Open Access. Powered by Scholars. Published by Universities.®

Animal Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 325

Full-Text Articles in Animal Sciences

Assessing The Potential Of Taming Chicken Gut Commensal Bacteria Using Random Transposon Mutagenesis, Arjun Chapagain May 2026

Assessing The Potential Of Taming Chicken Gut Commensal Bacteria Using Random Transposon Mutagenesis, Arjun Chapagain

Graduate Theses and Dissertations

The chicken gut microbiome comprises hundreds of bacterial species whose functional roles remain largely unknown, in part because the tools needed to experimentally manipulate these organisms in their native community context have not been systematically developed or validated. This dissertation addresses the gap through three connected research chapters that progressively build a framework for transposon-based genetic delivery in the chicken cecal microbiome, moving from community-wide accessibility mapping to vector optimization to library preparation refinement. In Chapter 2, we established the community-level insertion landscape in chicken cecal metagenome using Himar transposon delivery via RP4 conjugation and aligned Tn-seq reads to a …


Creatures Of Habit? Impact Of Chick Feeder Tray Location On Feed Consumption At 0-7 Days Of Age, Emily Kate Green May 2026

Creatures Of Habit? Impact Of Chick Feeder Tray Location On Feed Consumption At 0-7 Days Of Age, Emily Kate Green

Graduate Theses and Dissertations

Early chick nutrition is critical for establishing target growth performance characteristics in broiler chickens. This study evaluated factors within commercial broiler houses that potentially influence feed consumption during the first 7 days. Three trials were conducted in a 12.2 x 122 m commercial broiler house to assess the effects of house sectioning, spatial barriers, and feedline location. In Trial 1, a one-way experimental design was used in which the house was divided into four equal sections using migration fencing every 30.5 m. House sections served as a fixed factor. Feed was provided using chick trays placed beneath the feed line …


Conservation Wins And Woes: A Meta-Synthesis Of Ecotourism Impacts On Primates And Local Communities, Madison Lanie Mckinniss May 2026

Conservation Wins And Woes: A Meta-Synthesis Of Ecotourism Impacts On Primates And Local Communities, Madison Lanie Mckinniss

Graduate Theses and Dissertations

Biodiversity assessments identify 612 extant species of primate, but ~50% of these species are at risk of extinction. Threats include agricultural and industrial production, urban development, and poaching. As concerns have grown regarding impacts on the environment, researchers have proposed ecotourism as a tool for conserving ecosystems while improving human welfare. Although conservation initiatives are pursued at these ecotourist sites, the presence of humans can cause additional influences on non-human primates (NHP). Primatologists have posed questions regarding implications of ecotourism on NHP, but research remains scarce. This study will investigate the practices executed at ecotourist sites where endemic NHPs reside. …


Broiler Responsiveness To Dietary Amino Acid Density In A Commercial Setting, Virginia Slick Dec 2025

Broiler Responsiveness To Dietary Amino Acid Density In A Commercial Setting, Virginia Slick

Graduate Theses and Dissertations

The majority of research assessing the amino acid responsiveness in broilers has been conducted in experimental designs utilizing pens that contain 12 to 25 birds with high replication. While this trial design is beneficial as a way to perform high replications with multiple treatments in a way that is both economically and spatially feasible, it may not accurately translate to a rearing environment more similar to that of commercial open floor housing. This research was conducted to determine if the effects of lysine driven amino acid density diets that have been found in the traditional floor pen setting correlate to …


Establishment Of Native Warm-Season Forages Using Organic Practices, Kolten Ray Wright Dec 2025

Establishment Of Native Warm-Season Forages Using Organic Practices, Kolten Ray Wright

Graduate Theses and Dissertations

Abstract Grassland agriculture is seen as a particularly sustainable form of agriculture. Many opportunities are known to use organic production methods or incorporate native warm-season grasses (NWSG) to accomplish both production goals and environmental or social outcomes. Environmental concerns have led some practitioners to question the use of organic methods to establish NWSG. As limited work has been accomplished in the northern bermudagrass belt, this project sought to compare organic establishment strategies for common NWSG species. A field trial conducted at the USDA ARS Dale Bumpers Small Farms Research Center in Booneville, AR found that NWSG establishment success in the …


Effects Of Injectable Trace Mineral Timing On Calf Performance And Health Indicators, Marie E. Goulais Dec 2025

Effects Of Injectable Trace Mineral Timing On Calf Performance And Health Indicators, Marie E. Goulais

Graduate Theses and Dissertations

One hundred and fourteen calves (average BW= 224kg ± 89kg) were utilized to evaluate the effects of injectable trace mineral (ITM) administration on calf performance and health when administered pre-weaning and at weaning. Calves were blocked by sex, stratified by age, and randomly assigned to one of the following treatment groups: 1) no ITM injection (CON), 2) ITM administered 28 d before weaning (PW), or 3) ITM administration at weaning (WEAN). Calves were vaccinated against respiratory pathogens on D-28 and D0. At weaning, cattle were transported to a local auction market, held overnight and returned the following morning. Body weight …


Impact Of Retail Display Case On Shelf-Life, Palatability, And Color-Stability Of Fresh Beef Steaks, Stephanie Elizabeth Shimer Sep 2025

Impact Of Retail Display Case On Shelf-Life, Palatability, And Color-Stability Of Fresh Beef Steaks, Stephanie Elizabeth Shimer

Graduate Theses and Dissertations

The objective of the study was to determine: the impact of two retail display cases, three beef muscles, and three packaging schemes on palatability traits, flavor development, lipid oxidation, objective and subjective evaluation of color stability, and microbial shelf-life. No muscle × package × case × day interactions were observed for any instrumental or panelist color evaluation (P > 0.851). No retail case effect was observed for TBARS, consumer sensory evaluation, or cook loss (P >0.05). A muscle × case × package interaction was observed for L* and b* (P< 0.05). No muscle × case × package observations were observed for shelf-life or palatability analyses (P > 0.05). No significant two-way or three-way interactions were observed for evaluation …


A Multicomponent Microneedle Patch For The Delivery Of Meloxicam For Veterinary Applications, Katherine Alejandra Miranda Munoz Aug 2025

A Multicomponent Microneedle Patch For The Delivery Of Meloxicam For Veterinary Applications, Katherine Alejandra Miranda Munoz

Graduate Theses and Dissertations

Veterinary medicine requires innovative drug delivery strategies to enhance therapeutic efficacy while minimizing stress and handling. This dissertation explores the development and application of biodegradable microneedle patches for the transdermal delivery of meloxicam in livestock, offering a minimally invasive alternative to traditional administration methods. The research investigates the fabrication and characterization of microneedles using polyvinyl alcohol, collagen, and chitosan blends, demonstrating their mechanical strength, biocompatibility, and ability to facilitate sustained drug release. In vitro and in vivo evaluations confirm effective skin penetration, dissolution, and localized drug delivery. Pharmacokinetic studies highlight anatomical site-dependent variations in drug absorption, emphasizing the need for …


Effect Of Marination And Storage Time On The Properties And Meat Quality Of Broiler Breast, Mayra Mabel Herrera Rivera Aug 2025

Effect Of Marination And Storage Time On The Properties And Meat Quality Of Broiler Breast, Mayra Mabel Herrera Rivera

Graduate Theses and Dissertations

Abstract The poultry industry has implemented numerous methods, as marination and aging, to improve meat quality and satisfy consumer demands. Three experiments were developed to assess the effects of vacuum tumble marination and aging on the proteins of chicken breast. These experiments utilized 0.75 % sodium chloride, 0.45 % phosphate, and water in a marinade. In experiment one, 270 fillets were allocated into six treatment groups, each comprising 45 fillets. Six days of storage time were used, marinating and storing the fillets in each group at a temperature of 4°C. Following each day of storage period, the fillets underwent a …


Analysis Of The Scleroderma / Systemic Sclerosis Etiopathology Using The University Of California At Davis (Ucd)-Ssc Chicken Line, Angeline E. Rodriguez Aug 2025

Analysis Of The Scleroderma / Systemic Sclerosis Etiopathology Using The University Of California At Davis (Ucd)-Ssc Chicken Line, Angeline E. Rodriguez

Graduate Theses and Dissertations

Scleroderma/Systemic Sclerosis (SSc) is a multifaceted autoimmune disorder affecting approximately 300,000 people in the United States. Main features include vasculitis, immune dysfunction (innate and adaptive), autoantibody production, perivascular leukocyte infiltration, and extensive tissue fibrosis. The University of California, Davis (UCD) SSc chicken line was shown to exhibit all clinical and biological manifestations of human SSc. One early and distinctive clinical sign in both humans and UCD-SSc chickens is Raynaud’s phenomenon (RP), characterized by decreased blood flow in extremities and skin lesions. RP-like lesions develop in combs of UCD-SSc chickens within one- to two-weeks post-hatch, progressing from erythema and edema to …


The Influence Of Retail Display Conditions On Ground Beef Quality And Palatability, Sarah Lynn Shoup Aug 2025

The Influence Of Retail Display Conditions On Ground Beef Quality And Palatability, Sarah Lynn Shoup

Graduate Theses and Dissertations

The objectives of these studies were to evaluate the impact of retail display case type and muscle type on meat quality attributes, including color, lipid oxidation, texture, and volatile compound profiles, as well as to assess economic implications based on retail color degradation. Case type effects were further evaluated by considering environmental factors such as temperature, air velocity, and relative humidity and their influence on the shelf life of beef patties. An economic analysis was also conducted to estimate the value of patties based on a* (redness) scores at different points during retail display. In Study 1, differences in L* …


Freezing And Shipping Optimization To Increase Quality And Profitability Of Meat E-Commerce, Paul Olaoluwaniyi Dahunsi Aug 2025

Freezing And Shipping Optimization To Increase Quality And Profitability Of Meat E-Commerce, Paul Olaoluwaniyi Dahunsi

Graduate Theses and Dissertations

Freezing remains one of the most reliable methods for preserving meat quality and extending shelf life. However, quality deterioration can still occur due to structural and biochemical changes activated during freezing, thawing, and distribution. Since the COVID-19 pandemic, consumers’ preference for bulk purchasing and online meat shopping has increased, raising questions about the best strategies to balance both quality maintenance and profitability. This thesis aimed to evaluate two key stages where frozen beef is most vulnerable to quality degradation: consumer-level freezing and post-purchase shipping. The objectives were (1) to determine the effects of product size and subsequent consumer freezing practices …


Impact Of Lighting Wavelength On Broiler Behavior, Health, And Performance, Angela Perretti Aug 2025

Impact Of Lighting Wavelength On Broiler Behavior, Health, And Performance, Angela Perretti

Graduate Theses and Dissertations

Lighting influences broiler production, health, and behavior. Due to their advanced visual system, avian species perceive a wide spectrum of light. The objective of this study was to investigate the effects of white (W, 350 to 780 nm) blue (B, 450 nm), and green (G, 560 nm) light on broiler production, processing performance, activity, fear, stress, blood cell profiles, tibiotarsi (tibia) morphology, and depth perception. Day-of-hatch by-product chicks from a Cobb 500 female line (N=600) were randomly assigned to 12 pens (N=4 treatment replicates). Body weight and feed consumption were recorded on day (D) 0, 14, 28, and 41, and …


Hepatic Lipid Metabolism Of High And Low Water-Efficient Broiler Lines Under Heat Stress, Maria Fernandez Cuadrado Aug 2025

Hepatic Lipid Metabolism Of High And Low Water-Efficient Broiler Lines Under Heat Stress, Maria Fernandez Cuadrado

Graduate Theses and Dissertations

Heat stress (HS) is one of the most critical environmental challenges negatively impacting global poultry production, significantly compromising broiler performance, welfare, and economic viability. Specifically, heat stress profoundly disrupts physiological and metabolic processes, including hepatic lipid metabolism. Two broiler lines were divergently selected for high (HWE) or low (LWE) water efficiency. Heat-stressed HWE birds showed reduced fat content compared to their LWE counterparts, and HS reduced abdominal fat content in both lines. The purpose of this study was to determine the difference in underlying molecular mechanisms involved in this divergent fat content between the lines. Day-old chicks were placed in …


Effect Of Dietary Tryptophan Supplementation And Heat Stress On Pasture Broiler Welfare And Performance, Jaelen Matthew Cherry Aug 2025

Effect Of Dietary Tryptophan Supplementation And Heat Stress On Pasture Broiler Welfare And Performance, Jaelen Matthew Cherry

Graduate Theses and Dissertations

Pasture-raised broiler chickens face temperature extremes that can threaten welfare. In the study, we evaluated whether a 0.26 % tryptophan-supplemented diet (T) improved heat stress (HS) resilience in Ross-708 broilers raised on pasture. At D14, birds began the T or remained on the control diet (C) and were moved outdoors. On D20 and 41, half of each group underwent six-hour HS; the remainder stayed under thermoneutral (TN) conditions. Weekly body weight, feed intake on D20 and D41 were recorded, and fear was measured using the Tonic Immobility (TI) test. Neither diet nor HS affected body weight. However, tryptophan supplementation resulted …


Impacts Of Toxic Fescue Seed Consumed By Pregnant Heifers On Maternal Blood Flow And Offspring Growth Parameters: Potential For Melatonin As A Therapeutic To Improve Offspring Growth, Rachel Scott May 2025

Impacts Of Toxic Fescue Seed Consumed By Pregnant Heifers On Maternal Blood Flow And Offspring Growth Parameters: Potential For Melatonin As A Therapeutic To Improve Offspring Growth, Rachel Scott

Graduate Theses and Dissertations

The southeastern United States is home to endophyte-infected (E+), toxic, tall fescue grass. Consumption of E+ fescue by livestock has been linked to fescue toxicosis, a disease reported to cost the United States beef industry around $1 billion in annual losses. The primary objective of this dissertation was to evaluate the influence of pregnant cattle consuming E+ seed during gestation on uterine artery blood flow and growth performance of female offspring. The secondary objective was to investigate melatonin supplementation as a mitigation strategy for expected fescue-associated decreases in uterine artery blood flow and offspring growth performance. The study reported in …


The Impact Of Wild Pigs (Sus Scrofa) On Avian Occupancy And Vegetation Structure, Kenneth Wilson Dec 2024

The Impact Of Wild Pigs (Sus Scrofa) On Avian Occupancy And Vegetation Structure, Kenneth Wilson

Graduate Theses and Dissertations

Invasive species, particularly wild pigs (Sus scrofa), pose a significant threat to native ecosystems through both direct and indirect impacts. Wild pigs are large-bodied omnivorous species that can consume a wide variety of plants and animals and are known for destructive foraging behaviors, which likely threatens avian communities through habitat alteration and can impact the long term structure of ecosystems where they are present.

In chapter 1, we used a combination of avian point count surveys, vegetation assessments, and camera trap surveillance to quantify how the occupancy of breeding birds in bottomland hardwood forests changed in relation to …


Neural Network Architecture Search Enabled Wide-Deep Learning (Nas-Wd) Integrated Hyperspectral Imaging Understanding For Woody Breast In Poultry Processing, Chaitanya Kumar Reddy Pallerla Dec 2024

Neural Network Architecture Search Enabled Wide-Deep Learning (Nas-Wd) Integrated Hyperspectral Imaging Understanding For Woody Breast In Poultry Processing, Chaitanya Kumar Reddy Pallerla

Graduate Theses and Dissertations

The development and implementation of a Wide & Deep (WD) learning model tailored for classification and regression tasks utilizing spectral data provides a robust solution to evaluate woody breast (WB) conditions in poultry fillets. This process begins with thorough data preprocessing, which includes loading spectral and classification datasets, imputing missing values with medians, and splitting the data into training and testing sets to ensure rigorous model evaluation. The WD model architecture integrates wide linear models and deep neural networks to harness the strengths of both approaches. The wide component excels at memorizing sparse feature interactions, while the deep component captures …


The Influence Of Commercial Salmonella Vaccination Programs On Local- And Systemic-Immune Responses And Ceca Microbiome In Egg-Type Chickens, Chrysta Noelle Beck Aug 2024

The Influence Of Commercial Salmonella Vaccination Programs On Local- And Systemic-Immune Responses And Ceca Microbiome In Egg-Type Chickens, Chrysta Noelle Beck

Graduate Theses and Dissertations

Salmonella vaccination is a widely accepted practice in the United States poultry industry. These vaccines stimulate a strong humoral response to Salmonella serovars and significantly reduce Salmonella load in the bird. In general, a Salmonella vaccination program for an egg-type pullet flock consists of two administrations of a live attenuated Salmonella vaccine at 1- and 6-wk-of-age followed by one administration of a Salmonella bacterin at 12-wk-of-age. Although these vaccines are regarded as effective against paratyphoid Salmonella infections, there are incidences of breakthrough Salmonella infections and severe injection site reactions after bacterin administration. Therefore, the main objective of this dissertation was …


Modeling Enterococcus Cecorum Horizontal Transmission To Investigate The Impact Of Perinatal Exposure On Extraintestinal Colonization, Disease Presentation, And Performance In Young Broiler Chickens, James Y. Higuita Valle Aug 2024

Modeling Enterococcus Cecorum Horizontal Transmission To Investigate The Impact Of Perinatal Exposure On Extraintestinal Colonization, Disease Presentation, And Performance In Young Broiler Chickens, James Y. Higuita Valle

Graduate Theses and Dissertations

Enterococcus cecorum (EC) has primarily been associated with osteomyelitis and lameness in older chickens. The recent emergence of pathogenic EC causing morbidity and mortality in young broiler chicken flocks requires further investigation. The purpose of this thesis was to develop a model to simulate horizontal transmission of virulent EC during the hatching phase in small scale hatchet cabinets. The model will be used to investigate novel pre- and post-hatch strategies to mitigate EC infections in young broiler chickens. The current thesis contains four chapters. Chapter I includes the thesis introduction. A literature review focusing on EC-associated disease in chickens, with …


Consumer Perceptions Of Hemp-Fed Aquaculture, Jillian Hyink Aug 2024

Consumer Perceptions Of Hemp-Fed Aquaculture, Jillian Hyink

Graduate Theses and Dissertations

Global demand for seafood has increased significantly over the past several decades and is projected to continue rising in the future. The volume of aquaculture production has also particularly increased to meet this demand in the United States and globally, offering a relatively sustainable supplement to wild fish supplies. However, conventional fish farming uses unsustainable quantities of fishmeal and fish oil as feed inputs, which raises the cost of production and introduces safety concerns associated with fish consumption. One currently underexplored potential alternative to fishmeal is hemp grain, which can provide an affordable and nutritious feed for carnivorous fish and …


Local And Systemic Inflammatory And Antibody Responses To Salmonella-Killed Vaccines In Egg-Type Pullets, Jossie Mair Santamaria Archbold Aug 2024

Local And Systemic Inflammatory And Antibody Responses To Salmonella-Killed Vaccines In Egg-Type Pullets, Jossie Mair Santamaria Archbold

Graduate Theses and Dissertations

Salmonella infection in chickens is a significant and complex challenge to manage, affecting poultry health and food safety. Vaccination against Salmonella is a promising preventative approach to control flock infection and decrease the loads of this pathogen. Vaccination strategies against Salmonella often comprise the application of live attenuated and killed (inactivated) vaccines, including inactivated autogenous vaccines. Live attenuated Salmonella vaccines stimulate both cellular and humoral immunity but can potentially return to a virulent state; meanwhile, inactivated Salmonella vaccines trigger more of a humoral response and are safer since they are entirely rendered inactive. However, there is a lack of information …


Alternative Methods For Finishing Beef Cattle: Effects On Performance, Carcass Quality, And Meat Characteristics, Michelle Johnson Aug 2024

Alternative Methods For Finishing Beef Cattle: Effects On Performance, Carcass Quality, And Meat Characteristics, Michelle Johnson

Graduate Theses and Dissertations

The objective of these studies was to evaluate the effects of alternative finishing methods on the live performance, carcass quality, and meat characteristics of beef steers. In study 1, treatments consisted of a conventional feedlot finishing diet with roughage included in the ration (FDLT); a high starch diet fed at 2-2.25% of BW with ad libitum access to bermudagrass pastures (STCH); or a high by-product diet fed at 2-2.25% of BW with ad libitum access to bermudagrass pastures (BYPD). Steers were fed their respective diets once daily and weighed every 28 days until deemed finished. Cattle were then transported and …


Migration And Breeding Ecology Of King Rails (Rallus Elegans) In Southeast Arkansas, Jessica Schmit May 2024

Migration And Breeding Ecology Of King Rails (Rallus Elegans) In Southeast Arkansas, Jessica Schmit

Graduate Theses and Dissertations

King Rails (Rallus elegans) are a secretive marsh bird species of conservation concern in Arkansas. Freddie Black Choctaw West WMA in southeast Arkansas has multiple confirmed pairs of breeding King Rails and offered an opportunity to investigate King Rail migration ecology, as well as nesting ecology and nest site selection. In Chapter 1, we determined migratory status (resident vs. migratory) and described seasonal movement. To do this, we captured and outfitted 23 birds with Argos GPS tags to track migration patterns throughout the season. We found that most of the population did not make long distance migrations but instead were …


Heterogenous Impacts Of Pathogenic Avian Diseases On Global Poultry Production, Elsbeth Hamilton May 2024

Heterogenous Impacts Of Pathogenic Avian Diseases On Global Poultry Production, Elsbeth Hamilton

Graduate Theses and Dissertations

Globally, poultry is one of the most versatile and cost-effective sources of animal-based protein. Due to its wide variety of uses and variability of growing styles, poultry production is applicable in nearly every country. With the increase of scale and concentration of production, pathogenic diseases have decreased the efficiency of production through worsened feed conversion, morbidity, and mortality. In addition to physiological health, climate largely impacts the suitable conditions for growing. With more extreme climate events, locations once ideal for poultry are less efficient due to increased resource cost. This analysis seeks to determine the heterogeneity of production and the …


Dispersal Movement And Overwintering Ecology Of A Cryptic Migratory Forest Owl, Mitchell Lee Pruitt May 2024

Dispersal Movement And Overwintering Ecology Of A Cryptic Migratory Forest Owl, Mitchell Lee Pruitt

Graduate Theses and Dissertations

Understanding species’ distributions and how a species uses its environment is a vital aspect of ecology and important for the development and implementation of conservation planning. In migratory species, with distinct breeding and nonbreeding ranges, understanding distributions is a complex endeavor. Nevertheless, evaluating movement behavior by linking seasonal distributions and identifying source areas is vital for understanding a species’ full annual cycle ecology. Understanding distributions is particularly important for predators, like birds of prey, that can exert top-down effects on community structure and ecosystem function through their influence on prey populations. Among raptors, owls are severely understudied in large part …


Evaluation Of Protein Turnover, Lipid Turnover, And Calcium Utilization On Broiler Breeder Performance, Cole Umberson May 2024

Evaluation Of Protein Turnover, Lipid Turnover, And Calcium Utilization On Broiler Breeder Performance, Cole Umberson

Graduate Theses and Dissertations

Broiler breeder performance is based upon egg production. Breeders are reared from day of hatch to ovulation with the main goal of controlling body weight. Maintaining body weight in breeders is highly emphasized prior to first egg as to reach optimum peak production feeding increases dramatically to meet energy needs. Energy is supplied to the breeder in three forms carbohydrates (fast energy), protein (medium energy), and fat (slow energy). Carbohydrates are quickly used by the breeders, while protein is constantly being utilized by the breeder for growth and egg production, fat is stored and used lastly as the energy requirements …


Determination Of Ileal Digestible Phosphorous Values In Various Inorganic Sources Meat And Bone Meal Sources, Jay Hampton May 2024

Determination Of Ileal Digestible Phosphorous Values In Various Inorganic Sources Meat And Bone Meal Sources, Jay Hampton

Graduate Theses and Dissertations

Concerns around the economic and environmental consequences of suboptimal or excess dietary P levels in broiler diets has led to increased interest in determining ileal P digestibility values for feed ingredients. Therefore, two experiments (EXP) were conducted to determine the apparent (AID) and standardized ileal digestibility (SID) of P in various inorganic phosphates and meat and bone meals (MBM) using the direct method. In both EXP 1 and 2, ileal samples were collected at 22 d post-hatch from birds fed semi-purified diets based on dextrose and corn starch containing test ingredients and one N and P free (NPF) diet for …


Effects Of Varied Fertilization, Tillage, And Supplementation Strategies On Grazing Steers And Wheat Pasture Performance, Cody Everett Gruber May 2024

Effects Of Varied Fertilization, Tillage, And Supplementation Strategies On Grazing Steers And Wheat Pasture Performance, Cody Everett Gruber

Graduate Theses and Dissertations

The objectives for the two experiments were to determine the impact of nitrogen (N) fertilizer rate, establishment method through no-till (NT) or clean-till (CT), and supplementation on stocker, wheat stand, and economic performance. Within study 1, 24, 1.62-ha pastures, were used over a two-year period. Pasture treatments consisted of a combination of N fertilization rate (100.88, 134.5, or 168.12 kg/ha), applied as broadcast urea and split between two equal applications of 50% at planting and the remaining 50% in the spring when daytime average temperatures trend above 10°C, and of NT establishment or CT establishment. Steers were weighed on arrival, …


Evaluation Of The Effect Of A Commercial Lippia Origanoides Essential Oil Extract On Salmonella Serovar Enteritidis As A Natural Alternative To Antibiotics In The Poultry Industry, Abdiel Atencio May 2024

Evaluation Of The Effect Of A Commercial Lippia Origanoides Essential Oil Extract On Salmonella Serovar Enteritidis As A Natural Alternative To Antibiotics In The Poultry Industry, Abdiel Atencio

Graduate Theses and Dissertations

The purpose of the present research was to evaluate the bactericidal activity of a microencapsulated Lippia origanoides essential oils (LOEOs) against Salmonella Enteritidis (SE) in an in vitro crop assay and in a prophylactic broiler chicken model using three low doses of the product: 75 ppm, 150 ppm and 300 ppm. Two trials of each assay were conducted. Day-of-hatch male Cobb-Vantress broiler chickens were randomly allotted to one of four groups: 1) positive control group; 2) 75 ppm LOEOs group; 3) 150 ppm LOEOs group; 4) 300 LOEOs group. Chicks were fed and watered ad libitum in heated brooder batteries …