Biol Reprod Lalor Postdoctoral Fellowships -- Application Deadline January 15, 2009
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Fitzgerald, B. P.
Right arrow Articles by Loy, R. G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Fitzgerald, B. P.
Right arrow Articles by Loy, R. G.
Agricola
Right arrow Articles by Fitzgerald, B. P.
Right arrow Articles by Loy, R. G.

Biology of Reproduction, Vol 33, 316-323, Copyright © 1985 by Society for the Study of Reproduction

ARTICLES

Changes in patterns of luteinizing hormone secretion before and after the first ovulation in the postpartum mare

BP Fitzgerald, H I'Anson, SJ Legan and RG Loy

To determine whether luteinizing hormone (LH) secretion during the first estrous cycle postpartum is characterized by pulsatile release, circulating LH concentrations were measured in 8 postpartum mares, 4 of which had been treated with 150 mg progesterone and 10 mg estradiol daily for 20 days after foaling to delay ovulation. Blood samples were collected every 15 min for 8 h on 4 occasions: 3 times during the follicular phase (Days 2-4, 5-7, and 8-11 after either foaling or end of steroid treatment), and once during the luteal phase (Days 5-8 after ovulation). Ovulation occurred in 4 mares 13.2 +/- 0.6 days postpartum and in 3 of 4 mares 12.0 +/- 1.1 days post-treatment. Before ovulation, low-amplitude LH pulses (approximately 1 ng/ml) were observed in 3 mares; such LH pulses occurred irregularly (1-2/8 h) and were unrelated to mean circulating LH levels, which gradually increased from less than 1 ng/ml at foaling or end of steroid treatment to maximum levels (12.3 ng/ml) within 48 h after ovulation. In contrast, 1-3 high-amplitude LH pulses (3.7 +/- 0.7 ng/ml) were observed in 6 of 7 mares during an 8-h period of the luteal phase. The results suggest that in postpartum mares LH release is pulsatile during the luteal phase of the estrous cycle, whereas before ovulation LH pulses cannot be readily identified.


This article has been cited by other articles:


Home page
 ReproductionHome page
O J Ginther, M A Beg, E L Gastal, M O Gastal, A R Baerwald, and R A Pierson
Systemic concentrations of hormones during the development of follicular waves in mares and women: a comparative study
Reproduction, September 1, 2005; 130(3): 379 - 388.
[Abstract] [Full Text] [PDF]

Home page
 Biol. Reprod.Home page
T.J. Acosta, M.A. Beg, and O.J. Ginther
Aberrant Blood Flow Area and Plasma Gonadotropin Concentrations During the Development of Dominant-Sized Transitional Anovulatory Follicles in Mares
Biol Reprod, August 1, 2004; 71(2): 637 - 642.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1985 by the Society for the Study of Reproduction.