title: Proton nuclear magnetic resonance spectroscopy based investigation on propylene glycol toxicosis in a Holstein cow.
abstract: BACKGROUND
  It is unknown which metabolites are responsible for propylene glycol (PG)-induced toxicosis, and a better understanding of the underlying mechanisms explaining incidences of abnormal behaviour of dairy cows fed PG is therefore needed.
  
  
  METHODS
  The study included three cows of which one developed PG toxicosis. In order to investigate how the metabolism of PG differed in the cow developing toxicosis, proton nuclear magnetic resonance (NMR) spectroscopy was applied on ruminal fluids and blood plasma samples obtained before and after feeding with PG.
  
  
  RESULTS
  PG toxicosis was characterized by dyspnea and ruminal atony upon intake of concentrate containing PG. The oxygen saturation of arterial blood haemoglobin and the oxygen pressure in arterial blood decreased along with the appearance of the clinical symptoms. NMR revealed differences in plasma and ruminal content of several metabolites between the cow responding abnormally to PG and the two control cows.
  
  
  CONCLUSIONS
  It is concluded that PG-toxicosis is likely caused by pulmonary vasoconstriction, but no unusual metabolites directly related to induction of this condition could be detected in the plasma or the ruminal fluid.
authors.affiliation: Department of Food Science, Faculty of Agricultural Sciences, Aarhus University, PO Box 102, DK-5792 Arslev, Denmark. HanneC.Bertram@agrsci.dk
authors.forename: Hanne Christine
authors.initials: HC
authors.lastname: Bertram
authors.forename: Bent Ole
authors.initials: BO
authors.lastname: Petersen
authors.forename: Jens Ø
authors.initials: JØ
authors.lastname: Duus
authors.forename: Mogens
authors.initials: M
authors.lastname: Larsen
authors.forename: Birgitte-Marie L
authors.initials: BM
authors.lastname: Raun
authors.forename: Niels Bastian
authors.initials: NB
authors.lastname: Kristensen
mesh_terms: D000818:Animals; D001774:Blood Chemical Analysis; D002417:Cattle; D002418:Cattle Diseases / Q000139:chemically induced* / Q000378:metabolism; D005260:Female; D008168:Lung / Q000098:blood supply; D019906:Nuclear Magnetic Resonance, Biomolecular; D010100:Oxygen / Q000097:blood; D019946:Propylene Glycol / Q000009:adverse effects* / Q000032:analysis* / Q000378:metabolism; D012417:Rumen / Q000378:metabolism; D014661:Vasoconstriction / Q000187:drug effects*
chemical_list: D019946:Propylene Glycol; D010100:Oxygen