Undergraduate Research
Pathogen prevalence and health state of birds of prey in rehabilitation
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I examined the prevalence and impact of Avipoxvirus and Mycoplasma gallisepticum on host physiology in involved birds of prey admitted to the Illinois Raptor Center.
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I used ELISAs for avian IgY antibodies against each pathogen to determine infection history of the birds.
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SKILLS: Handling of birds of prey, blood sampling, pathogen swab sampling, blood smear counting, enzyme immunoassays, antioxidant capacity assay, polymerase chain reaction, ELISAs, data analysis
Disease ecology and ecoimmunology in songbirds
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I studied the prevalence of and among songbirds at sites with feeders and sites with no bird feeding activity, including a survey of prevalence after feeders had been removed.
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I assessed immune function, antioxidant capacity, and general body condition of birds with and without symptoms of the pathogens.
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I used PCR techniques to determine differences in prevalence estimates between visual identification of pathology and molecular identification.
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SKILLS: Assembly of mist nets, bird identification, extraction of songbirds from mist nets, blood sampling, pathogen swab sampling, blood smear counting, ELISAs, antioxidant capacity assay, polymerase chain reaction, data analysis
Master's Research
University of Georgia, Poultry Science Department
Undergraduate Research
Millikin University, Biology Department
An examination of current practices of testosterone administration: comparing the effects of testosterone versus testosterone propionate implants in laying hens
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Physiologists often use testosterone propionate to generate long-term elevations of testosterone because testosterone propionate may exert stronger, more long-lasting effects.
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We implanted laying hens with silastic implants (1/4 inch, ½ inch, and 1 inch long) containing either testosterone propionate or testosterone.
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The testosterone propionate implants caused a pause in laying, leading to complete ovarian regression within days of implantation. The testosterone implants had no effect on egg-laying patterns.
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SKILLS: creation of silastic implants, insertion of subcutaneous implants, blood sampling, hormone extractions, testosterone ELISAs
Quantification of androgen receptors and androgen receptor expression in the germinal disc region of the hen
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In multiple avian species, testosterone treatment results in male-biased sex ratios, with previous work suggesting that testosterone may be acting on the germinal disk (GD) to determine which sex chromosome is retained in the oocyte. There are androgen receptors (ARs) on the GD, offering a potential pathway for testosterone to act on.
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I examined if AR mRNA testosterone and protein levels on the GD region differed between at a time right near meiotic segregation (3-5h prior to ovulation) vs. a time well before meiotic segregation (20h prior to ovulation).
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I also compared if AR mRNA expression and protein levels differed between GD and non-GD regions.
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Future: Test mineralocorticoid receptor expression - potentially allow corticosterone to influence sex ratios.
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SKILLS: maintenance of large flock of laying hens (~400 birds), dissection of ovarian tissues, DNA/RNA extraction, quantitative real-time PCR, data analysis
Intergenerational effects of urbanization on stress responses in Eastern Bluebirds (Sialia sialis)
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I examined how urbanization influences offspring stress physiology by comparing blood CORT levels of Eastern Bluebird offspring raised across a gradient of urbanization.
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SKILLS: Nest box construction, monitoring of songbird populations, blood sampling from fledglings, creation and analysis of blood smears, corticosterone ELISAs
GD
Ovaries taken from hens that received ½-inch long testosterone propionate implants.