Development of fertility programs to achieve high 21-day pregnancy rates in high-producing dairy cows
| Autor: | V.G. Santos, Paul M. Fricke, Milo C. Wiltbank, P.D. Carvalho, Julio O. Giordano |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
0301 basic medicine
Pregnancy Rate media_common.quotation_subject Fertility Biology 03 medical and health sciences Animal science Food Animals Pregnancy medicine Animals Lactation Small Animals Insemination Artificial Dairy cattle media_common Equine 0402 animal and dairy science 04 agricultural and veterinary sciences medicine.disease 040201 dairy & animal science 030104 developmental biology Pregnancy Animal Cattle Female Animal Science and Zoology Estrus Synchronization |
| Zdroj: | Theriogenology. 114:165-172 |
| ISSN: | 0093-691X |
| DOI: | 10.1016/j.theriogenology.2018.03.037 |
| Popis: | Our objective is to overview the research that lead to the development of fertility programs for high-producing lactating dairy cows using only GnRH and Prostaglandin F2α (PGF2α), such as Ovsynch with a focus on the role of progesterone in fertility. A key factor affecting fertility to timed-AI is the response to each hormonal treatment of the Ovsynch protocol. Although not required for fertility, cows ovulating to the first GnRH treatment of the Ovsynch protocol (G1) have greater P/AI than cows failing to ovulate. The association between progesterone concentrations at each treatment during the Ovsynch protocol and fertility is reviewed, and data from 7792 cows from 14 studies are presented. Overall, medium P4 (between 0.5 and 6 ng/mL) at G1, high P4 concentrations (>1.0 ng/mL) at the PGF2α, and low P4 concentrations ( |
| Databáze: | OpenAIRE |
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