The main goal of this thesis was to develop new methods and knowledge that will explain and predict species differences in sensitivity to dioxin-like compounds (DLCs) in birds. The important achievements and results obtained from the four experimental chapters of this thesis are summarized as follow: (1) an efficient luciferase reporter gene (LRG) assay was developed for use with 96-well cell culture plates; (2) the results obtained from LRG assay were shown to be highly correlated to available in ovo toxicity data; (3) amino acids at positions 324 and 380 within the aryl hydrocarbon receptor 1 ligand binding domain (AHR1 LBD) were shown to be responsible for reduced Japanese quail (Coturnix japonica) AHR1 activity to induce a dioxin-responsive reporter gene in comparison to chicken (Gallus gallus domesticus), and ring-necked pheasant (Phasianus colchicus) AHR1 in response to different DLCs; (4) AHR1 LBD sequences of 86 avian species were studied and differences at amino acid sites 256, 257, 297, 324, 337 and 380 were identified. It was discovered that only positions 324 and 380 play a role in AHR1 activity to induce a dioxin-responsive gene; (5) in COS-7 cells expressing chicken AHR1, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 2,3,4,7,8-pentachlorodibenzofuran (PeCDF) are equipotent inducers of the reporter gene and bind with similar affinity to chicken AHR1, however, in the cells expressing pheasant, Japanese quail and common tern (Sterna hirundo) AHR1, PeCDF is a stronger inducer than TCDD. PeCDF also binds with higher affinity to pheasant and quail AHR1 than TCDD. The results of this thesis show that embryo lethal effect of DLCs in avian species can be predicted by use of two new non-lethal methods: (1) the LRG assay and (2) determination of the identity of the amino acids at positions 324 and 380. The findings and methods described in this thesis will be of use for environmental risk assessments of DLCs.

No description available.

Die Studie untersucht im Lehr- und Versuchsgut in Köllitsch bei Torgau (Sachsen) die Wirkung von landwirtschaftlichen Vogelschutzmaßnahmen auf den Agrarflächen im Hinblick auf den Bestand an Brutvögeln und deren Nahrungsangebot. Die Ergebnisse zeigen, dass u. a. Feldlerchenfenster, neu angelegte Brachen und Ackerraine, reduzierter Einsatz von Pflanzenschutz und Düngung am Ackerrand sowie der Zwischenfruchtanbau deutlich positive Effekte auf den Brutvogelbestand und dessen Nahrungsangebot an Insekten, Spinnen und Samen haben. Auf den Untersuchungsflächen, insbesondere auf den Brachen und Ackerrainen, wurden bei Insekten 29 und bei Spinnen 19 Rote Liste-Arten festgestellt.

Thesis (M.S.)--Texas State University-San Marcos, 2008. / Vita. Appendix: leaves 23-31. Includes bibliographical references (leaves 32-33). Also available on microfilm.

Thesis (Ph. D.)--University of Washington, 1995. / Vita. Includes bibliographical references (leaves [74]-80).

Thesis (M.S.)--Texas State University-San Marcos, 2008. / Vita. Includes bibliographical references (leaves 40-48). Also available on microfilm.

Thesis (M.A.)--Central Connecticut State University, 1998. / Thesis advisor: Dr. [Heather Munro] Prescott. " ... in partial fulfillment of the requirements for the degree of Master of Arts in History." Includes bibliographical references (leaves [97]-101).

Thesis (M.S.), Natural Resources, University of Wisconsin--Stevens Point, 2004. / Includes bibliographical references (leaves 47-50).

Thesis (Ph. D.)--Murdoch University, 2002. / Includes bibliographical references (p. 311-323).

Thesis (M.S.)--University of Wisconsin-Madison. / Cover title. "Perf. rpt, MN E-1-18, study 440." eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.