Beef Science Commons^™

Nitrogen-Use Efficiency Of Irrigated Rhodes Grass In Northern Wa, Carla Milazzo, Christopher Ham, Geoff Moore

Grain and other field crops research reports

Cultivation of irrigated fodder and forage crops to intensify northern beef production in the west Kimberley and Pilbara has seen significant private investment over the past decade. To support this growing investment, the Department of Primary Industries and Regional Development (DPIRD) carried out replicated, randomised trials on irrigated Rhodes grass near Broome.

High nitrogen (N) inputs are required for subtropical grasses to achieve annual growth rates of up to 40 t DM/ha and there is growing scrutiny of these systems to prevent nutrient losses to groundwater and downstream ecosystems. The research aimed to establish N (urea) response curves to five …

Assessing The Impact Of Toxic Fescue Consumption During Gestation On Muscle Growth Gene Expression And Beef Color Quality Of The Offspring, Madison Blank

Animal Science Undergraduate Honors Theses

Endophyte-infected tall, toxic fescue is the most common forage for beef cattle in the southeastern U.S. However, exposure to this forage causes detrimental effects on the health of gestating cattle. The exposure to toxic fescue during gestation has been shown to impact fetal development during pregnancy and their offspring’s subsequent growth. However, limited information is currently available on the impact of this exposure on the meat quality of the offspring. Our objective is to determine how the dam’s exposure to toxic fescue during gestation impacts the beef color and quality of the final offspring.

A total of 22 animals (11 …

Effect Of A Probiotic Microbial Gel Jointly With Two Versions Of Supplemental Direct-Fed Microbials In Receiving Cattle Diets On Growth Performance And Health, John Mitchell

Biological Sciences Undergraduate Honors Theses

The objective was to assess the effect of a probiotic microbial gel (BIOFRESH® Microbial Gel, Agrarian Solutions) administered on arrival in combination with feeding one of two different direct-fed microbials (DFM 365a or DFM 365b, Agrarian Solutions) on the health and growth performance of stocker calves at high risk for bovine respiratory disease (BRD). Beef heifer calves (n = 292, BW = 476 ± 5 lb) arriving on 3 separate receiving dates were used in the 42-day receiving study. On arrival (d -1), heifers were processed, stratified by d -1 body weight, and then assigned randomly to 9 pens (10 …

The Effect Of Including A Yeast Culture Containing Essential Oils In Receiving Cattle Diets On Growth Performance And Health, Taylor Deanna Foster

Animal Science Undergraduate Honors Theses

Due to the increased risk of bacterial populations developing resistance to current antibiotics, consumer perceptions surrounding the utilization of antibiotics use in cattle, and the endemic incidence of bovine respiratory disease (BRD) among growing and finishing cattle, alternative management strategies to improve the health of cattle must be developed. The objective of this study was to evaluate the use of a supplement containing a yeast culture and an essential oils blend (YEO) on the health and growth performance of stocker calves at high-risk for BRD. Crossbred male beef calves (n = 185) received on two separate dates were used in …

Influence Of Increased Supplementation Of Organic-Complexed Zinc To Beef Cows During Gestation: Effects On Preweaning Health Of Offspring, Naija N. Sharpley

Animal Science Undergraduate Honors Theses

The objective of this study was to determine the effect of increasing zinc supplementation from organic-complexed sources to beef cows during gestation on calf performance. In May 2025, during gestation, Angus crossbred cows were confirmed pregnant with female sexed semen (n = 83) and enrolled in the current study. Cows (4.7 ± 2 years of age and 531 ± 84.4 kg body weight, mean ± standard deviation) were allotted to 4 groups (20 to 21 cows/group) based on, sire of heifer calf, cow age, and cow body weights taken at weaning. Assigned groups received 1 of 2 treatments (2 groups/treatment): …

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 …

To Hold Or Sell Breeding Cattle In The Rangelands, Department Of Primary Industries And Regional Development, Western Australia

Animal production and livestock factsheets

In a dry season where feed, water and finances are limited, removing less productive animals as soon as possible is a good option. This will free up feed for more productive animals and help preserve ground cover.

This page provides some of the information and a process for making decisions about holding or selling breeding cattle.

Optimal Drought Management Actions For Cattle Operations On Navajo Nation, Tatiana Drugova, Kynda R. Curtis, Man-Keun Kim

All Current Publications

In this fact sheet, we examine the drought management options available to cattle operations on the Navajo Nation, the largest Native American reservation in the U.S. Specifically, we discuss the results of a study evaluating the economic outcomes of two common drought response strategies: herd reduction and supplemental hay purchases. We also provide recommendations for ranchers on optimal strategies, i.e., those that maximize profits, for two rancher types, differentiated by their willingness to accept (risk-neutral) or avoid risk (risk-averse).

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.