HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Interpretive Summary Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Smith, K. L. Articles by Overton, T. R. Search for Related Content PubMed PubMed Citation Articles by Smith, K. L. Articles by Overton, T. R.

Prepartum 2,4-Thiazolidinedione Alters Metabolic Dynamics and Dry Matter Intake of Dairy Cows

Department of Animal Science, Cornell University, Ithaca, NY 14853

³ Corresponding author: tro2{at}cornell.edu

Thiazolidinediones (TZD) are potent, synthetic ligands for peroxisome proliferator activated receptor-gamma (PPAR-) that reduce plasma nonesterified fatty acids (NEFA) and potentiate the action of insulin in peripheral tissues of several species. Holstein cows (n = 9) entering their second or greater lactation were used to determine whether late prepartum administration of TZD would affect periparturient metabolism and milk production. Cows were limit-fed a total mixed ration (TMR) during the prepartum period to provide no more than 130% of predicted energy requirements. During the postpartum period cows were fed a common TMR for ad libitum intake. Cows were administered either 2,4-TZD (4.0 mg/kg of body weight) or saline (control) by intrajugular infusion once daily from 25 d before expected parturition until parturition. Plasma samples were collected daily from 26 d before expected parturition through 7 d postpartum. Plasma NEFA concentrations decreased during the prepartum period (d –21 to –1; 70 vs. 83 ± 4 µEq/L) and tended to be decreased during the peripartum period (d –7 to d +7; 113 vs. 205 ± 32 µEq/L) due to prepartum TZD administration. Plasma concentrations of glucose were not affected by treatment; however, plasma ß-hydroxybutyrate concentrations decreased in TZD-treated cows (8.6 vs. 10.7 ± 1.7 mg/dL) as parturition approached, and plasma insulin concentrations increased during the peripartum period (0.65 vs. 0.38 ± 0.07 ng/mL). Postpartum liver triglyceride and glycogen content was not affected by treatment. Prepartum TZD administration tended to increase dry matter intake during the peripartum and postpartum periods (16.6 vs. 14.6 ± 0.8 kg/d and 20.0 vs. 17.2 ± 1.2 kg/d, respectively). Milk yield for the first 30 d postpartum and milk composition measured on d 8 postpartum were not affected by treatment. There was no effect of prepartum TZD administration on insulin-dependent glucose utilization assessed using insulin challenge during either the prepartum or postpartum periods. These results suggest that administration of TZD during the late prepartum period has the potential to improve metabolic health and DMI of periparturient dairy cows and warrants further investigation.

Key Words: transition cow • thiazolidinedione • peroxisome proliferator activated receptor-gamma