Digital Commons Network^™

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 …

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 …

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 …

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 …

2026 Nebraska Beef Cattle Report

Nebraska Beef Cattle Reports

The 2026 Nebraska Beef Cattle Report brings together applied research, emerging technologies, and management insights that directly address the evolving challenges and opportunities facing today’s beef industry. This year’s collection includes 36 articles that span the full beef production system, from cow/calf and forage management to feedlot nutrition, animal health, behavior, meat quality, and sustainability, providing science-based guidance grounded in real-world production contexts.

Cow/Calf Nutrition, Reproduction, and Management

This section highlights management strategies that influence reproductive success and long-term herd performance. Articles focus on late-gestation heifer nutrition and practical applications of artificial insemination to support efficient, productive cow/calf systems.

Forage, …

Vegetation Species And Bed Position May Drive Epifaunal But Not Nekton Habitat Use In Estuarine Submerged Vegetation In The Mobile-Tensaw River Delta, Alabama, Steven Vroljik, Kathryn O'Shaughnessy, Ashley Mcdonald, Zoey Hendrickson, Bethany Kiley, Anna Reimer, Sierra Robertson, Samantha Smith, Edward Sullivan, Charles Martin

Gulf and Caribbean Research

Submerged aquatic vegetation (SAV) supports nekton and epifaunal macroinvertebrates, sustaining food webs and ecosystem services in estuaries. Invasive SAV can alter these dynamics by displacing native vegetation and restructuring communities. In Alabama’s Mobile-Tensaw Delta (MTD), Eurasian milfoil (Myriophyllum spicatum) is rapidly expanding and outcompeting native wild celery (Vallisneria americana). This study compared nekton and epifaunal assemblages between M. spicatum and V. americana, focusing on edge versus interior positions. Nekton surveys identified 22 taxa (M. spicatum, n = 13; V. americana, n = 18), but assemblages did not differ significantly between vegetation types …

Design And Fabrication Of A Scaled Automated Dairy Farm Model: A Report, Md Towfiqur Rahman

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Summary

This study investigates how ventilation systems work in dairy barns and builds a scaled model to support education and research. The project is designed to help students from the University of Nebraska–Lincoln (UNL), K-12 learners, and researchers in animal science, veterinary medicine, and engineering gain visual experience with dairy facility components and processes. Different ventilation methods were studied, leading to the design of a 1/64-scale tunnel-ventilated dairy barn meant for 60 Holstein Friesian cows. Barn dimensions were set based on real Holstein cow measurements to ensure proper cow comfort, while airflow requirements were calculated and scaled down. Miniature fans …

Fecal Microbiota Transplantation Modulates Gut Microbiota And Lipid Metabolism To Reduce Diarrhea In Low-Birth-Weight Neonatal Calves, Zhanhe Zhang, Duo You, Donglin Wu, Xintong Li, Yang Jia, David L. Harmon, Ming Xu

Animal and Food Sciences Faculty Publications

This study aimed to elucidate the mechanism by which colonic fecal microbiota transplantation (FMT) improves lipid metabolism in low-birth-weight neonatal calves via modulation of the gut microbial ecosystem. In a completely randomized design, seventy newborn Holstein calves (1 day old, 32.63 ± 3.13 kg BW) were assigned to two groups (35 calves/treatment; 30 females and 5 males per group). A healthy calf was used as a fecal donor. A 10% fecal bacterial suspension was prepared and administered colonically (50 mL, twice daily for 5 days). All calves were fed the same milk replacer and weaned using a step-down protocol at …

Wet Aging And Internal Endpoint Cooking Temperature Influence Color Of Lamb Longissimus Lumborum Muscle, Oluwatobi M. Ogunsola

Theses and Dissertations--Animal and Food Sciences

Color is a critical quality attribute that influences consumer purchase decisions for fresh and cooked lamb and is governed by myoglobin's redox chemistry. Wet aging is commonly used to enhance lamb tenderness, while endpoint cooking temperature is the primary determinant of internal cooked color. However, the combined effects of these factors on the color stability of the lamb longissimus lumborum (LL) muscle during refrigerated storage remain unclear. The objective of this thesis was to evaluate the effect of wet aging duration on the color attributes and lipid oxidation of fresh lamb LL chops and endpoint cooking temperature and refrigerated storage …

Crab And Lobster Shell Meal Taste Preferences Of Dairy Heifer Calves, Summer R. Pescinski, Peter S. Erickson

Honors Theses and Capstones

Objective: This preference study was conducted to evaluate the palatability of crab shell meal (CM) and lobster shell meal (LM) when added to calf starter for post-weaned dairy heifer calves.

Materials and methods: Six calves were used for a sequential elimination experiment to rank their taste preferences when offered control calf starter, calf starter mixed with 50 g of CM, and calf starter mixed with 50 g of LM.  The calves were kept on the study for a total of 5-d split into two feeding segments.  Preference was determined by calculating the total intake of each treatment …

Metabarcoding Ixodes Scapularis To Characterize Feeding Behavior In Comparison To Pathogen Carriage And Geospatial Distribution, Adrianna Kate George

Honors Theses and Capstones

No abstract provided.

Effects Of Perching Behavior In Broilers On Welfare And Production Benefits, Natalie G. Bunn

Honors Theses and Capstones

Broiler chickens are bred for feed efficiency, rapid growth rate, and muscle development. Conventional broiler farms utilize fast-growing breeds that reach market weight rapidly and present welfare concerns. Primarily raised indoors with little enrichment, the genetics and husbandry practices of broilers encourage inactivity and perpetuate health problems such as skeletal deformities, lameness, and pododermatitis. Despite the commonness of these issues, there is little research on the reduction of such health complications through production management. This study investigated methods to promote perching behavior and the effects of riser perch and platform perch utilization in broilers. A mixed flock of slow-growing Gray …

Exploring The Association Between Internal Body Temperature And Metabolic Status In Early Lactation Jersey Cattle, Alexandra Ferreri, Claira Seely

Honors Theses and Capstones

No abstract provided.

An Integrated Evaluation Of Trace Mineral Status, Regional Variation, And Supplementation Effects On Circulating Mineral And Reproductive Performance In American Plains Bison, Bailey M. Rodriguez

Electronic Theses and Dissertations

The continued expansion of the American Plains Bison (Bison bison) industry has increased the need for science-based nutritional recommendations tailored specifically to the species, due to limited species-specific research. Because trace minerals influence immune function, growth, and reproductive performance, establishing baseline mineral status and evaluating responses to supplementation are critical for advancing bison production and conservation efforts. This thesis integrates two complementary investigations to evaluate trace mineral status in American Plains bison at both regional and herd management levels. First, a herd level comparison evaluated the influence of differing mineral supplementation strategies on circulating mineral concentrations, herd performance, and reproductive …

Winter-Feeding High Forage Vs. High Concentrate Diets To Beef Cows: Effects On Placental Transcriptomics, Lactation Capacity, And Enteric Methane Emissions, Megan Ann Wehrbein

Electronic Theses and Dissertations

Nutritional management and lactation performance are critical factors influencing productivity in cattle. This research includes two complementary studies. The first study was a meta-analysis to develop a lactation curve for Bos taurus cattle in North America using data from machine or hand milked cows. Data from 7 studies were used resulting in 1340 cow-day observations. Milk yield was analyzed by parity (primiparous or multiparous) and feeding management (non-nutrient restricted or nutrient restricted), revealing that primiparous cattle peaked earlier and at lower yields than multiparous cattle, and nutrient restriction reduced peak milk yield. Overall, Bos taurus cattle followed lactation trends similar …

Managing Dietary Nonstructural Carbohydrates In Insulin Dysregulated Horses: Pasture, Long-Stem Forage, And Restrictive Grazing Strategies, Morgan J. Askins

Theses and Dissertations--Veterinary Science

Insulin dysregulation (ID) is a complex endocrine disorder, impacting a large percentage of the equine population. ID is the defining characteristic of equine metabolic syndrome (EMS). Within the various classifications of EMS horses, the commonality is ID and their higher risk of laminitis. To mitigate insulin response and laminitis risk in ID horses, current management focuses on restricting pasture exposure and feeding low nonstructural carbohydrate (NSC) rations. Minimal studies have evaluated how ID horses respond to pasture of various NSC, long-stem forages, and restrictive grazing strategies. Providing horse owners and managers with improved nutritional management recommendations for ID horses with …

Between The Rails: Experiential Education And Its Impact On Compliance And Consistency In Racetrack Surface Management, Heather Mackenzie

Theses and Dissertations--Community & Leadership Development

Recent regulatory requirements within the Thoroughbred racing industry have increased expectations for consistent collection and reporting of racetrack surface data. Despite clear standards, implementation in daily operations remains inconsistent, highlighting a gap between regulation, knowledge, and practice. This study examined the impact of an experiential education curriculum on racetrack personnel’s self-efficacy and reporting consistency.

Using a quantitative design, data were collected through pre- and post-surveys measuring self-efficacy and records of the number of days surface data were entered. Descriptive statistics, paired-samples t-tests, and effect size analyses were used. Results showed a statistically significant increase in self-efficacy (p < .001) with large effect sizes, indicating meaningful gains in confidence and comfortability. Reporting consistency did not show a statistically significant change (p = .885).

Overall, experiential education …

Retention Time Of Microplastics In The Purple Sea Urchin (Arbacia Punctulata), Alexandra Shore

Honors Theses and Capstones

Marine ecosystems around the world are facing the problem of plastic pollution. Large pieces of plastic eventually degrade into smaller microplastics that are suspended in the water column and sink to the seabed. Sea urchins are exposed to microplastics as they graze on the sea floor and can accidentally consume these pollutants. Sea urchins are ecologically important animals because they physically alter their ecosystem via grazing and are integral part of marine food webs. To better understand how sea urchins interact with microplastics, purple sea urchins were exposed to microfibers and microspheres in a laboratory setting, and the retention time …

Growing South Dakota (Winter 2026), College Of Agriculture, Food And Environmental Sciences

Growing South Dakota (Publication of the College of Agriculture, Food and Environmental Sciences)

[Page] 2 International Year of Rangelands and Pastoralists: South Dakota rangelands take center stage
[Page] 4 The professor and the soil
[Page] 8 Range ready: Helping students bridge the gap between conservation and agriculture
[Page] 9 Resilient rangelands: Native Plant Initiative’s role in reviving South Dakota’s prairies
[Page] 10 Jackrabbits lead the charge in bison research and education
[Page] 12 Agricultural and biosystems engineering celebrates century of education
[Page] 16 SDSU Quarter Scale Tractor Club: An impact beyond awards
[Page] 18 Building a legacy of opportunity: Karen D. Stuck Endowment strengthens agricultural communication program at South Dakota State University
[Page] …

Effects Of Particle Size Difference In Two Different Sweet Bran Products On Total Tract Digestibility And Rumen Ph, Emily K. Hoefling, Anna Kobza, Jessica L. Miller, Maggie E. Youngers, Galen E. Erickson, Jim C. Macdonald

Nebraska Beef Cattle Reports

Summary with Implications

Seven ruminally fistulated heifers were utilized in a 6 x 7 row-column design to evaluate two different Sweet Bran particle size products (1.8 or 2.5 mm) included at 13%, 18%, or 23% of the diet (DM) on total tract digestibility and rumen fermentation parameters. The treatment design was a 2 x 3 factorial. Rumen pH was reduced and organic matter digestibility tended to be reduced with the small particle size when Sweet Bran was included at 13% of the diet. Both NDF digestibility and dietary digestible energy concentration tended to improve with the larger particle size. The …

Use Of Virtual Fences To Co-Fence Two Groups Of Cattle With Adjacent Virtual Boundaries, Thomas E. Aquino, Mary E. Drewnoski, Biquan Zhao, Pedro Henrique Jota Fernandes, Isaque F. Vicci, Mitchell B. Stephenson, Yijie Xiong

Nebraska Beef Cattle Reports

Summary with Implications

While virtual fencing (VF) has proven effective in managing cattle, limited data exist on using it to manage two separate groups of cattle within the same area. If successful, this approach could reduce infrastructure costs and increase management flexibility. In this trial, VF-trained steers (n = 39) were placed in pastures with either no neighboring cattle (isolated) or next to a separate group with only a VF boundary between them (co-fenced). Containment exceeded 99% across all cattle, demonstrating that VF creates effective boundaries regardless of fence treatment. There was no statistical difference in the number of audio …

Defining The Parameters Of High-Pressure Processing To Improve The Quality Of Dark-Cutting Beef, Ashley A. Hahn, Leila G. Venzor, Shelley A. Curry, Grace C. Johnson, Mary-Grace C. Danao, Ranjith Ramanathan, Jordan C. Wicks, Gary A. Sullivan

Nebraska Beef Cattle Reports

Summary with Implications

Dark-cutting beef is a result of preharvest stress and devalues the resulting carcass. High-pressure processing (HPP) has been recently identified as a potential strategy to improve the undesirable appearance of dark-cutting beef. Dark-cutting beef strip loins were collected from a local processing facility, sectioned, and assigned an HPP pressure (300 or 450 MPa) and holding time (0, 1, 30, 60, or 90 s). Overall, HPP increased the lightness and redness of dark-cutting beef, particularly the longer the pressure was held at both pressure levels. Additionally, negative effects such as increased meat discoloration, decreased tenderness, and increased rancidity …

Evaluating Sorghum X Sudangrass Seed Digestibility, Evan Blank, Thomas E. Aquino, Mary E. Drewnoski

Nebraska Beef Cattle Reports

Summary with Implications

A sorghum-sudangrass hybrid was swathed in the hard dough stage and grazed by growing steers from November 2023 to January 2024. Steers appeared to select the seedheads when grazing. The seed made up approximately 12.6% of swathed forage mass, but its energy contribution appears limited due to poor digestibility. When incubated whole, only 23% of dry matter and 13% of starch was digestible. Grinding improved digestibility but still left 40% of the dry matter and over 85% of starch unavailable. Weathering over two months did not improve digestibility, indicating the seed coat remains intact through winter. Compared …

Long-Term Trends Of Annual Herbaceous Expansion In The Nebraska Panhandle: Rangeland Analysis Platform Data, Karley Dieckmann, Mitchell B. Stephenson, Miranda Mueller

Nebraska Beef Cattle Reports

Summary with Implications

This descriptive analysis evaluated changes in Annual Forb and Grass (AFG) herbaceous cover in the Nebraska Panhandle from 1986 to 2023 using the Rangeland Analysis Platform (RAP). It was hypothesized that AFG herbaceous cover would show an increasing trend over time, indicating the potential expansion of the annual invasive cheatgrass (Bromus tectorum). County-level RAP data were used to calculate long-term means as an indicator. Results showed an increase in AFG cover across the region. Trends were cyclical, with cover peaking and dipping over time, but the overall trajectory showed increases in AFG in the Panhandle. The increasing …

Multi-Omics Analysis Of Immune-Metabolic Adaptation To Direct-Fed Microbial Supplementation In Newly Weaned Beef Steers, Adekunle Odunayo Ajiboye

Graduate Theses, Dissertations, and Problem Reports (ETD)

Immune and metabolic disruption during weaning represents a major challenge to health and productivity in beef cattle. This dissertation tested the hypothesis that supplementation with multi-strain direct-fed microbials (DFMs) modulates immune regulation and metabolic pathways associated with adaptation to weaning stress. To address this, whole-blood transcriptomics and plasma metabolomics were used to evaluate molecular and metabolic responses in newly weaned beef steers during the receiving period. Transcriptomic analysis identified differential expressions of genes associated with immune signaling and inflammatory regulation, indicating modulation of immune-related pathways without changes in growth performance. Metabolomic analysis revealed alterations in circulating metabolites related to amino …

The Depuration Of Microplastic Pollution In Aquacultured Indian River Lagoon Oysters, Lee Nguyen

Honors Undergraduate Theses

Plastics are widely used in consumer goods and industrial manufacturing, and their degradation into microplastics (MP, size < 5 mm) has created an emergent environmental pollutant. Plastics readily enter aquatic environments, where they accumulate additional contaminants and bioaccumulate in organisms. While MP contamination in marine ecosystems is well documented, less is known about MP presence in aquacultured shellfish. Depuration, the process of purging contaminants from shellfish, is conducted in sterile seawater without food, which may cause oyster starvation and death. To date, MP depuration has not been examined in the aquacultured eastern oyster (Crassostrea virginica) in published studies. This study had 3 goals: 1) evaluate the effects of algal feed on oyster survival during depuration, 2) determine the effect of algal feed on depuration effectiveness, and 3) investigate the effect of a ten-day depuration on MP concentration in aquacultured C. virginica soft tissue. MP were quantified in oyster tissues, biodeposits, and in industrial algal feed. Tissues were digested using alkaline solutions, manually examined via microscopy, and analyzed using Fourier-Transform Infrared Spectroscopy (FTIR) to investigate MP polymer …

Evaluating The Use Of Precision Technology To Understand Differences Between Ketotic And Non-Ketotic Jersey Cows, Emily Kathryn Palermo

Honors Theses and Capstones

No abstract provided.

Indirect Effects Of Coral Bleaching On Tursiops Truncatus Diet And Foraging Behavior In Bocas Del Toro, Panama, Annabel Fiero

Scripps Senior Theses

Indirect effects, where another species or factor mediates the effects of a given species, are critical to ecosystem structure and resilience. Shifts in fish community structure, as a result of rapidly declining coral reefs in the Caribbean due to warming-induced bleaching, pose a threat to apex predators like Tursiops truncatus (bottlenose dolphins). Branching corals create habitat niches for numerous fish species. These fish rely on coral for food and habitat, and in turn provide food for upper trophic levels. Prior research has highlighted how coral bleaching will disrupt Acroporid reef building corals and fish community structure, but the effects of …

Measuring The Rise And Fall Of Plasma 25-Hydroxyvitamin D Concentrations In Blue-Tongued Skinks (Tiliqua Scincoides) Following Ultraviolet B Exposure And Withdrawal, Ashleigh Godke, Haerin Rhim, M. Graciela Aguilar, Keishla Marrero-Acosta, Mark Mitchell

Distinguished Undergraduate Researcher Program

Species-specific husbandry guidelines remain limited for blue-tongued skinks (Tiliqua scincoides), especially in relation to ultraviolet B (UVB) lighting and vitamin D requirements. This study aimed to determine whether UVB exposure is necessary for these skinks and how long 25-hydroxyvitamin D (25-OHD) concentrations persist after UVB withdrawal. Eleven adult skinks who had been fed with wet cat food were exposed to 12 or 2 h of UVB per day for four weeks. Plasma 25-OHD concentrations were very low at the baseline, and significantly increased post-UVB in both groups (p < 0.01), with the 12-hour group increasing from baseline concentrations of 18.5 [12.8–20.5] nmol/L to 820 [730–1251.3] nmol/L and the 2-hour group increasing from baseline concentrations of 22 [15.5–22] nmol/L to 635 [401–892.5] nmol/L. Following the discontinuation of UVB exposure, 25-OHD gradually declined and was not significantly different from baseline concentrations at 7 and 4 months for the 12-hour and 2-hour groups, respectively. Dietary vitamin D3 (2.5 IU/g as dry matter basis), provided through wet cat food alone, appeared insufficient to support sustained plasma 25-OHD concentrations. These findings strongly suggest that blue-tongued skinks rely on UVB exposure to increase their 25-OHD concentrations. Moreover, the shorter 2-hour exposure provided a significant rise in 25-OHD concentrations and remained above baseline for 4 months, suggesting the shorter exposure can benefit these animals, while potentially reducing secondary risks associated with UVB exposure.