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Testosterone secretion during early pregnancy in the goat
1Department of Veterinary Preclinical Sciences, University of Liverpool Veterinary Field Station, Leahurst, Chester High Road, Neston, South Wirral, Cheshire, L64 7TE, United Kingdom.
Theriogenology
|August 1, 1989
Summary
In goats, increased testosterone levels signal the end of the estrous cycle and initiate luteolysis. Pregnancy prevents this testosterone surge, indicating its role in maternal recognition of pregnancy.
Area of Science:
- Reproductive endocrinology
- Animal physiology
Background:
- Luteolysis, the regression of the corpus luteum, is a critical event in the estrous cycle.
- Hormonal regulation of reproductive cycles and pregnancy recognition is complex and species-specific.
Purpose of the Study:
- To investigate the role of testosterone in luteolysis during the estrous cycle in goats.
- To determine if testosterone concentrations change during early pregnancy in goats and if this relates to luteal maintenance.
Main Methods:
- Peripheral blood samples were collected from goats throughout the estrous cycle and early pregnancy.
- Concentrations of testosterone were measured using validated assays.
Main Results:
- Testosterone levels increased significantly on Days 12 and 13 of the estrous cycle, coinciding with the onset of luteolysis.
- In pregnant goats, no increase in peripheral testosterone was observed between Days 10 and 18 post-mating, and luteal regression was inhibited.
Conclusions:
- Testosterone appears to be a key hormone required for initiating luteolysis in goats.
- The absence of a testosterone surge during early pregnancy may be a mechanism for maternal recognition of pregnancy, preventing luteal regression.
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