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


     

J. Anim Sci. 1972. 34:88-92.
© 1972 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 Mauer, R. E.
Right arrow Articles by White, W. F.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Mauer, R. E.
Right arrow Articles by White, W. F.

Levels of Luteinizing Hormone in Sera of Ewes near the Time of Estrus as Determined by Radioimmunoassay1

R. E. Mauer, P. Revenal2, E. S. Johnson, R. H. Moyer, A. Hirata and W. F. White

Abbott Laboratories,3 North Chicago, Illinois 60064

Abstract

Serum LH levels were measured by radioimmunoassay in ewes treated with progesterone-dimethylpolysiloxane implants. During the early anestrous season (March) the LH surge occurred 42 hr. to more than 68 hr. after removal of the implant. Behavioral estrus was detected 2 to 12 hr. before the LH peak. The typical peak commenced 48 to 50 hr. after implant removal or 8 hr. after onset of estrus. LH rose within a 2-hr, period to levels in excess of 100 ng/ml of serum where they remained for 2 to A hours. Within 8 hr. after the start of the peak, levels of LH in serum had returned to base line. During the estrous season the LH peak began 34 hr. after removal of the implants and estrus was detected 8 hr. after the LH peak. PMS treatment did not significantly affect the time of the LH peak. Increasing the progesterone dosage appeared to increase the interval from removal of the implants to detection of the LH peak. PMS injection at implant removal in ewes with the higher progesterone dosage may have shortened the interval from removal of the implant to the LH peak. The LH peak was not detected in ewes treated with three implants and injected with 500 IU HCG 32 hr. after implant removal.

Footnotes

1 The authors wish to express their appreciation to Dr. P. Dziuk for reviewing the manuscript.

2 Present address: Northfolk General Hospital, Northfolk, Virginia.

3 Agriculture and Veterinary Products Division.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1972 by the American Society of Animal Science.