Roles of hCG in Advancing Follicular Growth to Ovulation after Concurrent Injections of PGF2α and GnRH in Postpubertal Holstein Heifers Bearing a CL
Joint Authors
Johnson, Ricky
Cuadra, Evelin J.
Mason, Melissa
Jung, Yoonsung
Bennett, William A.
Njiti, Victor
Source
Veterinary Medicine International
Issue
Vol. 2010, Issue 2010 (31 Dec. 2010), pp.1-7, 7 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2010-12-01
Country of Publication
Egypt
No. of Pages
7
Main Subjects
Abstract EN
A study was conducted to test the hypothesis that injecting Gonadotropin-releasing hormone (GnRH) concurrently with Prostaglandin F2 alpha (PGF2α) followed by an injection of human Chorionic Gonadotropin (hCG), would advance follicular growth to ovulation in Holstein heifers bearing a corpus luteum (CL).
After manual examination of the CL, group 1 (PGF; n=12) received an injection of PGF2α (25 mg, im).
Group 2 (PGF + GnRH; n=13) received an injection of GnRH (100 μg, im) immediately after an injection of PGF2α.
Group 3 (PGF + GnRH + hCG; n=12) received concurrent injections of PGF2α and GnRH followed with hCG (1500 IU, im) two days later.
Follicular size and day of ovulation were monitored by daily ultrasonographic examination from days 1 to 10.
Blood was collected on days-7, 0 (PGF2α administration), 2, and 7.
Progesterone was not different (P>.05) on days-7, 0, and 2 between the experimental groups.
However, it was higher (P<.005) in the PGF + GnRH + hCG group on day 7 compared to PGF + GnRH heifers, but not significantly higher than the PGF.
Additionally, heifers in the PGF + GnRH + hCG group ovulated earlier (P<.05) than heifers in the PGF + GnRH and the PGF group.
This data indicates that hCG advances follicular growth to ovulation in spite of high levels of progesterone when injected 48 h after concurrent treatments of GnRH and PGF2α on heifers bearing a CL.
American Psychological Association (APA)
Johnson, Ricky& Bennett, William A.& Cuadra, Evelin J.& Njiti, Victor& Jung, Yoonsung& Mason, Melissa. 2010. Roles of hCG in Advancing Follicular Growth to Ovulation after Concurrent Injections of PGF2α and GnRH in Postpubertal Holstein Heifers Bearing a CL. Veterinary Medicine International،Vol. 2010, no. 2010, pp.1-7.
https://search.emarefa.net/detail/BIM-468665
Modern Language Association (MLA)
Johnson, Ricky…[et al.]. Roles of hCG in Advancing Follicular Growth to Ovulation after Concurrent Injections of PGF2α and GnRH in Postpubertal Holstein Heifers Bearing a CL. Veterinary Medicine International No. 2010 (2010), pp.1-7.
https://search.emarefa.net/detail/BIM-468665
American Medical Association (AMA)
Johnson, Ricky& Bennett, William A.& Cuadra, Evelin J.& Njiti, Victor& Jung, Yoonsung& Mason, Melissa. Roles of hCG in Advancing Follicular Growth to Ovulation after Concurrent Injections of PGF2α and GnRH in Postpubertal Holstein Heifers Bearing a CL. Veterinary Medicine International. 2010. Vol. 2010, no. 2010, pp.1-7.
https://search.emarefa.net/detail/BIM-468665
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-468665