rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    non sort: The
    title: pathophysiologic effects of the alkaloids of tall fescue (Festuca arundinaceae, Schreb,) in cattle
  name:
    name part: Davis, Charmille Bridges
    role:
      role term: creator
  name:
    name part: Bailey, E. M.
    role:
      role term: degree committee member.
  name:
    name part: Camp, B. J.
    role:
      role term: degree supervisor.
  name:
    name part: Corrier, D. E.
    role:
      role term: degree committee member.
  name:
    name part: Jenkins, W. L.
    role:
      role term: degree committee member.
  name:
    name part: Texas A & M University
    role:
      role term: degree granting institution.
  type of resource: text
  genre: bibliography
  genre: Academic theses
  origin info:
    place:
      place term: xx
    date issued: 1983
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: print
    extent: x, 98 leaves : illustrations ; 29 cm
  abstract: Halostachine, a sympathomimetic amine present in tall fescue, was evaluated as a possible contributing agent in the development of fescue toxicity in cattle. A gas chromatographic method was developed for the analysis of halostachine (N-methyl phenylethanolamine) in tall fescue. The recovery of halostachine from spiked plant extract was 66.7 (+OR-) 2%. Halostachine was found to complex with N-formyl and N-acetyl loline in plant extracts. The ratio of free versus conjugated halostachine fluctuated with the concentration of loline alkaloids in the plant. The binding of halostachine to the carbonyl groups of the loline alkaloids was prevented by the addition of hydroxylamine (NH(,2)OH) as NH(,2)OH reacts with the carbonyl groups to form oximes. Recovery of halostachine was not improved, as the oximes were not stable under the pH changes required by the extraction process. The levels of halostachine in a test pasture of Kenhy tall fescue were correlated with the occurrence of signs of fescue toxicity in cattle grazing the pasture. Halostachine content increased prior to an occurrence of an episode of toxicity in December, 1981. The toxicity was also correlated with a period of sustained cold weather. An in vivo study of cattle of the response of blood pressure and coronary band temperature to I.V. administration of racemic halostachine showed that racemic halostachine produced pressor effects (42 mm Hg/0.1 mg/kg) and peripheral vasoconstriction. The pressor effects of halostachine were prevented by an alpha-receptor blocker. Furthermore, tachyphylaxis was not observed. A coronary band temperature decrease also was observed in response to halostachine administration. The administration of an MAO-A inhibitor, norharmane, did not potentiate the effects of halostachine in vivo at a 1 mg/kg dose. An in vitro assay established that halostachine was a substrate for monoamine oxidase (MAO). The K(,m) and V(,max) for beef liver MAO using halostachine as a substrate were 132 (mu)…
  note: "Major subject: "Veterinary Toxicology."
  note: Typescript (photocopy).
  note: Vita.
  note: Ph. D. in Philosophy Texas A & M University 1983
  note: Includes bibliographical references (leaves 92-97).
  subject:
    topic: Cattle
    topic: Diseases
  subject:
    topic: Fescue foot
  subject:
    topic: Livestock poisoning plants
  subject:
    topic: Veterinary toxicology
  subject:
    topic: Veterinary Toxicology
  identifier: http://proxy.library.tamu.edu/login
  identifier: https://hdl.handle.net/1969.1/DISSERTATIONS-524967
  related item:
    location:
      url: http://proxy.library.tamu.edu/login
  related item:
    location:
      url: https://hdl.handle.net/1969.1/DISSERTATIONS-524967
  record info:
    record content source: TXA
    record creation date: 840501
    record change date: 20220103135142.0
    record identifier: in00000523047
    language of cataloging:
      language term: eng