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Occurrence Of Antibiotic Resistance In Environmental And Amphibian E. Coli Isolates Associated With Cattle And Aquatic Environments, Robin Lynn Cissell

Masters Theses

The widespread use of antibiotics in human medicine and livestock production has been linked to an increase in resistant bacteria, which may carry transferable resistance factors, including integrons. Foodborne pathogens, such as Escherichia coli and salmonella, commonly reside in livestock, including cattle, and these pathogens may acquire resistance genes as a result of routine antibiotic use. As cattle are often located in close proximity to aquatic environments, they may disperse antibiotic resistant pathogens into such environments, which may lead to contamination of aquatic wildlife. We hypothesize that class 1 integrons and/or antibiotic resistant bacteria occur more frequently in environments with …

Supplementation Of Purified Fiber To Tall Fescue Grass Hay Diets, Howard Martin Blalock

Doctoral Dissertations

Experiments were conducted to define the degradation kinetics of purified fiber products compared to conventional feedstuffs. In situ analysis was conducted on soybean hulls, dried distillers grains, dried corn gluten feed, rice mill, wheat middlings, solka floc, oat fiber (200 and 300 series), corn bran, red and white wheat bran using nylon bags. In situ results determined oat fiber (300) and solka floc were most similar to soybean hulls and secondly to corn gluten feed. An oat fiber: solka floc mixture was formulated for subsequent experiments. The in vitro experiment consisted of alfalfa hay, soybean hulls, corn gluten feed, oat …

Inhibition Of Direct Prostaglandin F2Α Effects On Pre-Attachment Embryos Improves Reproductive Efficiency In Cattle, Fernando Nestor Scenna

Doctoral Dissertations

Prostaglandin F_2α (PGF_2α) has been shown to have detrimental effects on embryonic development, quality and hatching ability of embryos and pregnancy rates in cows. However, information about PGF_2α receptor (FPr) mRNA and protein in the preattachment bovine embryo is absent in the literature. The first experiment was design to identify the period of time during in vitro embryo development that is most susceptible to PGF_2α and to determine FPr mRNA and protein in bovine embryos. Prostaglandin F_2α decreased development of embryos to compact morula, but had no effect on development to blastocyst. In addition, …

Pb1633-Improving Your Backyard Wildlife Habitat, The University Of Tennessee Agricultural Extension Service

Wildlife and Fisheries

Wildlife viewing is becoming one of the most popular forms of outdoor recreation in America. Observing wildlife in one’s own backyard is not only enjoyable, but convenient as well. In some areas (especially rural settings), excellent wildlife habitat exists and viewing opportunities can be abundant. However, in a growing number of areas (especially suburbia), wildlife habitat has deteriorated or been destroyed entirely. This is particularly true in many subdivisions where the landscape was bulldozed and leveled-off prior to home construction. In either case, there are lots of ways to improve wildlife habitat around your home.

The Effects Of A Periodic Cicada Emergence On Forest Birds And The Ecology Of Cerulean Warblers At Big Oaks National Wildlife Refuge, Indiana, Dustin W. Varble

Masters Theses

Cerulean (Dendroica cerulea) nests (n=53) were monitored on Big Oaks National Wildlife Refuge in 2004 and 2005 to assess survival rates and to provide breeding habitat data. Mayfield nest success for ceruleans on the refuge was 22.0 ± 9.6% (2 SE) overall. Fifteen of 53 nests fledged an average of 2.4 ± 0.32 (2SE) fledglings per nests. Three nests (6% of total) were found parasitized by Brown-headed Cowbirds (Molothrus ater), although this should be considered a minimum estimate of parasitism because nests were not checked during incubation. One nest was destroyed during incubation by a Sharp-shinned …

Development Of Cmeabc Efflux Pump- Based Intervention Strategies Against Campylobacter, Ad'lynn Leigh Ensminger

Masters Theses

CmeABC, a multidrug efflux pump, contributes to Campylobacter resistance to a broad spectrum of antimicrobial agents and is also essential for Campylobacter colonization by mediation of bile resistance. We hypothesize that inhibition of CmeABC will not only control antibiotic resistance but also increase the susceptibility of Campylobacter to in vivo bile salts, consequently decreasing the colonization level of Campylobacter. Using both in vitro and in vivo systems, we examined the effect of an efflux pump inhibitor (EPI) MC-207,110 on the susceptibility of Campylobacter to various antimicrobials. Presence of the EPI resulted in 2- to 2048-fold reduction in the MICs …

Differential Neutrophil Function And Intracellular Signaling In Dairy Cows With Specific Cxcr1 Genotypes, Magdalena Rambeaud

Doctoral Dissertations

Mastitis continues to be the most economically devastating disease affecting dairy cows worldwide. Neutrophil recruitment to the mammary gland and neutrophil functional ability once there often determine whether a bacterial infection is eliminated or becomes chronic. A slow or ineffective neutrophil attack allows bacteria to continue their assault and generate a longer lasting and potentially more damaging infection. Since neutrophils are key players in the resolution of mastitis, and a polymorphism in CXCR1 +777 (G→C) has been associated with susceptibility to mastitis, the hypothesis of this research was that different CXCR1 +777 genotypes were associated with efficiency of in vitro …

Physiological & Behavioral Indicators Of Shad Susceptibility To Impingement At Water Intakes, Brooks Ashley Fost

Masters Theses

To address Clean Water Act regulations concerning reduction of fish impingement at water intakes (316b) I investigated approaches for identifying moribund or impaired shad under stressors of cold shock and reduced ration. In preliminary experiments, we determined the initial point of loss of equilibrium (LOE) for threadfin shad to be 7.2°C and for gizzard shad to be less than 3.5°C. I exposed shad to increasing levels of cold shock and reduced ration and then measured physiological and behavioral responses. Gizzard and threadfin shad exhibited reduced swimming performance at temperatures slightly above LOE. Cortisol and chloride showed a linear correlation with …

Dispersal, Persistence, And Areas Of Core Use Of Re-Introduced Juvenile Lake Sturgeon In The Upper Tennessee River System, Misty Dawn Huddleston

Masters Theses

The lake sturgeon (Acipenser fulvescens) historically occurred throughout the Tennessee River system but was extirpated by the 1960’s due to over-consumption, and habitat destruction and alteration from pollution, and dam construction. In response to improvements in water quality and other improvements made by the Tennessee Valley Authority (TVA), a multi-agency partnership was formed to reintroduce lake sturgeon in the Upper Tennessee River system. The initial re-introduction occurred in 2000, and to date over 45,000 fish from multiple age classes have been released.

Little is known about the behavior of the hatchery-reared juvenile lake sturgeon in this system. A biotelemetry study …

Volume 4, Number 1 (2006), Ut Institute Of Agriculture

Tennessee Land, Life and Science Magazine

Issue Highlights:

• A focus on agriculture and natural resources programs at the University of Tennessee Institute of Agriculture

Volume 4, Number 2 (2006), Ut Institute Of Agriculture

Tennessee Land, Life and Science Magazine

Issue Highlights:

• From Grow to Go for a New Bioeconomy