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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Exploring Population Structure and Diversity Across Time in Population of American Flamingos (Phoenicopterus ruber)

Folsom, Jessica 01 January 2023 (has links) (PDF)
Dispersal and connectivity within a population often promotes overall diversity and adaptive potential, therefore a disruption of existing patterns of connectivity by local extinction can have significant consequences for the affected species. However, the extent of these impacts on recovery is not always known. American flamingos (Phoenicopterus ruber) present an ideal opportunity to investigate how changes in gene flow influence within population diversity and genetic structure over the span of a century for a recovering population. Flamingos were highly sought-after by hunters for their meat and feathers, and as a result, the Florida population was extirpated by the beginning of the 20th century. Despite high vagility and the presence of nearby flocks nesting in the Caribbean, the Florida population has yet to show significant recovery. In this study I used whole-genome sequencing (WGS) to assess historical samples maintained in museum collections, as well as contemporary samples of wild birds and captive flocks, to estimate genetic diversity, reconstruct gene flow, and evaluate population structure across time. Genetic diversity was found to have either increased or stayed constant over time, indicating the diversity lost through hunting may have been partially recovered in contemporary birds. However, evidence of inbreeding was found to be high in contemporary birds compared to their historical counterparts. The population structure of the species was found to be largely unaffected by the extirpation, with both contemporary and historical samples showing clear evidence of panmixia throughout populations in the northern Caribbean. The captive population had higher diversity and lower inbreeding than wild birds and were not significantly differentiated from the wild population, making these flocks possible sources for reintroduction projects. The data gathered in this study constitutes the first use of whole-genome sequencing to study the American flamingo population, aiding in both the management and recovery of flamingo populations.
162

Behavioral, Morphological and Genetic Differentiation Among Populations of Enyaliopsis

Macamo, Laura 01 January 2023 (has links) (PDF)
The study of biodiversity is a fundamental part of the study of the ecosystem's function and stability and how changes in the habitat shape the interaction between species. In recent years, the classification of species benefited from the analysis of several types of data to aid the distinction of morphologically similar species. Enyaliopsis iaculator (Naskrecki and Guta, 2019) is a species endemic to central Mozambique. Different populations of E. iaculator were reported to exhibit differences in the time of the day the mating call is displayed, but no morphological differences were reported. Since call behavior tends to be species specific and it has been used to classify calling insects, the question of whether populations of E. iaculator with differences in call behavior belong to the same species or if there are more than one species within what is now taxonomically classified as E. iaculator still stands. Here, I took a holistic taxonomic approach to investigate the relatedness within populations of E. iaculator with different call behaviors using genetic, acoustic and morphological characters. Phylogeny reconstruction based on COII indicated a divergence between populations with different call behaviors. In addition, analyses of the acoustic signal and genitalia shape supported the existence of two lineages based on calling behavior. Together, these data suggest that taxonomically identified E. iaculator is composed of two geographically distinct species that should be managed separately with regard to conservation. Additionally, this study provided some insights on the greater phylogeny of the genus Enyaliopsis and the subfamily Hetrodinae.
163

Detection of Cardiovasopathy in Dogs by Quantitative Analysis of Angiocardiograms

Boucher, John Holly January 1968 (has links)
No description available.
164

Assessment of Daily Behavioral Activity Patterns using Electronic Data Loggers as Predictor of Parturition, Dystocia and Metritis in Lactating Holstein Cows

Titler, Mallory L. 09 September 2014 (has links)
No description available.
165

Cobra

Humes, Cathryn Amanda 14 May 2014 (has links)
No description available.
166

Biochemical and Genome-Based Analysis of Polysaccharide Degradation by Ruminococcus Albus

Reveneau, Carine January 2002 (has links)
No description available.
167

Effects Of Dietary Potassium Carbonate And Fat Concentration in High Distiller Grain Diets Fed To Dairy Cows

Lamar, Kathryn C. 17 October 2013 (has links)
No description available.
168

Bat House Use in Central Florida, With Emphasis on Nycticeius humeralis and Tadarida brasiliensis cynocephala

Finn, Laura Seckbach 01 January 1997 (has links) (PDF)
Bat houses and roost sites utilized by Tadarida brasiliensis and Nycticeius humeralis were studied in four central Florida counties. Temperatures were monitored in occupied roosts and in bat houses. It was determined that the presence of bats affects roost temperature. The mean temperature in the bat house that was preferred at the Seminole Community College (SCC) site was above ambient temperature a significantly greater amount of time than mean temperature in the other style houses located at that site. A colony of bats roosting in buildings on the property of SCC was successfully relocated into bat houses located .4 kilometers from the main roost. At another Sanford site (Aikins). a bat house occupied by both species, was moved to a site located 5 miles to the north . During the bat house move, Tadarida did not relocate successfully and left prevolant pups behind. Nycticeius remained at the new site for two months. Bats appear to prefer bat houses and roosts with west or northwest orientations, but have occupied all other orientations.
169

Contingency Analysis of the Agonistic Behavioral Sequence in Sceloporus undulatus hyacinthinus

Allison, Deborah 01 February 1987 (has links)
A contingency analysis of the sequence of actions associated with agonistic behavior of resident and introduced male Sceloporus undulatus nya irthirus was carried out to determine the degree of stereotypy. During the time period April to June 1984 and 1985, caged pairs of adult male and juvenile female lizards were filmed on three occasions in order to gather data on resident males not involved in aggressive interactions. During the same threemonth time period, a different nonresident male was introduced singly into a given resident's cage on three occasions and the interactions filmed. The films were analyzed to determine which actions were agonistic, the sequence of actions and the transition frequencies from one action to another. The sequence of actions was determined to be probabilistic, that is, the occurrence of one action influenced the probability that a specific action would follow. The most probable behavioral sequence for resident males during male-male interactions was head turn-crawl-jaw snap-lateral compression-bobbing-attack. The latter three actions were unique to agonistic encounters. The introduced males expressed a similar behavioral sequence except that they very rarely attacked. The behavioral sequence of resident females during male-male interactions consisted of head turn-crawl-jaw snap-bobbing. Bobbing generally preceded jaw snapping in females when such male-male interactions were not taking place. The probabilistic nature of the display action pattern during agonistic behavior is similar to that observed in other iguanid lizards studied. Three levels of arousal were evident in resident males during aggressive interactions. These were 1) heightened awareness, 2) display and 3) attack. Again, this observation is consistent with those in studies carried out in other iguanid lizards.
170

The Relationship Between the Murine Primary Immune Response to Sheep Red Blood Cells & Heterosis

Gailor, Russell 01 December 1989 (has links)
Two inbred strains of mice, BALB/c and C57BL, were crossbred to produce Fl hybrids. This breeding scheme ensured a high degree of genetic heterozygosity as exemplified by the fact that the average weight of the Fl hybrids at 10 weeks of age was 10.1 percent greater that that of their contemporaries in the inbred parental strains. The three lines of mice were then challenged with a 0.5 ml intraperitoneal injection of two-percent sheep red blood cells (SRBC). After a 15-day period the mice were bled and their sera were microtitrated for anti-SRBC agglutinin and the titers statistically analyzed. The Fl mice were found to exhibit a highly significant (P < 0.0001) difference in serum antibody titers over both parental strains. Highly significant differences were also shown between the parental strains, the BALB/c mice being superior to the C57BL in antibody production to SRBC. The results of this work indicate a 177.1 percent degree of heterosis in the immune response of the Fl hybrid mice over that of their inbred contemporaries. These findings, coupled with general knowledge of animal genetics and performance, may indicate that the increased immunocompetence of the crossbred mice is directly related to their increased rate of growth.

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