@article {88195,
	title = {Efficiency of superovulation and in vivo embryo production in eFSH-treated donor mares after estrus synchronization with progesterone and estradiol-17beta},
	journal = {Theriogenology},
	volume = {72},
	year = {2009},
	month = {2009 Jul 15},
	pages = {169-78},
	abstract = {Reliable methods of regulating estrus and stimulating superovulations in equine embryo transfer programs are desirable. Our objectives were to investigate the efficacy of a progesterone and estradiol-17beta (P\&E) estrus synchronization regimen in mares with and without subsequent equine follicle-stimulating hormone (eFSH) treatment and to examine the effects of eFSH on folliculogenesis and embryo production. Cycling mares were treated with P\&E daily for 10 d. On the final P\&E treatment day, prostaglandin F(2alpha) was administered, and mares were randomly assigned to one of two treatment groups (n=20 mares/group). In both groups, mares were examined daily by transrectal ultrasonography. In the eFSH group, twice-daily eFSH treatments were initiated at follicle diameter 20 to 25 mm and ceased at follicle > or =35 mm; human chorionic gonadotrophin (hCG) was administered after 36 h. In the control group, eFSH treatments were not given, but hCG was administered at follicle > or =35 mm. Mares were inseminated with fresh semen, and embryo recovery attempts were performed 8 d postovulation. Synchrony of ovulations within each group appeared to be similar. Six mares in the eFSH group failed to ovulate. The eFSH treatment resulted in higher (P<0.05) numbers of preovulatory follicles and ovulations; however, embryo recovery rate did not increase (eFSH 1.0+/-0.4 vs. control 0.95+/-0.1 embryos/recovery attempt), and embryo per ovulation rate was significantly lower (36\% vs. 73\%). The eFSH-treated mares had significantly higher frequency of nonovulatory follicles (28\% vs. 0) and higher periovulatory serum concentrations of estradiol-17beta. Based on our findings, combined P\&E and eFSH regimens cannot be recommended for cycling donor mares.},
	keywords = {Animals, Chorionic Gonadotropin, Embryo Transfer, Estradiol, Estrus Synchronization, Female, Follicle Stimulating Hormone, Horses, Insemination, Artificial, Ovarian Follicle, Ovulation, Progesterone, Superovulation, Tissue and Organ Harvesting, Ultrasonography},
	issn = {1879-3231},
	doi = {10.1016/j.theriogenology.2009.02.011},
	author = {Raz, T and Card, C}
}
