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Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum May 2022

Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum

Electronic Theses and Dissertations

Land use practices and physical alterations of ecosystems result in habitat loss and fragmentation, while chemical alterations, such as pollutant input, reduce habitat quality and health of exposed organisms. Here, I investigated the effects of watershed- and local-scale environmental variables on the occupancy, abundance, and mercury accumulation of a threatened aquatic species (Macrochelys temminckii, i.e., alligator snapping turtle) within the southwestern periphery of its distribution. Hierarchical modeling suggested the distribution of the species is more affected by watershed-scale land-cover than local habitat, and provided a baseline estimate of average species abundance across its range in eastern Texas. Abundance …


Effects Of Anthropogenic Light And Noise On Anuran Breeding Behavior, Ashley Kobisk May 2021

Effects Of Anthropogenic Light And Noise On Anuran Breeding Behavior, Ashley Kobisk

Electronic Theses and Dissertations

The natural environment can be negatively impacted by a variety of human activities, including the production of artificial light at night and anthropogenic noise. Recent studies suggest that pollution from anthropogenic light and noise alters animal behavior. Despite being highly nocturnal and vocal animals, little attention has been given to anurans and the effects artificial light at night and anthropogenic noise have on their behavior. This study investigated the effects of artificial light at night and anthropogenic noise on anuran breeding systems in eastern Texas. Specifically, this study investigated whether (1) artificial light and anthropogenic noise altered calling behavior in …


The Effect Of Holding Time Of Whole Mare Blood On Concentration Of Progesterone, Clarissa Menefee Dec 2020

The Effect Of Holding Time Of Whole Mare Blood On Concentration Of Progesterone, Clarissa Menefee

Electronic Theses and Dissertations

The objective of this study was to evaluate if holding time had an effect on mare whole blood progesterone levels. This research was completed using 12 mares, with blood being collected on multiple cycles to get a total of 28 separate blood collections. At each collection 5 vials of blood were taken for different time treatments of 0, 12, 24, and 48 hours. The 0 hour was centrifuged within 30 mins of collection and the other 4 were refrigerated at 4℃ until the specific time treatment was finished. After they were centrifuged all the samples were stored in the freezer …


Analyzing The Longevity Of Sperm Within The Female Japanese Quail By Assessing Sperm Penetration Of The Perivitelline Layer Under Optimal And Suboptimal Conditions., Garret G. Ashabranner, Joey L. Bray Aug 2020

Analyzing The Longevity Of Sperm Within The Female Japanese Quail By Assessing Sperm Penetration Of The Perivitelline Layer Under Optimal And Suboptimal Conditions., Garret G. Ashabranner, Joey L. Bray

Electronic Theses and Dissertations

After mating, birds have the ability to store semen within the female reproductive tract. The sperm storage tubules will store and subsequently release semen to travel up the oviduct. Sperm cells that make the trek up the oviduct have a chance to fertilize the ovum. These sperm cells will bind to the perivitelline layer of the ovum and hydrolyze a hole in the perivitelline layer, where it has the possibility to fertilize the female sex cell. Analyzing the number of penetration points on the perivitelline layer is an effective way to analyze reproductive efficiency. Many environmental factor has its effect …


Analyzing The Management Practices Of East Texas Beef Cattle Producers, Hiliary Cheyenne Swor Aug 2020

Analyzing The Management Practices Of East Texas Beef Cattle Producers, Hiliary Cheyenne Swor

Electronic Theses and Dissertations

A survey of East Texas beef cattle producers was designed to evaluate the management practices that were prevalent in the area. Demographic and cattle operation data from 103 respondents were analyzed using SPSS (Version 25; Chicago, IL). This electronic-based survey was distributed through Qualtrics. Respondents were located in Angelina, Nacogdoches, or Cherokee county. Most producers (38.8%) had a Bachelor’s degree. A negative correlation was established between castration method and weaning weight (p = - 0.204). Calves were weaned 50 pounds heavier when band or surgically castrated. Females were less likely to castrate their calves or utilize a mineral program. Approximately, …


Glare Reduction By Dark Facial Markings And Bills In Birds, Clara Lebow May 2020

Glare Reduction By Dark Facial Markings And Bills In Birds, Clara Lebow

Electronic Theses and Dissertations

Avian facial plumage, bill coloration, and feather microstructure may serve one or more adaptive functions. Several researchers have proposed that dark eyestripes, bills, and facial masks aid in reducing glare, however, there have been relatively few tests of this hypothesis. Dark facial markings have been shown to have an adaptive glare-reduction function in recent field studies of a few species, but this hypothesis has never been tested in a broad multispecies analysis. It is likely that feather microstructure influences feather brightness and has an effect on the efficacy of glare reduction properties of feathers. I examined the link between dark …


Breeding Bird Response To Post Oak Savanna Restoration Seven Years Post Management In Eastern Texas, Courtney Mcinnerney Aug 2018

Breeding Bird Response To Post Oak Savanna Restoration Seven Years Post Management In Eastern Texas, Courtney Mcinnerney

Electronic Theses and Dissertations

Oak savannas were once an abundant vegetation type in the Midwestern United States that have now declined to <1% of their original distribution. Historically, natural disturbances such as periodic fire and grazing maintained oak savannas, but these have been reduced or eliminated, resulting in woody encroachment and subsequent habitat loss and degradation. In 2009-10, a baseline, pre-restoration study was completed to determine vegetation characteristics, breeding bird abundances, nest success, and nest site selection at the Gus Engeling Wildlife Management Area (GEWMA) in eastern Texas. The results showed a lack of savanna vegetation structure on degraded sites and few savanna or grassland obligate bird species. The goal of this study was to determine how breeding birds of oak savanna vegetation types in eastern Texas respond to restoration effects 7 years after initial management. Post-restoration surveys completed in 2016-17 showed a change in avian assemblages from a more woodland dominated community to grassland/savanna community. The presence and breeding of savanna obligate species dickcissel (Spiza americana) and lark sparrow (Chondestes grammacus) indicates that the restoration was successful. The presence of savanna species can be linked to the herbaceous vegetation that was restored to more closely resemble historic oak savanna structure and can quantify the success of restoration efforts.


Effect Of Protease Supplementation In Broiler Feed On Growth Performance, Carcass Yield And Total Nitrogen Retention In Fecal Matter And Litter, Jawad Al-Juboori Aug 2017

Effect Of Protease Supplementation In Broiler Feed On Growth Performance, Carcass Yield And Total Nitrogen Retention In Fecal Matter And Litter, Jawad Al-Juboori

Electronic Theses and Dissertations

ABSTRACT

The objectives of this study were to determine the effects of protease supplementation on commercial broiler performance, carcass yield, and nitrogen retention in fecal matter and litter. Total of 4,800 female (Ross 708) birds split into 96 floor pens, and randomly assigned to one of four treatment groups. Birds were placed within 96, 5’x10’ floor pens in a randomized-block design at the SFASU Poultry Research Center. Birds were randomly divided among the pens at a stocking density of 1.00 ft2/bird (50 birds/pen*24 pens/treatment=1200 birds/treatment), and reared for 49 days on used pine shavings. The target average weight for the …


Evaluation Of Absorbezz On Swine Reproductive Health And A Comparative Study Of Two Commercially Available Swine Show Feeds, Scott G. Sutton May 2017

Evaluation Of Absorbezz On Swine Reproductive Health And A Comparative Study Of Two Commercially Available Swine Show Feeds, Scott G. Sutton

Electronic Theses and Dissertations

The efficacy of a feed supplement fed to gilts and sows was tested in study I. The supplement was stated to improve reproductive soundness, conception rates, immune health, and overall well-being of livestock. Thirty gilts were split into a control group (Base diet) and a treatment group (Absorbezz® 0.32 mL on base diet). Upon completion of the trial results indicate the treatment group significantly underperformed (

Two commercially available show pig growing rations were tested in study II to find a high quality, cost efficient product. A total of 10 pigs (5 barrows, 5 gilts), at an average weight of …


Evaluation Of Different Probiotic Strains Supplemented In Commercial Broiler Rations And Their Influences On Performance, Yield, And Intestinal Microbiota., Justin M. Glasscock May 2017

Evaluation Of Different Probiotic Strains Supplemented In Commercial Broiler Rations And Their Influences On Performance, Yield, And Intestinal Microbiota., Justin M. Glasscock

Electronic Theses and Dissertations

The objective of this study was to evaluate Bacillus megaterium, Bacillus licheniformis, and Bacillus subtilis, as probiotic strains compared to Bacitracin Methylene Disalicylate (BMD) 50 as the antibiotic growth promotor, supplemented in commercial broiler rations and their influences on performance, yield, and intestinal microbiota. This trial was completed as a randomized-block design with 4,800 birds split into 96, 5’x10’ pens, and randomly assigned to one of eight treatment groups. The birds were placed at a stocking density of 1.00 ft2/bird, (50 birds/pen), and reared on used pine shaving for 55 days. Throughout the study, bird …


Effect Of Reproductive Efficiency In Regards To Workload On Peripheral Circulations Of Blood Cortisol And Leptin In The Open Mare, Michaelle K. Coker Dec 2016

Effect Of Reproductive Efficiency In Regards To Workload On Peripheral Circulations Of Blood Cortisol And Leptin In The Open Mare, Michaelle K. Coker

Electronic Theses and Dissertations

ABSTRACT

Effect of Reproductive Efficiency in Regards to Workload on Peripheral Circulations of Blood Cortisol and Leptin in the Open Mare

(December, 2016)

Michaelle Kathleen Coker, B.S., Texas A&M University

Thesis Director: Dr. John Michael Mehaffey

Quarter and Paint horse mares (n= 9) were randomly assigned to 1 of 3 groups after being blocked based by expected conception date. Groups consist of mares on no work (NW), light work (LW), and moderate work (MW). Blood was taken weekly via jugular venipuncture prior to first heat cycle from each mare. Additionally, blood was taken at time of ovulation and then weekly …


Breeding Season Avian Community Composition And Prey Availability In Eucalyptus And Slash Pine Plantations Of Southwestern Louisiana, Elizabeth J. Messick Aug 2016

Breeding Season Avian Community Composition And Prey Availability In Eucalyptus And Slash Pine Plantations Of Southwestern Louisiana, Elizabeth J. Messick

Electronic Theses and Dissertations

The increased demand for wood products related to industries such as bioenergy and paper has resulted in a need for a consistent supply of raw materials. Eucalyptus (Eucalyptus spp.) plantations have the potential to boost wood production for pulpwood and biomass feedstocks. Species characteristics such as rapid, indeterminate growth, coppice regrowth, resistance to disease and insects, and tolerance of a range of environmental conditions make these species successful short-rotation woody crops (SRWCs). Camden white gum (Eucalyptus benthamii), a more cold tolerant species, has made management of eucalyptus plantations viable in southern portions of the United States such …