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Full-Text Articles in Research Methods in Life Sciences

An Edna Assessment Of The Diamond Darter (Crystallaria Cincotta) In Its Current And Historic Distribution Range, Cameron Moore Layne Jan 2025

An Edna Assessment Of The Diamond Darter (Crystallaria Cincotta) In Its Current And Historic Distribution Range, Cameron Moore Layne

Graduate Theses, Dissertations, and Problem Reports (ETD)

Environmental DNA (eDNA) can serve as a useful monitoring tool for cryptic and imperiled freshwater stream fishes. eDNA can fill knowledge gaps regarding species’ distribution, site abundance, and habitat usage. The last known stronghold of the Diamond Darter (Crystallaria cincotta) in the Elk River of West Virginia provides an excellent test case to examine the utility of this non-invasive method of surveying rare species. Diamond Darters are one of the most newly recognized freshwater fishes in North America and are among the most imperiled U.S. fishes, having been federally listed as endangered in 2013. The cryptic behavior and limitations of …


Informing Management Of American Shad (Alosa Sapidissima) In The Carolinas: Evaluating Novel Fish Passage Approaches And Acoustic Tracking Methods, Margaret Gaither Dec 2024

Informing Management Of American Shad (Alosa Sapidissima) In The Carolinas: Evaluating Novel Fish Passage Approaches And Acoustic Tracking Methods, Margaret Gaither

All Theses

Acoustic telemetry is a valuable tool for fisheries scientists to study the movements and migratory behaviors of aquatic organisms. A critical assumption of this method is that tagged fish exhibit similar behaviors and survival rates as their untagged counterparts. To investigate this, we conducted a 12-week laboratory study on adult American Shad (Alosa sapidissima) using gastroesophageal insertion of acoustic transmitters. We implanted 80 fish with dummy transmitters and monitored tag retention and survival. Our analysis, employing a mixed effects Cox’s proportional hazards model, revealed no significant differences in survival between tagged and control fish, regardless of sex. Additionally, …


Dog Sniffing Biomechanic Responses In An Odor Detection Test Of Odorants With Differing Physical Properties, Lydia Burnett, Nicholas Hebdon, Pete A. Stevens, Monica Moljo, Lindsay D. Waldrop, Lauryn Degreeff Nov 2024

Dog Sniffing Biomechanic Responses In An Odor Detection Test Of Odorants With Differing Physical Properties, Lydia Burnett, Nicholas Hebdon, Pete A. Stevens, Monica Moljo, Lindsay D. Waldrop, Lauryn Degreeff

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Dogs are utilized in forensic science for their extensive scent detection capabilities. They are often considered the “gold standard” in field detection for targets such as illicit drugs and explosives. Despite their prevalence in the field, relatively little is known about how dogs interact with and transport volatile organic compounds through their olfactory system. In this study, two groups of dogs were utilized – Sport detection dogs (n=19) that participate in the National Association of Canine Scent Work and have achieved advanced standing through training and successful search competitions and law enforcement explosive detection dogs (n=8) which were included for …


Assessment Of American Tannin-Free Grain Sorghum As Feedstuff For Poultry: Nutrient Composition, Amino Acid Digestibility And Bird Performance, Santiago Sasia Aug 2024

Assessment Of American Tannin-Free Grain Sorghum As Feedstuff For Poultry: Nutrient Composition, Amino Acid Digestibility And Bird Performance, Santiago Sasia

All Dissertations

Given the rising cost of poultry diets, alternative ingredients like sorghum are crucial for maximizing returns without compromising product quality. Sorghum's drought tolerance and adaptability, along with its nutritional profile, make it a viable corn substitute. This dissertation examines the nutrient composition, amino acid digestibility, and performance of poultry fed with American tannin-free grain sorghum. Chapter II evaluates the impact of sorghum-based diets, with or without phytase superdosing, on broiler performance, including body weight, weight gain, feed intake, and feed conversion ratio. Results indicate that sorghum can replace corn without adverse effects on broiler performance. Chapter III explores the partial …


Microplastic Accumulation In The Marsh Periwinkle (Littoraria Irrorata), Sarah Keaton, Hannah Lukhard, Eli Windy, Manar Hasan Jul 2024

Microplastic Accumulation In The Marsh Periwinkle (Littoraria Irrorata), Sarah Keaton, Hannah Lukhard, Eli Windy, Manar Hasan

DePaul Discoveries

Contamination of oceans by microplastics (mm) currently poses a major threat to aquatic and terrestrial ecosystems worldwide. Recent attention towards this issue has raised questions about the extent to which microplastics have accumulated in the environment, and has led to an increase in studies on the effects of microplastics in various organisms. However, levels of contamination in protected natural areas are still largely unexplored, yet can offer an important empirical perspective on the issue. In addition, little is known about the potential effects of microplastics on behavior in the field. This research was conducted within the protected ACE Basin National …


Baseline Characterization Of Semen From Philippine Native Chickens: Banaba, Joloano And Paraoakan, Darcy Pamulaklakin, Carla Alilie Junsay, Consuelo Amor Estrella, Percival Sangel Jun 2024

Baseline Characterization Of Semen From Philippine Native Chickens: Banaba, Joloano And Paraoakan, Darcy Pamulaklakin, Carla Alilie Junsay, Consuelo Amor Estrella, Percival Sangel

The Philippine Agricultural Scientist

The study aimed to characterize and establish baseline data on the quantity and quality of fresh avian semen utilizing a sample of Philippine native roosters. Twenty-two heads each were acquired from breeds Banaba, Joloano, and Paraoakan. The baseline data analysis revealed significant variations in semen volume among different genetic groups, with Banaba displaying the highest volume, followed by Joloano and Paraoakan. Banaba also exhibited the highest semen pH value of 7.27 when compared to the other two genetic groups (P < 0.05). Across various genetic groups of native chickens, the majority of semen samples demonstrated a thick and creamy consistency and color (42.6%), followed by thin and creamy (32.9%), with a statistical significance of P < 0.05. Furthermore, variations in sperm concentration were observed among genetic groups, with Paraoakan having the highest sperm concentration, followed by Banaba and Joloano (P < 0.05). When the semen from Banaba and Joloano native roosters were extended in Ringer’s solution, it exhibited good motility, with more than 50% of spermatozoa in motion, even after six hours of extension. In contrast, the pooled extended semen from Paraoakan native roosters displayed poor motility, particularly after eight hours of extension (P < 0.05). The study also showed that storage temperatures did not significantly affect all the sperm quality parameters of Banaba and Joloano. However, for Paraoakan, samples stored at low temperatures of 5 – 10ºC had significantly higher percent motile and progressive sperm, and lower percent static sperm than those stored at room temperature (22 – 25ºC) (P < 0.05).


Phenotypic Plasticity In Pigmentation: Investigating Coloration Patterns In Anablepsoides Hartii Population Responses To Environmental Variation, Jasdeep Kaur May 2024

Phenotypic Plasticity In Pigmentation: Investigating Coloration Patterns In Anablepsoides Hartii Population Responses To Environmental Variation, Jasdeep Kaur

2024 Spring Honors Capstone Projects - Archive

In this study, we investigated the color-changing capabilities of Trinidadian killifish, Anablepsoides hartii, through exposure to varied color conditions over defined periods of time. Our experiment aims to understand adaptive responses when killifish are subjected to different color backgrounds, exploring their mechanisms to change color. By subjecting the species to different environmental color variations, we sought to discern color change patterns, which could indicate adaptive responses related to camouflage, stress, behavior clues, and physiological adjustments. Carefully controlling environmental factors, we monitored and documented the fishes’ color changes, aiming to provide insights into the interplay between fish’s developmental plasticity and its …


Thamnophis And Their Toxic Relationship: Testing For Intraspecific Venom Variation In The Common Garter Snake, Thamnophis Sirtalis, Grace E. Coppinger May 2024

Thamnophis And Their Toxic Relationship: Testing For Intraspecific Venom Variation In The Common Garter Snake, Thamnophis Sirtalis, Grace E. Coppinger

Poster Presentations

Project Objective - Estimate intraspecific venom variation between male and female garter snakes collected from the University of South Alabama of different sizes.


Effect Of Source Of Trace Minerals On Nutrient Digestibility And Rumen Fermentation Of Dairy Cows, Cesar Velasquez Rios May 2024

Effect Of Source Of Trace Minerals On Nutrient Digestibility And Rumen Fermentation Of Dairy Cows, Cesar Velasquez Rios

All Theses

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Rock Hyrax: A Study Of Hyrax Energy Budget And Behavior Near Randilen Wildlife Management Area, Tanzania, Alice Thompson Apr 2024

Rock Hyrax: A Study Of Hyrax Energy Budget And Behavior Near Randilen Wildlife Management Area, Tanzania, Alice Thompson

Independent Study Project (ISP) Collection

Conducted at the gate of Randilen Wildlife Management Area (WMA), the purpose of this study was to contribute knowledge regarding rock hyraxes (Procavia capensis) through studying their energy budget and behavior. Rock hyraxes are small mammals belonging to the order hyracoidea. Despite being abundant across most of the African continent and parts of the Middle East, these herbivorous animals remain understudied in Tanzania. During the wet season of spring 2024, a total of 70 hours was applied to this research over the course of 10 days (April 7th to April 16th) using both qualitative and quantitative methods. The …


A Deeper Dive Into Literature Published About Pinnipeds And Cetaceans Using The Five Domain Model, Aqsa Khan, Pedro Beltran Apr 2024

A Deeper Dive Into Literature Published About Pinnipeds And Cetaceans Using The Five Domain Model, Aqsa Khan, Pedro Beltran

Posters - 2024

Research was conducted on cetaceans (whales and dolphins) (Figure 1) and pinnipeds (seals and sea lions) (Figure 2), focusing on five domains: nutrition, environment, health, behavior, and mental state. The goal was to identify the most discussed domain in existing literature. Specifically examining researchers' opinions on assessing the well-being of these marine mammals. After analyzing articles, hypotheses were formed suggesting that environmental factors are prominent for cetaceans, while behavior is the prominent domain for pinnipeds. To test these hypotheses, peer-reviewed articles were coded, providing both qualitative insights and quantitative representations of each domain's prevalence. The research uncovered the focal domains …


Materials And Methods Developed For The Recording And Analysis Of Behavior In The Common Marmoset (Callithrix Jacchus)., Christian Wintle Mar 2024

Materials And Methods Developed For The Recording And Analysis Of Behavior In The Common Marmoset (Callithrix Jacchus)., Christian Wintle

UNO Student Research and Creative Activity Fair

Materials and methods developed for the recording and analysis of behavior in the common marmoset (Callithrix jacchus).

Christian J. Wintlea, Jordan B. Hernandeza,b,c, Dobromir Dotovd, and Jonathan B. Claytona,b,e,f,g

aDepartment of Biology, University of Nebraska at Omaha, Omaha, NE, USA

bNebraska Food for Health Center, University of Nebraska-Lincoln, Lincoln, NE, USA

cDepartment of Genetics, Cell Biology, and Anatomy, University of Nebraska Medical Center, NE, USA

dDepartment of Biomechanics, University of Nebraska at Omaha, Omaha, NE, USA

eDepartment of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, …


A Comparison Of Larvicide And Garlic Mineral Salts On Horn Fly Populations, Kristina N. Dees, Benjamin J. Schrag Mar 2024

A Comparison Of Larvicide And Garlic Mineral Salts On Horn Fly Populations, Kristina N. Dees, Benjamin J. Schrag

SACAD: Scholarly Activities

For this research project, we studied three separate pastures containing Fort Hays State University’s Holstein cows. One pasture was our control group, with no horn fly protection applied. Another pasture had cattle that were fed with garlic in their mineral salts, an all-natural horn fly prevention method. Our final pasture contained cows sprayed with a larvicide. This was a single-blind study, meaning I did not know which pasture had what treatment, but my professor knew. Throughout the late summer and early fall of 2023, we went out to each pasture and took pictures of ten cows per pasture. Then, using …


A Dietary Variety: Analyzing The Impacts Of Diverse Vs Worm-Exclusive Diets On The Blanding’S Turtle (Emydoidea Blandingii), Caitlin F. Copenhaver Mar 2024

A Dietary Variety: Analyzing The Impacts Of Diverse Vs Worm-Exclusive Diets On The Blanding’S Turtle (Emydoidea Blandingii), Caitlin F. Copenhaver

Honors Program: Senior Projects (Public)

The endangered Blanding’s turtle (Emydoidea blandingii) is a species with a generally diverse diet in their freshwater wetland habitats; they consume prey such as crayfish and snails. In captivity, these options often become more limited due to logistical reasons. As ex situ conservation efforts such as captive rearing and head-starting are becoming more popular for this species, it will be important to gain more insight on how these more limited diets might affect these turtles. This study describes a comparison between diets in six captive Blanding’s turtles from September to November of 2023, with three turtles receiving only …


Quantifying Wild Pig Disturbance In Pastures And Wetlands Using Unmanned Aerial Vehicle-Derived Imagery, Wesley M. Anderson, Bethany Wight, Raoul K. Boughton Jan 2024

Quantifying Wild Pig Disturbance In Pastures And Wetlands Using Unmanned Aerial Vehicle-Derived Imagery, Wesley M. Anderson, Bethany Wight, Raoul K. Boughton

Human–Wildlife Interactions

The use of unmanned aerial vehicles (UAVs) for agricultural and environmental research has increased markedly in recent years, and a key application has been to conduct damage assessments. Invasive wild pigs (Sus scrofa) cause both agricultural and environmental damage, and past studies have utilized UAVs to quantify this damage. Each methodology has advantages, but they also have drawbacks such as high rates of damage omission or reliance upon a near-infrared camera, which may be prohibitively expensive for some land managers and scientists. Our objective was to develop a methodology that could be easily implemented to conduct wild pig …


Estimation Of Probability Of Habitat Use Of Roosevelt Elk On The Olympic Peninsula, Vincent Michael Gugliotti Jan 2024

Estimation Of Probability Of Habitat Use Of Roosevelt Elk On The Olympic Peninsula, Vincent Michael Gugliotti

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Estimating the probability of habitat use for a particular species is crucial to the direct management and conservation of that species. Without knowledge of habitat preferences, managers cannot effectively focus efforts on vital resources or landscape types. However, modelling probability of habitat use can be done in several ways which leaves room for variation and uncertainty in the estimates produced by each method. This study is an examination of the variation between two estimates of probability of habitat use while focusing on a particular subspecies of elk that inhabits a unique ecosystem relative to other elk subspecies. I modeled elk …


Compliance And Roughness In Relation To Gecko Locomotion, Brooklynn Campbell Jan 2024

Compliance And Roughness In Relation To Gecko Locomotion, Brooklynn Campbell

Williams Honors College, Honors Research Projects

Geckos move efficiently through a variety of substrates, from swaying branches to wooden fences to the sides of structures. Previous studies have studied locomotion and adhesion on manmade and rough substrates; however, the work is limited when discussing locomotion and adhesion as a relationship of compliance and roughness. Ease of movement was quantified by speed, under the assumption that the faster a gecko moves, the easier it is for the gecko to cross the substrate. Gehyra oceanica geckos from Moorea, French Polynesia were tested on substrates varying in compliance and roughness with four different treatments in total. Compliance, roughness, and …


Crayfish Tube-Feeding Methodology, Phoenix Johnson Jan 2024

Crayfish Tube-Feeding Methodology, Phoenix Johnson

Williams Honors College, Honors Research Projects

The purpose of this paper was to use a tube feeding method on crayfish to expose them to substances through ingestion rather than the gill. This was done to mimic human ingestion of substance to aid in crayfish research involving substances that are normally ingestion. This was done by using a pipette to inject grains of sand into the mouth of the crayfish. To determine if the method worked and successfully went into the stomach the grains of sand were recovered and counted under a microscope after certain increments of time post injection.


Eliciting The Effect Free Roaming Cats Have On Native Hawaiian Wildlife Using Stable Isotope Analysis, Erin Salano Jan 2024

Eliciting The Effect Free Roaming Cats Have On Native Hawaiian Wildlife Using Stable Isotope Analysis, Erin Salano

Theses and Dissertations--Biology

This study measured the concentration of the stable isotopes Carbon and Nitrogen within the tissues of free-roaming and indoor cats on the Hawai’ian islands. This study aimed to determine whether cats are consuming more human provisioned or wild food sources and whether their diet is having a negative impact on endemic species; with a focus on assessing impacts on conserved bird populations. We hypothesized that human provisioned food sources have higher levels of carbon due to the amount of corn fillers within them, while wild food sources are more Nitrogen rich. We found that indoor and feral cats sampled from …


Puberty-Associated Changes In Kiss1r, Mc3r, And Mc4r In The Ewe, Ashleigh Caitlyn Thomson Jan 2024

Puberty-Associated Changes In Kiss1r, Mc3r, And Mc4r In The Ewe, Ashleigh Caitlyn Thomson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The neural mechanisms that control the onset of puberty are not completely understood. In livestock, the onset of puberty relies on an increase in gonadotropin releasing hormone (GnRH) and luteinizing hormone (LH). Kisspeptin, neurokinin B, and dynorphin neurons (KNDy) and their receptors, Kiss1r, NK3R, and KOR, respectively, are important regulators of puberty. Previous data from our laboratory has shown that KNDy neurons may be responding to other inputs, including the melanocortin system, that will affect the timing of puberty. Given this, we examined kisspeptin receptor (Kiss1r) mRNA expression in GnRH neurons as well as examining melanocortin 3 and 4 receptor …


Walleye (Sander Vitreus) Do Not Exhibit An Aggregative Predatory Response To Larval White Sturgeon (Acipenser Transmontanus) In The Upper Columbia River In Lake Roosevelt, Washington, Seth A. Barr Jan 2024

Walleye (Sander Vitreus) Do Not Exhibit An Aggregative Predatory Response To Larval White Sturgeon (Acipenser Transmontanus) In The Upper Columbia River In Lake Roosevelt, Washington, Seth A. Barr

EWU Masters Thesis Collection

Seasonal prey abundance can drive predatory fishes to aggregate in areas of high prey density. This project aimed to determine whether Walleye (Sander vitreus) exhibit an aggregative predation response to larval White Sturgeon (Acipenser transmontanus) drifts in the Lake Roosevelt system which is a reservoir of the Columbia River in Washington State. Populations of sturgeon are threatened worldwide, and are in need of conservation research. Walleye are a popular nonnative piscivorous game fish that were accidentally or illegally introduced to Lake Roosevelt in the 1950’s. Walleye in this study were obtained by gillnetting during White Sturgeon pre-spawn, peak spawn, and …


Hypothalamic Manipulation Of The Anuran Hpg Axis: Alternative Hormones And A Non-Invasive Administration Route For Amphibian Assisted Reproductive Technologies (Art), Erin Michelle Saylor Dec 2023

Hypothalamic Manipulation Of The Anuran Hpg Axis: Alternative Hormones And A Non-Invasive Administration Route For Amphibian Assisted Reproductive Technologies (Art), Erin Michelle Saylor

Theses and Dissertations

Amidst the amphibian extinction crisis, in situ and ex situ amphibian species conservation initiatives utilize assisted reproductive technologies for optimal genetic management of captive and wild populations. Development of effective, simple, low-cost methods for obtaining gametes for artificial fertilization, sperm biobanking, or natural breeding alleviates obstacles for institutions or programs to apply reproductive technologies. Objectives herein include investigating the efficacy of alternative hormones for inducing spermiation, an alternative hormone administration route for inducing ovulation, exploring the physiological effects of hormone therapy, and utilizing sperm from deceased animals for biobanking.


Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm Dec 2023

Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm

Master's Theses

This project had two primary goals: (1) to explore opportunities to further a deep-ocean vehicle’s reach using alternative pressure spheres, and (2) to implement an existing deep-ocean vehicle (lander) in active scientific research.

I gained a greater understanding of the limitations and design choices made for existing pressure spheres using Finite Element Analysis (FEA). My simplified FEA model predicted sphere failure for the existing 30% Fiber Glass 70% Nylon injection molded spheres at an external pressure of 3,954psi or 2,690m ocean-depth (only a 7.38% error compared to the tested minimum failure depth), so I determined it a valid model. I …


In Vitro And In Vivo Evaluation Of Antimicrobial Activity, Oocyst Sporulation Rate, Oocyst Integrity And Oocyst Infectivity In Eimeria Maxima M6 Oocyst Suspensions Treated With Chlorhexidine Salts In Comparison With Potassium Dichromate, Lauren Laverty Dec 2023

In Vitro And In Vivo Evaluation Of Antimicrobial Activity, Oocyst Sporulation Rate, Oocyst Integrity And Oocyst Infectivity In Eimeria Maxima M6 Oocyst Suspensions Treated With Chlorhexidine Salts In Comparison With Potassium Dichromate, Lauren Laverty

Graduate Theses and Dissertations

Eimeria species oocysts cause coccidiosis, one of the costliest diseases in the poultry industry. Coccidiosis infections cause significant economic losses due to reduced performance in chickens and turkeys. The objective of this thesis was to determine fecal bacterial recovery from chlorhexidine (CHX) salt suspensions containing Eimeria maxima M6 oocysts and evaluate the effect of CHX salts on oocysts during long-term cold storage. For bacterial recovery experiments, CHX digluconate and CHX gluconate were tested at different concentrations on poultry fecal slurries during oocyst shedding. Eimeria maxima M6 oocysts were evaluated in CHX salt suspensions to test the effect on oocyst degradation …


Impacts Of Disturbance And Nutrient Addition On Coastal Dune Arthropod Communities, Kayla Beitzel Dec 2023

Impacts Of Disturbance And Nutrient Addition On Coastal Dune Arthropod Communities, Kayla Beitzel

Honors Theses

Coastal dune ecosystems are globally distributed ecosystems that occur from the tropics to the poles and serve as the first line of defense during storms. They are critical habitats for a variety of organisms and also play a critical role in stabilizing coastal habitats. These systems face increased pressure via urban development, recreational expansion, and sea-level rise (Newman et al. 2023; Webster et al. 2005). Insects are vital consumers in coastal ecosystems and act as regulators of plant growth. Low-diversity ecosystems, like coastal dune systems, often contain a higher abundance of low-diverse insect consumers (Ripple et al. 2021), which can …


Demographics, Sexual Dimorphism, And Ecological Aspects Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Usa, Brian M. Becker Dec 2023

Demographics, Sexual Dimorphism, And Ecological Aspects Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Usa, Brian M. Becker

Graduate Theses and Dissertations

The need to study and monitor amphibian populations is increasing along with the threats to their population stability and persistence in nature. Northwest Arkansas is one of the fastest growing areas in the nation and with that growth comes rapid changes in land use, massive alterations to habitats, habitat loss, and the introduction of nonnative plants and animals. Ambystoma annulatum (Ringed Salamander) is an Ambystomatid endemic to the Ozark and Ouachita Mountains of southern Missouri, northern and western Arkansas, and eastern Oklahoma giving it a relatively small distribution compared to most Ambystoma. Therefore, Arkansas constitutes a significant portion of the …


Unlocking The Mysteries Of Opportunism: Neuroendocrine Insights From An Aseasonal Breeder (Taeniopygia Guttata), Jessica A. Moodie Dec 2023

Unlocking The Mysteries Of Opportunism: Neuroendocrine Insights From An Aseasonal Breeder (Taeniopygia Guttata), Jessica A. Moodie

Graduate Theses and Dissertations (2019 - present)

The regulation of reproductive physiology in animals is mediated by the Hypothalamus-Pituitary-Gonad (HPG) axis. In seasonal breeders, a conserved reciprocal switching of deiodinase enzymes alters thyroid hormone signaling, which controls HPG activity. This study tested the hypothesis that neural regulation of the HPG axis as described in seasonal systems is conserved and repurposed to respond to other cues in aseasonal species. Using water deprivation and nest restriction in the opportunistic Zebra Finch, we were able to create a breeding group and non-breeding group, confirmed by egg laying and changes in ovarian anatomy. Breeding females had clear follicular hierarchy, increased ovary …


Determination Of P Availability In Feedstuffs And The Effect Of Feedstuffs And Anti-Nutritional Factors On Secretory Iga Production And Host Nutrient Losses In Poultry, Benjamin Parsons Dec 2023

Determination Of P Availability In Feedstuffs And The Effect Of Feedstuffs And Anti-Nutritional Factors On Secretory Iga Production And Host Nutrient Losses In Poultry, Benjamin Parsons

Graduate Theses and Dissertations

The availability of P in feedstuffs and the effect of feedstuffs, feed additives, and anti-nutritional factors on secretory IgA (sIgA) production in chickens were evaluated. A rapid method was developed using the precision-fed rooster assay to evaluate phytic acid disappearance, P digestibility, and phytase efficacy. Further, exogenous phytase was found to be effective at degrading myo-inositol 1,2,3,4,5,6-hexakis, however, the enzyme was less efficient at P release from lower inositol phosphates. The availability of P in feedstuffs was found to be affected by dietary Ca content, where increasing Ca linearly reduced (P < 0.05) both phytic acid hydrolysis and P digestibility. For example, the standardized ileal digestibility of P was reduced from 73 to 47% in soybean meal when the dietary Ca content was increased from 0.30 to 0.75%. The digestibility of P in distillers dried grains with solubles (DDGS) and corn fermented protein (CFP), however, was high across all Ca levels (71 to 80%). Relative P bioavailability based on tibia bone ash was also found to be high for DDGS and CFP, being 81 and 78%, respectively. Upon further evaluation, it was observed that utilizing low dietary Ca levels (0.30%) when P digestibility in individual plant-based feedstuffs was determined overestimated the P digestibility in practical grower diets by up to 16 percentage units. Utilization of higher Ca levels (0.75%) when P digestibility in individual plant-based feedstuffs was determined, however, resulted in calcualted P digestibility values that were within 1 to 3 percentage units of the measured digestibility in practical grower diets. Aside from P, feedstuffs were also evaluated to determine their effect on sIgA production in the intestine. Roosters excreted approximately 6 to 30 mg of sIgA / 24 h. Further, the proportional contribution of sIgA to total endogenous amino acid (AA) losses ranged from 1 to 13%, with the greatest contribution being observed for Trp. The addition of casein to a protein-free diet increased (P < 0.05) sIgA production in both roosters and broiler chickens. There was no change (P > 0.05) in sIgA production compared with the protein-free diet …


Assessment Of Dietary Energy And Amino Acid Diet Formulation In The Modern Broilers, Matheus Freitas Costa Dec 2023

Assessment Of Dietary Energy And Amino Acid Diet Formulation In The Modern Broilers, Matheus Freitas Costa

Graduate Theses and Dissertations

As a result of the advancement of genetics, understanding broiler requirements for dietary energy and amino acids is essential for improving live performance and carcass characteristics. The energy system used to formulate diets in poultry is based on metabolizable energy (ME); this equation can be described as the total amount of energy in the feed minus gases and feces. However, the net energy (NE) system may be the best depiction of the energy utilized by birds for production and maintenance purposes once the heat increment (HI) is measured. Thus, a series of studies were conducted to establish the responsiveness of …


The Effects Of Probiotics And Environment On The Swine Gut Microbiome, Bin Zuo Dec 2023

The Effects Of Probiotics And Environment On The Swine Gut Microbiome, Bin Zuo

Graduate Theses and Dissertations

The gastrointestinal tract is crucial for nutrient absorption and immune system functionality. It employs a synergistic approach, merging physical and biochemical defenses, to counteract pathogens that enter through dietary or other external routes. This system also facilitates the breakdown of complex carbohydrates, a process beyond the host's innate capacity. In swine, gut microbiota early colonization plays a significant role in several physiological developments, shaped by a variety of determinants including maternal factors and environmental conditions. In the swine industry, the shift to indoor pig farming enhances efficiency but limits soil interaction, potentially impacting gut microbiota diversity. Additionally, the practice of …