Metabolic Adaptation to Experimentally Increased Glucose Demand in Ruminants

Thomas R. Overton, James K. Drackley, Cynthia J. Ottemann-Abbamonte, A. Denise Beaulieu, Jimmy H. Clark

Research output: Contribution to journalArticlepeer-review

Abstract

Four Dorset wethers were studied in a Latin square design with 72-h periods to determine the metabolic adaptations that occur in support of increased glucose demand in ruminants. Wethers injected at 8-h intervals with excipient or a total of .5, 1.0, or 2.0 g/d of phlorizin excreted an average of 0, 72.7, 97.9, and 98.5 g/d of glucose into the urine, respectively. Both acute (2 to 24 h after the first injection) and chronic (8-h intervals from 8 to 72 h after the first injection) adaptations of plasma variables to phlorizin treatment were assessed. Concentrations of plasma glucose decreased linearly with increasing phlorizin dose during the 1st 24 h of treatment and tended to decrease linearly with phlorizin dose during 8 to 72 h of treatment. Urea N tended to increase linearly during 2 to 24 h and increased linearly during 8 to 72 h. Nonesterified fatty acids increased linearly with phlorizin injection during the entire treatment period. β-Hydroxybutyrate increased quadratically with phlorizin injection during 2 to 24 h and tended to increase quadratically during 8 to 72 h. The ratio of insulin to glucagon tended to decrease linearly with phlorizin injection during the 1st 24 h but was unaffected from 8 to 72 h. Triiodothyronine, but not thyroxine, tended to decrease linearly with phlorizin injection during 8 to 72 h. Cortisol was not affected by treatment. Digestibilities of energy and N were not affected by treatment. Urinary energy excretion increased with phlorizin injection in proportion to the amounts of glucose excreted into the urine. These data indicate that phlorizin-treated wethers largely adapted to phlorizin treatment by 24 h after the first injection and are a suitable model for further investigations of hepatic adaptation to increased glucose demand in ruminants.

Original languageEnglish (US)
Pages (from-to)2938-2946
Number of pages9
JournalJournal of animal science
Volume76
Issue number11
DOIs
StatePublished - 1998

Keywords

  • Glucose
  • Metabolism
  • Phlorizin
  • Ruminants

ASJC Scopus subject areas

  • Food Science
  • Animal Science and Zoology
  • Genetics

Fingerprint

Dive into the research topics of 'Metabolic Adaptation to Experimentally Increased Glucose Demand in Ruminants'. Together they form a unique fingerprint.

Cite this