Glucose infusion response on some metabolic parameters in dairy cows during transition period

Abstract

Abstract. The aim of this study was to evaluate the effect of glucose tolerance test (GTT) on glucose, insulin, non-esterified fatty acids (NEFA) and β-Hydroxybutyrate (BHB) concentration in dairy cows during prepartum and postpartum period. Forty Two clinically healthy Holstein cows were enrolled in two high producing dairy farms in the Northeast Italy. All animals were divided into two equal groups on the basis of the farm of origin: Group A (farm located in Vicenza) and Group B (farm located in Padua). Body condition score (BCS) was determined for both groups. GTT was performed 7 ± 5 days before and 7 ± 5 days after calving. Blood samples were collected from each animal before (T0) and after the administration of glucose at different times. Plasma concentration of glucose, insulin, NEFA and BHB was evaluated. Application of two way analysis of variance (ANOVA) showed no significant effect of farm and a significant effect of transition period (prepartum and postpartum) on BCS for both groups. Multivariate analysis of variance (MANOVA) was applied to determine significant effects of infusion glucose time, transition period and farm on glucose, insulin, NEFA and BHB. No significant difference was observed between Groups A and B and a significant effect of transi tion period and glucose infusion was found on all parameters studied. Results confirm that glucose is an important direct controller of metabolic response in dairy cows during the transition period because of the inappropriate energetic supply that characterizing this physiological phases.

Changes in Thyroid Hormones Levels and Metabolism in Dairy Cows around Calving

“…The decrease in insulin levels found during post-partum is consistent with previous studies which reported high insulin levels before parturition, followed by a gradual decrease from 10 days before parturition remaining relatively low throughout lactation [28]. Lower glucose and insulin levels found during the post-partum period relative to the pre-partum period may be due to a decreased responsiveness of pancreatic β-cells to a state of hyperglycemia, caused by factors which inhibit the release of insulin [7].…”

“…A similar decrease of urea and K and the increase of AST levels found at post-partum in this study have been previously described by Fiore et al [9]. The AST increase could be associated to disorders involving the liver, including ketosis, even at subclinical levels [35].…”

“…Concentrations of blood metabolites including BHB, NEFA, glucose and insulin may provide some indication of postpartum disease risk and can be useful as a herd monitoring tool [7][8][9]. The positive correlation between circulating thyroid hormones concentrations and metabolic variables is well known in many animal species including cattle [10][11][12][13][14].…”

“…Thyroid hormones modulate metabolism in ruminants in which carbohydrates and lipids are the major constituents [6]. Transition dairy cows are often characterized by a decrease in serum glucose level and an increase of nonesterifi ed fatty acids (NEFA) and β-hydroxybutyrate (BHB) serum concentrations, suggesting the diffi culty of dairy cows to cope with the energy demand which characterizes the transition period [7].…”

Relationships among circulating metabolic biomarkers in healthy high-producing holstein dairy cows in different physiological states

“…There are several studies on metabolic profile during the periods of the productive life of the cows such as transition and lactation periods (Ghanem et al, 2012;Piccione et al, 2012;Fiore et al, 2014). Based on author's knowledge, there is little information regarding the circulating metabolic profile in different physiological states of dairy cows in a comprehensive study.…”