Theriogenology
Volume 74, Issue 3 , Pages 384-392, August 2010

Stimulation of pulses of 13,14-dihydro-15-keto-PGF2α (PGFM) with estradiol-17β and changes in circulating progesterone concentrations within a PGFM pulse in heifers

  • O.J. Ginther

      Affiliations

    • Eutheria Foundation, Cross Plains, Wisconsin 53528, USA
    • Department of Pathobiological Sciences, University of Wisconsin, Madison, Wisconsin 53706, USA
    • Corresponding Author InformationCorresponding author. Tel.: +1 608 798 3777; fax: +1 608 798 4910
  • ,
  • H.K. Shrestha

      Affiliations

    • Eutheria Foundation, Cross Plains, Wisconsin 53528, USA
  • ,
  • M.J. Fuenzalida

      Affiliations

    • Eutheria Foundation, Cross Plains, Wisconsin 53528, USA
  • ,
  • S. Imam

      Affiliations

    • Eutheria Foundation, Cross Plains, Wisconsin 53528, USA
  • ,
  • M.A. Beg

      Affiliations

    • Department of Pathobiological Sciences, University of Wisconsin, Madison, Wisconsin 53706, USA

Received 19 January 2010; received in revised form 19 February 2010; accepted 24 February 2010. published online 23 April 2010.

Abstract 

A single physiologic dose (0.1 mg) of estradiol-17β in sesame-oil vehicle or vehicle alone (n = 8) was given to heifers on day 14 after ovulation to study the effect on circulating 13-14-dihydro-15-keto-PGF2α (PGFM), PGFM pulses, and changes in progesterone concentrations within a PGFM pulse. Blood samples were collected hourly for 16 h after treatment. The estradiol group had a greater mean concentration of PGFM, greater number of heifers with PGFM pulses and number of pulses/heifer, and greater prominence of the PGFM pulses. Changes in progesterone concentrations were not detected during the 16 h sampling session in the vehicle group, indicating that the heifers were in preluteolysis. Progesterone decreased after 12 h in the estradiol group, indicating a luteolytic effect of the estradiol-induced PGF secretion as represented by PGFM concentrations. Intrapulse changes in progesterone were detected during a PGFM pulse in the estradiol group (P < 0.006), but not in the vehicle group. Progesterone increased (P < 0.01) between Hours −2 and −1 of an estradiol-induced PGFM pulse (Hour 0 = peak of pulse), decreased (P < 0.004) between Hours −1 and 0, and increased (P < 0.01) or rebounded between Hours 0 and 1. Results were compatible with previous reports of a role for estradiol in the induction of PGFM pulses in cattle and demonstrated intrapulse changes in progesterone concentrations during an induced PGFM pulse.

Keywords: Estradiol, Luteolysis, PGF2α, PGFM pulses, Progesterone

To access this article, please choose from the options below

Login to an existing account or Register a new account.

  • Purchase this article for 15.00 USD (You must login/register to purchase this article)

    Online access for 24 hours. The PDF version can be downloaded as your permanent record.

  • Subscribe to this title

    Get unlimited online access to this article and all other articles in this title 24/7 for one year.

  • Claim access now

    For current subscribers with Society Membership or Account Number.

  • Visit SciVerse ScienceDirect to see if you have access via your institution.
 

PII: S0093-691X(10)00136-6

doi:10.1016/j.theriogenology.2010.02.021

Theriogenology
Volume 74, Issue 3 , Pages 384-392, August 2010