

Supplemental fat fed in finishing diets in recent years has generally increased in price. This digestibility study evaluated LYSOFORTE Extend, a lysophospholipid based nutritional emulsifier, in beef finishing diets containing tallow or corn oil. Five ruminally and duodenally cannulated steers were used in a 5 × 5 Latin Square design. Treatments followed a 2 × 2 +1 factorial: 1) No Oil (negative control), 2) Corn Oil (3.5%), 3) Tallow (3.5%), 4) Corn Oil + LFE (8 g/d), and 5) Tallow + LFE (8 g/d). Cattle fed the negative control diet had greater dry matter intake than cattle …

Evaluation Of Renergy On Finishing Steer Growth Performance, Carcass Traits, And Liver Abscess Prevalence And Severity, Sofia Suarez Lorences, Jeff Heldt, Pablo L. Loza, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

A feedlot study evaluated the effects of Renergy™ (Selko USA) and Rumensin® (Elanco Animal Health) on growth performance, carcass traits, and liver abscess severity in finishing beef cattle. Using a 2 × 2 factorial design, cattle were fed one of four diets: control (no additive), Renergy, Rumensin, or both additives combined. A significant interaction between Renergy and Rumensin was observed for feed conversion, with a tendency for interaction in dry matter intake (DMI). Cattle fed Renergy tended to have lower DMI and lower average daily gain, though DMI did not differ between cattle fed both additives and …

Evaluation Of Enteric Methane From Cattle Adapted Using Ramp Vs. A Traditional Forage Program Stepped Up To Different Finishing Diets, Jack T. Fort, Isaque F. Vicci, Josh R. Benton, Rebecca L. Mcdermott, Jim C. Macdonald, Maggie E. Youngers, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

A 93-day finishing experiment evaluated feeding RAMP (Cargill Corn Milling, Blair NE) during diet adaptation and finishing diet containing 20% Sweet Bran compared to a traditional adaptation program using forage with a finishing diet without Sweet Bran on methane and carbon dioxide production, animal performance and carcass characteristics in beef steers. Cattle were measured using a calorimetry emission barn to quantify the production of methane and carbon dioxide during step 1 of adaptation and 1 time during finishing diet. Feeding RAMP did not significantly reduce methane but did reduce the ratio of methane to carbon dioxide during …

Evaluation Of Enteric Methane From Cattle Adapted To The Same Finishing Diet Using Ramp Versus Forage, Jack T. Fort, Isaque F. Vicci, Josh R. Benton, Rebecca L. Mcdermott, Jim C. Macdonald, Maggie E. Youngers, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

A 139-day finishing experiment evaluating the effects of feeding RAMP (Cargill Corn Milling, Blair NE) during diet adaptation compared to a traditional forage program on methane and carbon dioxide emissions was done to corroborate a previous study (2025 Nebraska Beef Report, pp. 55-58). Cattle were measured using a calorimetry emission barn to quantify the production of methane and carbon dioxide during step 1 of adaptation and 1 time during a common finishing diet. Feeding RAMP had no statistical reduction in methane or carbon dioxide production during step 1. When cattle were fed the same finishing …

Health Indicators Worsened By Moderate-Intensity Heat Stress Are Only Partially Recovered By Ω-3 Polyunsaturated Fatty Acid Supplementation, Melanie R. White, Shelley A. Curry, Ashley A. Hahn, Jessica L. Petersen, Ty B. Schmidt, Dustin T. Yates

Nebraska Beef Cattle Reports

Summary with Implications

Heat stress throughout the summer and into the fall is a persistent hurdle for growing and finishing cattle in Nebraska. Minimizing the impact of heat on growth and well-being of cattle is critical to the productivity and profitability of beef production. This project aimed to evaluate the effect of an anti-inflammatory dietary supplement, ω-3 polyunsaturated fatty acids (ω-3 PUFA), on physiological indicators of stress during a 4-day moderate-intensity heat challenge. Heat stress elevated core body temperature and respiration rates as expected but did not impact circulating inflammatory biomarkers. Heart rate variability measurements indicative of adrenergic stress and …

Modulation Of Heat Stress Responses In Cattle Supplemented With Dietary Ω-3 Polyunsaturated Fatty Acids, Shelley A. Curry, Melanie R. White, Ashley A. Hahn, Dustin T. Yates

Nebraska Beef Cattle Reports

Summary with Implications

Heat stress in beef cattle triggers physiological and metabolic disturbances that compromise performance, health, and welfare. In this study, Red Angus heifers exposed to heat stress for 5 days exhibited elevated body temperatures, increased heart and respiration rates, and altered hematological and acid–base parameters. A commercial ω-3 polyunsaturated fatty acid (PUFA) dietary supplement failed to improve heat stress-reduced ribeye area or red blood cell parameters but did resolve the reduction in blood chloride concentrations, which is consistent with restoration of electrolyte balance and hydration under heat stressed conditions. These results indicate that ω-3 PUFA supplementation offers some …

Impact Of Storage And Cooking Temperature On Listeria Innocua Growth In Plant-Based And Beef Proteins, Esther Vanoverbeke, Oliver Munezero, Gary A. Sullivan, Samodha C. Fernando

Nebraska Beef Cattle Reports

Summary with Implications

Listeriosis, caused by Listeria monocytogenes and other Listeria spp., is a food-borne illness, that accounts for 260 deaths annually. The objective of this study was to identify how storage method and cooking temperature impacts Listeria innocua growth in ground beef and plant-based protein patties. Patties (162 ground beef; 162 plant-based) were used in 3 replications. For each replication, patties were either inoculated (1×108 CFU) or not inoculated and stored for 26 hr at refrigeration, freezer, or room temperature. Three patties per storage method were cooked to either 145°F or 165°F and were plated before/after cooking. Nine patties …

Inclusion Of Palm Oil Products In Finishing Diets On Ground Beef Quality And Retail Stability, Anna Kobza, Galen E. Erickson, Jim C. Macdonald, Mitch L. Norman, Josh R. Benton, Rebecca L. Mcdermott, Long Zou, Kyra L. Elliott, Anna G. Hilton, Chad A. Russell, Jessie C. Morrill

Nebraska Beef Cattle Reports

Summary with Implications

Rising costs and availability of supplemental fats have increased interest in alternative fat sources in feedlot finishing diets, including palm oils. This experiment evaluated how refined, bleached, and deodorized (RBD) palm oil products included in the diet of feedlot finishing steers affect beef fat color and ground beef shelf-life. Steers were fed diets with no supplemental fat (No Oil), corn oil (Corn Oil), whole palm (Whole Palm), palm stearin (Stearin), or palm olein (Olein) at 4% dietary DM. Subcutaneous fat from cattle fed corn oil was more yellow than that from No Oil or palm oils. Ground …