Life Sciences Commons^™

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 …

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 …

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 …

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 …

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 …