Includes bibliographical references (leaves 226-261). / xxiii, 261 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigates nitrogen utilization in some species of rumen bacteria with the object of understanding the role of ammonia versus exogenous amino acids in relation to microbial growth. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Science, 1996?

Bibliography: leaves 151-166. / xi, 166 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis describes the development of two novel and complementary analytical approaches for assaying cyanoalanine non-protein amino acids. These assays are used to determine the distribution of these compounds both within and between plants and to identify accessions of common vetch which contain low levels of the cyanoalanine non-protein amino acids in germplasm collections. These analytical tools are used to correlate toxicity observed in animal feeding experiments with the cyanoalanine content. This thesis covers also the first report of the use of diffuse reflectance using dispersive infrared spectrometry for the "in situ" quantification of specific organic components from plant tissue as well as the first use of micellar electrokinetic chromatography for the quantitative analysis of 9-fluorenylmethyl chloroformate (FMOC) derivatised and non-derivatised components of extracts from plant material. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1997

Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on February 13, 2008) Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Wyoming, 2005. / Title from PDF title page (viewed on Nov. 2, 2007). Includes bibliographical references.

Thesis (Ph. D.)--University of Adelaide, Dept. of Plant Science, 1997. / Includes bibliographical references (leaves 151-166).

Thesis (Ph.D.) -- University of Western Sydney, 2003. / "A thesis submitted to the University of Western Sydney for the degree of Doctor of Philosophy" Bibliography : leaves 247-263.

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaf 140). Also available via the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 136-148). Also available on the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 136-148). Also available on the Internet.

Plasma and erythrocyte (RBC) free amino acids and plasma peptide and serum protein amino acid concentrations and arteriovenous (A/V) differences across the hindlimbs were determined on growing Holstein steer calves (130 kg) fed purified diets containing scy protein or urea as the sole source of dietary nitrogen. Animals were fed at hourly intervals in a constantly lighted environment in order to achieve near ‘steady-state’ metabolic conditions. Experimental trials lasted 30 days with blood samples collected on day 10 and day 30 of each trial. Plasma and Plasma and RBC free amino acids were determined from filtrates obtained by deproteinization with sulfosalicylic acid. Peptide amino acids were determined from filtrates obtained by deproteinization with sulfosalicylic acid. Peptide amino acids were determined from 4N methanesulfonic acid hydrolyzed plasma filtrates. Serum proteins were grossly separated by ion-exchange chromatography. Specific protein fractions were then hydrolyzed and analyzed for amino acid concentrations. Urea resulted in the reduction of plasma free amino acid levels due to a 30% decrease in EAA and a 16% decrease in NEAA. All EAA except MET and HIS were significantly depressed. Concentrations of amino acids in blood from the RBC were generally lower of amino acids in blood from the RBC were generally lower than from plasma for all amino acids, however, HIS and ASP were always more concentrated in the RBC. Urea significantly depressed RBC concentration of THR, VAL, MET, ILE, LEU AND PHE, however, most NEAA in the RBC were unaffected by dietary treatment. Exceptions were a large increase in GLY and decrease of ALA in the RBC of urea-fed animals. Net A/V differences across the hindlimb of soy-fed animals was positive for most plasma free amino acids. GLU, GLY and CYS accounted for all of the amino acid release. Urea feeding resulted in a small negative amino acid net A/V difference due to decreased uptakes and/or increased outputs by the hindlimb of several amino acids relative to soy-fed animals. The RBC hindlimb fluxes of several amino acids were altered by dietary treatment. The BCAA changed from large outputs in soy-fed animals so essentially a zero flux in urea-fed animals. In contrast, GLY changed from a large uptake in soy treatments to a large output when urea was fed. The free amino acid data from this experiment indicate that the urea-fed calves were subject to diets deficient in total protein and amino acids rather than specific amino acid differences. Negative A/V fluxes in urea-fed calves indicate muscle protein breakdown. Time effects were generally nonsignificant although a trend towards increased amino acid output across the hindlimb in urea-fed calves was apparent at 30 days. This implies that adaptation under these conditions was not occurring but rather a more severe deficiency state was encountered over time. These data also show further interrelationships between GLY and the neutral SCAA in altered nutritional states. Plasma peptides exhibited amino acid concentrations approximately 30% greater than whole blood free amino acids. HIS was significantly depressed and a tendency for lower levels of most other amino acids was noted in urea treatments. Peptide hindlimb exchanges were variable and nonsignificant with the exceptions of GLU, LYS, HIS and VAL uptakes in soy-fed animals and ILE in urea-fed animals. Peptides may, thus, be acting as a supplemental source of several amino acids to muscle tissue. Diet had little effect on amino acid composition of blood protein fraction I (primarily globulins) and fraction II (primarily albumin). Hindlimb amino acid exchanges of both fractions in soy-fed animals were inconsistent and non-significant. In contrast, the hindlimb of urea-fed animals removed large quantities of amino acids from both fractions with fractions II making the greatest contribution. Patterns of amino acid uptake closely resemble molar ratio within each fraction indicating whole protein uptake. These data show striking evidence of increased uptake of amino acids from blood proteins in calves fed urea purified diets. This may represent adaptation by muscle tissue of the animal to protein-deficient diets. / Ph. D.