SINCRONIZAÇÃO DE ESTRO COM PROSTAGLANDINA F2? versus PROGESTÁGENO ASSOCIADO À GONADOTROFINA CORIÔNICA EQUINA (eCG) EM OVELHAS SANTA INÊS NO DISTRITO FEDERAL, BRASIL

The aim of this study was to compare two protocols of estrus synchronization in Santa Ines ewes. Thirty-eight ewes were randomly divided into two groups of estrus synchronization: protocol PGF2? (two doses of 0.530 mg of PGF2?, nine days apart) and protocol MAP+eCG (intravaginal sponge impregnated with medroxyprogesterone acetate, for 12 days, and then an injection of 250 IU of eCG). The experiment was in a cross-over design, two estrous cycles apart. On the final day of protocol, a transrectal ultrasound examination was carried out to measure the size of the largest and second largest ovarian follicles and on day 7 of estrous cycle blood was collected to measure serum P4 concentration. Laparoscopy was carried out on day 11 after the end of protocols to count corpora lutea. Synchronization rate, size of largest and second largest ovarian follicles, interval between the end of the protocol to estrus and ovulation rate did not differ between protocols. Ewes synchronized with MAP+eCG had greater serum P4 concentrations than ewes synchronized with PGF2? (3.9 and 2.8 ng/mL, respectively, P KEYWORDS: Follicle size, serum progesterone, sheep, synchronization rate.