Effect of expression of estrus and treatment with GnRH on pregnancies per AI in beef cattle synchronized with an estradiol/progesterone-based protocol
| Autor: | G.A. Bo, A. Tribulo, Alejo Menchaca, R. Tribulo, Andrés V. Cedeño, Reuben J. Mapletoft, Salvador Andrada, Rodrigo Cuervo |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
endocrine system
medicine.medical_treatment media_common.quotation_subject Gonadotropin-releasing hormone Beef cattle Dinoprost Andrology Gonadotropin-Releasing Hormone chemistry.chemical_compound Food Animals Estrus Pregnancy medicine Animals Small Animals Ovulation Insemination Artificial Progesterone media_common Estrous cycle Estradiol Equine business.industry Artificial insemination Estradiol cypionate medicine.disease chemistry Estradiol benzoate Animal Science and Zoology Cattle Female business Estrus Synchronization hormones hormone substitutes and hormone antagonists medicine.drug |
| Zdroj: | Theriogenology. 161 |
| ISSN: | 1879-3231 |
| Popis: | Three experiments evaluated the effects of expression of estrus and gonadotropin releasing hormone (GnRH) treatment on pregnancies per AI (P/AI) in beef cattle that were treated with an estradiol/progesterone (P4)-based protocol for fixed-time artificial insemination (FTAI). In Experiment 1, 20 non-lactating beef cows were treated with 2 mg estradiol benzoate (EB) and an intravaginal device containing 0.5 g of P4. Seven days later, P4 devices were removed and all cows received prostaglandin F2 alpha (PGF2α) and 0.5 mg estradiol cypionate (ECP). Estrus was detected using tail paint and cows that did not show estrus by 48 h after P4 device removal were randomized to receive GnRH or no treatment. Ovulation, as determined by ultrasonography, occurred earlier in cows that showed estrus (68.0 ± 2.5 h) than in cows that did not (82.0 ± 2.1 h, P |
| Databáze: | OpenAIRE |
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