J. Anim Sci.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J. Anim Sci. 1973. 37:718-721.
© 1973 American Society of Animal Science
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 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 Google Scholar
Google Scholar
Right arrow Articles by Rigor, E. M.
Right arrow Articles by Hansel, W.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Rigor, E. M.
Right arrow Articles by Hansel, W.

In Vitro Progesterone Synthesis by Corpora Lutea of Hysterectomized Ewes after In Vivo Stimulation with Luteinizing Hormone1

E. M. Rigor2 and W. Hansel3

Cornell University,,4 Ithaca, New York 14850

Abstract

Thirty-One mature ewes of mixed breeding were hysterectomized on day 8 of the cycle (day 0=day of heat) and assigned at random to a 2 µ 2 µ 3 factorial experiment. Treatments consisted of 0 or 0.5 mg bovine LH per day for 6 days beginning on the 15th (23-day-old CL) or 30th (38-day-old CL) day after hysterectomy. Ewes were slaughtered 1, 10 or 20 days after LH withdrawal and the corpora lutea incubated in vitro and extracted for progesterone. New ovulations were induced in five of 13 ewes given LH. The 23-day-old CL were significantly (P<.01) heavier than the 38-day-old CL. There was a significant interaction (P<.05) of interval to incubation with age of CL. Total progesterone was greater (P<.10) in the 23-day-old CL than in the 38-day-old CL. Net progesterone synthesis was significantly (P<.05) greater in the 38-day- than 23-day-old CL. There was a significant interaction (P<.05) of age of CL with LH or saline injection and interval to incubation. There was an apparent "depression of synthesis" or net loss of progesterone, in response to LH added in vitro, by the 23-day-old CL removed 1 day after 6 days of LH treatment in vivo. The previous administration of LH in vivo did not cause a shortening of the life span of the CL.

Footnotes

1 This investigation was suported in part by a Public Health Service International Postdoctoral Research Fellowship. (No. 1 F05 TW 1709-01).

2 Present address: University of the Philippines College of Agriculture, College, Laguna, Philippines.

3 The authors gratefully acknowledge the generous gift of bovine luteinizing hormone from the Endocrinology Study Section, NIH, Bethesda, Maryland.

4 Department of Animal Science and Division of Biological Sciences.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1973 by the American Society of Animal Science.