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Development Of A Proposed Selective Medium For The Isolation And Differentiation Of P. Sordellii, Dimyana Bottros

Honors Undergraduate Theses

Clostridium, a genus of anaerobic, spore-forming bacteria, includes clinically and ecologically significant species like Clostridium difficile and Paeniclostridium sordellii. C. difficile causes antibiotic-associated colitis, while P. sordellii is linked to fatal infections and spontaneous abortions. Recent studies found both species in marine sediments, suggesting their role in environmental and wildlife health disturbances, including the 2013 mass mortality of over 300 manatees in the Indian River Lagoon. However, isolating and differentiating P. sordellii is challenging due to the lack of selective media optimized for its growth. This thesis proposes a novel selective medium tailored to P. sordellii’s physiological …

Contents, Discovery Editors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Instructions For Authors, Discovery Editors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Effects Of Essential Oils Alone Or In Combination With Monensin In An In Vitro Model Of Ruminal Acidosis, Jorge L. Bonilla Urbina

Electronic Theses and Dissertations

The objective of this study was to evaluate the effect of essential oils and/or monensin on the concentration of volatile fatty acids (VFA), ammonia, and pH in a ruminal acidosis in vitro model. Red Angus steers (n = 4; BW = 435 ± 9 kg) with ruminal and duodenal cannulas were allocated in a 4 × 4 Latin square design. Treatments were 1) Fed no essential oils (RB) or monensin sodium (MON:CON); 2) Fed RB at a rate of 14 g daily with no Mon (RB+); 3) Fed no RB and fed Mon at 400 mg daily (MON+); 4) Fed …

Use Of Fecal Inoculum From Easy And Hard Keeper Horses To Determine In-Vitro Digestibility Of Feedstuffs Used In Equine Diets, Leah Bills

Graduate Theses/Dissertations

Digestibility studies provide vital information for formulating ideal diets based on an animal’s ability to digest and absorb the available nutrients from the feed provided. The purpose of this study was to determine if there is a difference in the nutrient digestion of horses between those that have a difficult time maintaining a healthy body weight (body condition score at or below 5, hard keeper) and those that easily maintain a healthy body weight (body condition score of >5, easy keeper). Six mature geldings averaging 534.1 ± 47.1 kg were used in this study. During the experimental period horses were …

Phytogenic Feed Additives Pre- And Post-Calving And Effects Of Substituting Ddgs With Soybean Meal On Protein Metabolism In Beef Cattle, Grace H. Jardon

Electronic Theses and Dissertations

The objective of these studies was to evaluate nutritional strategies to improve beef cattle productivity through targeted supplementation and protein source manipulation. The first study investigated the effects of a phytogenic supplement (PHYT; a blend of turmeric, capsicum, and black pepper oleoresin) on colostrum yield and composition, calf passive immunity, and cow–calf performance. Twenty-three Angus-based cows were assigned to either a control group or received 250 or 500 mg/head/day of PHYT from 30 days pre-calving to 60 days post-calving. Supplementation with PHYT linearly increased colostrum fat and calf serum IgA concentrations. Milk fat, calf serum IgG, and colostrum IgM tended …

Investigating The Ruminal Metagenome Of Grass And Forage-Fed Bison To Uncover Metabolic Activities That Impact The Efficiency Of Plant Fiber Utilization, Anlly Fresno Rueda

Electronic Theses and Dissertations

This dissertation investigates the ruminal microbiome of American plains bison (Bison bison) to uncover the metabolic activities that enable efficient utilization of plant fiber, with a particular focus on bacterial composition and functional capabilities in response to forage quality. Using both 16S rRNA gene sequencing and metagenomic approaches, this research provides a comprehensive view of microbial diversity and metabolic potential in the rumen of bison, offering insights into their ecological resilience and efficiency in nutrient extraction. Chapter 2 focuses on the metabolic potential of bacterial communities in the rumen of bison fed a grass-based diet. Using high-throughput sequencing and metagenomic …

Identification Of Gut Bacterial Symbionts From Atlantic Salmon That Are Involved In Metabolizing Feed Ingredients Derived From Soybean Meal, Emily Fowler

Electronic Theses and Dissertations

In the aquaculture industry, plant-based protein sources have emerged as an economically and environmentally sustainable replacement for traditional animal protein sources. Yet, due to reduced digestibility, the presence of anti-nutritional factors, as well as an increased risk of inflammation of the digestive system, the inclusion of plant-based protein ingredients must be limited, especially in the diets of carnivorous fishes. To gain further insight on how to adapt the fish digestive tract to more effectively utilize or tolerate plant-based protein ingredients, slurry from cultured Atlantic Salmon (Salmo salar) was used as a proxy in an in vitro model system to identify …

Synchronization Protocols Utilizing Progesterone Implants Associated With Estrus Expression, Vaginal Microbiome, And Immune Response In Beef Cattle, Riley James Puck

Electronic Theses and Dissertations

This thesis aims to provide a deep understanding of presynchronization strategies and the varying factors affecting their efficacy. Beginning with a literature review of the estrous cycle and the endocrinology driving it. Building on this foundation, the physiological basis for estrous synchronization is described, followed by the advancement of pre-synchronization protocols designed to increase estrus and conception. Further, we will focus on the influence of estrus expression on insemination time and conception rates. Finally, how the immune system interacts with the conception process. In addition, the review goes beyond exogenous endocrine manipulation and dives into the emerging role of the …

Extended Days On Feed: Influences On Growth Performance, Efficiency, And Carcass Characteristics Of Steers And Heifers Of Different Proportions Of Angus And Limousin Genetics, Grace Henley Olinger

Electronic Theses and Dissertations

Recently, cattle feeders have extended days on feed (DOF) resulting in hot carcass weights (HCW) exceeding the limits of existing serial slaughter datasets. This study's goal was to determine the impact extended DOF exerts on growth performance, feed efficiency, and carcass characteristics of steers and heifers with varying proportions of Angus (AN) and Limousin (LM) genetics. In 2022, commercial AN cows from two MT ranches were artificially inseminated to 9 sires from 3 breeds (AN, LM, and Limflex (LF)) with parentage confirmed by DNA. In 2023, 216 calves (sired by 72 AN, 73 LF, and 71 LM; 105 steers and …

Stress And Behavior In Beef Calves During Weaning, Kathleen E. Tierney

Theses and Dissertations

Animal welfare in commercial livestock operations has been an increasing topic of concern. It is well known that stress can have significant behavioral and physiological repercussions. It is especially important in commercial operations to reduce stress, as animal efficiency is the leading priority. In an effort to reduce stress on animals and improve welfare in livestock operations, several studies have evaluated common husbandry practices. One of the most widely studied practices is weaning, which encapsulates the process of removing the young from the dam. Several studies have evaluated the effects of weaning on beef cattle through a variety of behavioral …

Food Finding Ability Does Not Predict Annual Survival In Winter Resident Birds, Aidan Hand

Honors Program: Senior Projects (Public)

Small non-migratory birds in temperate locations face many challenges to survive the winter. They must be able to find enough food, which is in decreased supply, to fuel the energetic demands of staying warm. Prior work has demonstrated that birds show individual variation in their foraging behaviors that could contribute to the discovery of new foraging patches, such as novel environment exploration. A better ability to discover new food sources could increase a bird’s chance of surviving the winter by increasing its access to new food patches. To test this hypothesis, we used radio frequency identification (RFID)-enabled bird feeders to …

Group And State-Specific Estimation In Animal Movement Models Using A Bayesian Approach, Anita Bhandari Sharma

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This research study investigates statistical approaches for modeling the movement patterns of white-tailed deer in Louisiana using GPS tracking data. We start by classifying the latent behavioral states using a hidden Markov model (HMM) and then integrate those inferred states into a state-dependent step selection framework to evaluate the land cover preferences. Standard HMMs, however, assume the same movement patterns for all animals, overlooking the differences due to characteristics such as sex, age, breeding season, etc.

To address this limitation, we extend the modeling framework to incorporate the group-level structure defined by similar characteristics or conditions to assess whether such …

Knowledge And Acceptance Of Insects As Feed Source For Poultry Production In Conflict Affected Regions Of Cameroon, Chaba F. Ambele, Ngantu Harrison, Shaphan Y. Chia, Zewdu Abro, Komivi S. Akutse, Akum E. Akumeyam, Chrysantus M. Tanga

All Peer-Reviewed Publications

Globally, insects are increasingly being considered as sustainable and complementary feeds for poultry production. However, there is a lack of information on the perception of people in vulnerable and conflict-affected communities in Cameroon. This paper presents a survey on awareness and willingness to integrate insect meals in poultry feeds in the Northwest and Southwest regions of Cameroon. During this survey, purposive and snowball sampling procedures were used to collect data from 253 households. Among those interviewed, 32% were internally displaced people and 68% residents. In general, 97% of the respondents were aware that insects are a natural food source for …

Mapping Global Research On Mycotoxins In Aquafeed From Scientometric And Critical Perspectives, Menaga Meenakshisundaram, Sudarshan Shanmugam, Jimmy B. Mboya, Felix Sugantham, Kevin Obiero, Jonathan Munguti, Sunday Ekesi, Sevgan Subramanian, Shaphan Y. Chia, Dennis Beesigamukama, Rodrigue Yossa, Chrysantus M. Tanga

All Peer-Reviewed Publications

The global significance of mycotoxins in aquaculture is evident. However, regional vulnerabilities, effects, and inconsistent regulations on mycotoxin contamination remain underexplored. This study integrates a scientometric analysis of research on mycotoxins in aquafeed, published from 1992 to 2023 in Web of Science, with a conventional review of their occurrence in aquafeed and feed ingredients. Bibliometric tools, VOSviewer, and biblioshiny, were used to analyze global research trends, collaborations, and themes. We found a total of 181 publications, authored by 938 researchers from 49 countries, with Brazil leading (25 publications). The Toxins journal accounted for the most publications (23). Aflatoxins, particularly aflatoxin …

Unraveling The Potential Of Black Soldier Fly Larvae As A Sustainable Protein Source For Nile Tilapia Production In Diverse Aquaculture Systems, Jonathan Munguti, Mavindu Muthoka, Jimmy B. Mboya, Domitila Kyule, Menaga Meenakshisundaram, Chrysantus M. Tanga

All Peer-Reviewed Publications

Aquaculture plays a critical role in global food security, with Nile tilapia (Oreochromis niloticus) recognized for its adaptability and robust growth. However, traditional feeds, heavily reliant on fishmeal (FM) and soybean meal, face economic and environmental challenges. In response, black soldier fly larvae meal (BSFLM) has emerged as a promising, nutrient-dense alternative. This review synthesizes existing literature on BSFLM’s nutritional profile and its suitability for Nile tilapia diets, while acknowledging that the data come from diverse independent studies conducted under varying environmental conditions and husbandry practices. BSFLM consistently provides high-quality protein (29.9%–48.2%), aligning with tilapia’s requirements, and is rich in …

Characterization Of The Biofilm-Forming Ability And Certain Virulence Characters Ofaeromonas Spp. Isolates From Rainbow Trout, Türker Çelebi̇, Ertan Emek Onuk, Esra Demi̇rbaş, Gökçen Di̇nç

Turkish Journal of Veterinary & Animal Sciences

Aeromonas spp., commonly found in the aquatic environment, cause infections in both fish and humans. Their pathogenicitydepends on various virulence factors and ability to form biofilm. The current study aimed to determine the biofilm-forming capabilitiesand certain virulence characteristics of 25 Aeromonas spp. isolates obtained from rainbow trout in Türkiye. The biofilm-forming abilitiesof isolates were investigated comparatively using Congo red agar (CRA), the tube method (TM), and tissue culture plates (TCPs).Potential virulence factors, including hemolytic activity, gelatinase production, serine protease activity, DNase activity, and motility,were evaluated using phenotypic tests. Additionally, the distribution of four known virulence genes, namely aerA, exu, fla, …

Effects Of A Diet Supplemented With A Blend Of Protected Organic Acids And Essential Oilson Growth Performance And Cecal Microbiota Composition In Broilers, Mehmet Akan, Kadi̇r Serdar Di̇ker, Serdar Özlü, Murat Çelebi̇, Seyyi̇de Sariçam İnce, Barişhan Doğan, Okan Eli̇bol

Turkish Journal of Veterinary & Animal Sciences

Organic acids (OAs) and essential oils (EOs) have several positive effects on the gut microbiota of broilers. In this study, weaimed to determine the efficacy of a blend of protected OAs and EOs [P(OA+EO)] on the growth performance and cecal microbiota ofbroiler chickens. A total of 160 Ross 308 broiler chickens, including 80 male and 80 female birds, all 1 day old, were randomly distributedbetween the control group (basal diet) and the treatment group [basal diet + 300 g/t P(OA+EO)] according to an 8-pen arrangementwith 4 replicates of 20 birds. Body weight (BW), body weight gain (BWG), feed consumption (FC), …

Précis Of The Edge Of Sentience: Risk And Precaution In Humans, Other Animals, And Ai, Jonathan Birch

Animal Sentience

We often face grave practical decisions that seem to hinge on whether a system is sentient. This family of cases includes invertebrate animals, people who are unresponsive after brain injury, fetuses, neural organoids, and now AI technologies. We must decide what to do despite ongoing disagreement about the nature of sentience. In our state of uncertainty, we should pragmatically transform the question from “Is it sentient?” to “Is it a sentience candidate, an investigation priority, or neither?”. When a system is a sentience candidate, it is negligent to fail to consider precautions. We should instead evaluate precautions for their proportionality …

A Multifactorial Approach To Improve Piglet Health And Survival, Aryeri Stephanie Bardales Castellanos

Electronic Theses and Dissertations

Pre-weaning mortality (PWM) remains a significant challenge in modern swine production systems, particularly in the context of hyper prolific sows. Although genetic selection has successfully increased litter sizes, these advancements have also intensified physiological stress on sows and increased the vulnerability of neonatal piglets. The majority of PWM occurs within the first 72 hours postpartum, with crushing by the sow as the leading cause of death. Additionally, iron deficiency anemia remains one of the most widespread nutritional disorders in piglets, further compromising survival, immune function, and growth. This thesis adopts a multifactorial approach to evaluate two management interventions aimed at …

The Effects Of Flaxseed Oil-Based Supplementation On Feeding Behavior, Performance, Follicular Dynamics, And Embryo Production In Beef Cattle, Kendal Lynn Green

Electronic Theses and Dissertations

This review seeks to provide an overview of fatty acid supplementation in cattle, opening with their structural and functional properties. Nutritional supplementation helps to regulate the precursors and substrates crucial to reproduction. This review aims to examine nutritional supplementation strategies, the role of fatty acids on follicular dynamics, and their impact on embryo production. The base of literature regarding lipid supplementation is vast, with varying results found across studies. Comparing results from prior studies remains difficult as there is a vast range of lipid sources used in beef and dairy animals. The emphasis of this review was placed on evaluating …

Management Strategies To Improve Gastrointestinal Health And Productivity Of Native And Dairy-Derived Steers Fed In Confinement, Becca B. Grimes Francis

Electronic Theses and Dissertations

The objective of this dissertation was to evaluate strategies to mitigate metabolic disorders in confinement fed steers. The first study was conducted on yearling beef steers to investigate the effect of a rumen buffer, calcium magnesium carbonate (CMC), when fed with or without tylosin phosphate (TYL), on growth performance, rumination activity and liver abscess prevalence. Supplementation of a rumen buffer was not an effective alternative to a feed-grade antimicrobial for the control of liver abscesses in beef steers. Supplementation of CMC reduced DMI, thus negatively influencing BW and ADG. No associative effects of CMC and TYL were observed for any …

Impact Of Natural Feed Additives And Monensin Sodium On Growth Performance In Feedlot Cattle, Thiago Lauro Maia Ribeiro

Electronic Theses and Dissertations

The objective of this dissertation was to investigate how phytogenic feed additives and a pulse feeding monensin sodium strategy would affect growth performance in the receiving and finishing feedlot phases. Three randomized complete block design feedlot experiments and one pooled analysis were conducted to determine the effects of the feed additives and management strategies used in newly weaned and finishing beef cattle. The objective of these experiments were 1) determine if a blend of capsicum oleoresin, clove essential oil, and garlic essential oil (CCG) influences cattle performance, sera metabolites or health outcomes during the feedlot receiving phase; 2) determine if …

Effects Of Ionophore And Yeast Addition To The Diet On Starch Digestion And Rumen Andblood Parameters In Sheep With Subacute Rumen Acidosis, Şevket Evci̇, Mehmet Aki̇f Karsli, Mehmet Demi̇rci̇, Gökhan Şen

Turkish Journal of Veterinary & Animal Sciences

This study aimed to investigate the prevention of acidosis in ruminants, which causes yield and financial losses, and toevaluate the effects of feed additives on starch digestion. Four male Bafra yearling lambs with cannulated rumens were used in a 60-daystudy. Each lamb underwent 10 days of adaptation to a ration and 5 days of sampling for four different rations including a control ration(CR), monensin ration (MR), Saccharomyces cerevisiae ration (SR), and a ration with the combination of monensin and Saccharomycescerevisiae (MSR). The experiment followed a 4 × 4 Latin-square design. Dry matter intake and digestion rates were recorded as 2404 …

Evaluating And Mapping Habitat Suitability And Effects Of Woodland Treatment On Breeding Pinyon Jays In Colorado, Emily Diane Macklin

Electronic Theses and Dissertations

The pinyon jay (Gymnorhinus cyanocephalus) is a highly social, colonially nesting corvid endemic to the interior western United States whose populations have declined by ~72% since 1966, prompting the species’ current review for listing under the Endangered Species Act. Pinyon jays inhabit pinyon pine (Pinus subsect. Cembroides) and juniper (Juniperus spp.) woodlands and other dry conifer woodlands, portions of which are treated through tree thinning and removal for fuels reduction, ecological restoration, and habitat improvement for wildlife. As a result there is pressing need to better understand how woodland treatment and other potential drivers impact pinyon jay habitat suitability and …

Using Algal Turf Scrubber Biomass As A Feed Source For Juvenile Eastern Oysters, Taofeek Saka Jimoh

College of Graduate Studies: Theses & Dissertations

Algal turf scrubber (ATS) is an engineered system that promotes natural wastewater treatment processes and improves water quality by passing a shallow stream of nutrient rich water over the surface of a gently sloped flow-way. Algae turf scrubber biomass is a combination of micro and macroalgae, as well as micro-invertebrates, ciliates, bacteria, and more. The overall aim of the study was to reduce the feeding cost of juvenile eastern oysters by replacing the commercial microalgae diet with ATS biomass. The experiment was designed to assess the viability of replacing commercial microalgal diet with ATS biomass at different substitution levels (0, …

Longitudinal And Ensemble Modeling Of Beef Cattle Feed And Water Intakes, Nathan El Blake

Graduate Theses, Dissertations, and Problem Reports (ETD)

Beef cattle production remains a cornerstone of global food systems, providing highly bioavailable protein and essential micronutrients that are difficult to secure from plant-based foods alone. Yet this production is also resource-intensive, requiring substantial land, feed, and water inputs while contributing significantly to greenhouse gas emissions. Efficiency of dry matter intake (DMI) and water intake (WI) is central to both productivity and sustainability, but accurate measurement of these traits—particularly in grazing systems—remains a major limitation. National WI standards continue to rely on pen-level data collected in the 1950s, while most existing DMI prediction equations perform poorly when applied beyond the …

Microbial And Plant Biodiversity In Appalachian Agroecosystems And Their Implications For Soil Health, Kinsey Reed Close

Graduate Theses, Dissertations, and Problem Reports (ETD)

The sustainability of agricultural landscapes depends on understanding the complex interactions between plants, soil, and microbes. In Appalachia, a region shaped by complex terrain and long histories of human and ecological interaction, small family farms produce hay, livestock, and row crops. These agroecosystems, though often treated as “artificial” by many ecologists, have the potential to support both food production and biodiversity conservation if managed with an understanding of ecological complexity. This dissertation examines how plant and microbial diversity interact with soil and management to influence nutrient cycling, soil health, and long-term resilience in Appalachian agricultural systems. A literature review revealed …

Exploring The Ruminal Microbiome And Its Impacts On Feed Efficiency In Beef Cattle, Taylor Simone Sidney

Graduate Theses, Dissertations, and Problem Reports (ETD)

The ability for beef cattle to utilize feed efficiently is a critical determinant for both economic and environmental sustainability in livestock production. However, despite extensive research, the complex microbial ecosystem within the rumen and its relationship to feed efficiency remain incompletely understood. This dissertation explores the physiological and microbial foundations of feed efficiency by characterizing how rumen microbial communities and their functions differ among beef cattle with divergent residual feed intake (RFI) phenotypes and how the RFI status of beef cattle influenced their response to dietary interventions such as supplementation with a Bacillus-based feed additive. In the first study, …

Bioresource Management Via Least Cost Feed Formulation For Red Tilapia (Oreochromis Sp.): Application Of Linear Programming Technique, Boudjema Kamel, Redhouane Benfares, Affaf Kord, Toufik Milla, Belkacem Guenachi, Lynda Frai, Rachida Itcher, Hocine Kherzane

Journal of Bioresource Management

The method of linear programming (LP) was utilized to determine the relationship between the composition of nutrients of each ingredients, specifications for raw materials, cost and requirements for nutrients of the red tilapia (Oreochromis sp.), in order to define: (1) least cost ration formulation, (2) least cost diet, (3) minimum price of producing a particular diet after meeting a number of requirements. The resulting LP models were solved using the simplex algorithm. Therefore, our results show that, formulated feed had high protein content (31.92 %), Lipid (2.53), Moisture (9.10 %) and Ash (9.00 %). The utilization of diet …