Relationships of Oocyte Quality and IGF-I in Follicular Fluid During the Estrual Period in Cattle and Effects of Pre-Estrual Progestins
| Autor: | J. M. Grizzle, R. R. Maurer, T. Wise |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
Estrous cycle
endocrine system medicine.medical_specialty In vitro fertilisation urogenital system medicine.medical_treatment Artificial insemination media_common.quotation_subject Biology Oocyte Follicular fluid Endocrinology medicine.anatomical_structure Internal medicine Follicular phase medicine Corpus luteum Ovulation hormones hormone substitutes and hormone antagonists reproductive and urinary physiology media_common |
| Zdroj: | Signaling Mechanisms and Gene Expression in the Ovary ISBN: 9781461278306 |
| Popis: | Two techniques are predominantly utilized to synchronize beef animals to estrus for artificial insemination or in vitro fertilization of oocytes: (a) prostaglandin-induced corpus luteum regression, which results in estrus and ovulation in 48-60 h, and (b) implanting/injecting progestins for5–20 days, which upon removal of silastic implants and clearance of progestin, results in estrus and ovulation. Both techniques produce comparable results in reference to estrus and ovulation, but conception and fertility are generally reduced with progestins (1, 2, 3). Follicular progesterone concentrations and the time when progesterone concentrations increase and fall are important in the maturation and quality of oocytes (4, 5). Insulin-like growth factor I (IGF-I) may have a role in regulating follicular progesterone concentrations (6, 7, 8, 9) and subsequent oocyte quality. The objectives of this study were to (a) elucidate possible differences in oocyte quality between prostaglandin-and progestin-synchronized estrus in heifers and (b) establish relationship of follicular IGF-1 to oocyte quality, follicular development, and progestin effects as influenced by treatments. |
| Databáze: | OpenAIRE |
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