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Blood Sampling and Hormone Measurement for Determining the Stage in the Ovarian Cycle in Marmosets
Published on: July 5, 2024
Time of ovulation in nulliparous and multiparous goats
J Simões1, G Baril, J C Almeida
11CECAV, University of Trás-os-Montes e Alto Douro, Apartado 1013, 5001-801 Vila Real, Portugal.
Animal : an International Journal of Animal Bioscience
|March 27, 2012
Summary
Nulliparous goats ovulate earlier than multiparous goats, with differences in ovulation timing and number influenced by parity and estrus type. Further research is needed to understand these reproductive cycle variations.
Area of Science:
- Reproductive biology
- Veterinary science
- Animal science
Background:
- Understanding ovulation timing is crucial for reproductive management in goats.
- Parity and estrus type can influence ovulation dynamics.
Purpose of the Study:
- To characterize ovulation time in relation to ovulation number in nulliparous and multiparous Serrana goats.
- To compare ovulation timing after induced and natural estrus during the breeding season.
Main Methods:
- Estrus synchronization using prostaglandin and detection with vasectomized bucks.
- Luteinizing hormone (LH) peak determination via blood sampling.
- Transrectal ovarian ultrasound scanning for ovulation detection.
Main Results:
- Nulliparous goats had a shorter onset of estrus to LH peak interval than multiparous goats.
- The LH peak to first ovulation interval was longer after natural estrus compared to induced estrus.
- Nulliparous goats, predominantly monovular, ovulated earlier than multiparous goats, which were predominantly polyovular.
Conclusions:
- Significant differences exist in ovulation number and timing between nulliparous and multiparous goats.
- Parity and estrus type are key factors influencing ovulation patterns in Serrana goats.
- Further investigation is required to elucidate the regulatory mechanisms of monovular and polyovular estrous cycles in goats.
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