title: Validation of different measures of insulin sensitivity of glucose metabolism in dairy cows using the hyperinsulinemic euglycemic clamp test as the gold standard.
abstract: The aim of the present research was to compare different measures of insulin sensitivity in dairy cows at the end of the dry period. To do so, 10 clinically healthy dairy cows with a varying body condition score were selected. By performing hyperinsulinemic euglycemic clamp (HEC) tests, we previously demonstrated a negative association between the insulin sensitivity and insulin responsiveness of glucose metabolism and the body condition score of these animals. In the same animals, other measures of insulin sensitivity were determined and the correlation with the HEC test, which is considered as the gold standard, was calculated. Measures derived from the intravenous glucose tolerance test (IVGTT) are based on the disappearance of glucose after an intravenous glucose bolus. Glucose concentrations during the IVGTT were used to calculate the area under the curve of glucose and the clearance rate of glucose. In addition, glucose and insulin data from the IVGTT were fitted in the minimal model to derive the insulin sensitivity parameter, Si. Based on blood samples taken before the start of the IVGTT, basal concentrations of glucose, insulin, NEFA, and β-hydroxybutyrate were determined and used to calculate surrogate indices for insulin sensitivity, such as the homeostasis model of insulin resistance, the quantitative insulin sensitivity check index, the revised quantitative insulin sensitivity check index and the revised quantitative insulin sensitivity check index including β-hydroxybutyrate. Correlation analysis revealed no association between the results obtained by the HEC test and any of the surrogate indices for insulin sensitivity. For the measures derived from the IVGTT, the area under the curve for the first 60 min of the test and the Si derived from the minimal model demonstrated good correlation with the gold standard.
authors: Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium. Electronic address: jenne.dekoster@ugent.be.
authors: J
authors: J
authors: De Koster
authors: Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
authors: M
authors: M
authors: Hostens
authors: Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
authors: K
authors: K
authors: Hermans
authors: Department of Morphology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
authors: W
authors: W
authors: Van den Broeck
authors: Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
authors: G
authors: G
authors: Opsomer
mesh_terms: D000818:Animals; D001786:Blood Glucose; D001823:Body Composition; D002417:Cattle / Q000097:blood / Q000502:physiology*; D005260:Female; D005947:Glucose / Q000378:metabolism*; D015309:Glucose Clamp Technique / Q000662:veterinary*; D005951:Glucose Tolerance Test; D007333:Insulin Resistance / Q000502:physiology*; D015203:Reproducibility of Results
chemical_list: D001786:Blood Glucose; D005947:Glucose
keywords: Dairy cow; Hyperinsulinemic euglycemic clamp test; Insulin resistance; Insulin sensitivity; Measures