Equine Embryo Transfer

Contents1. IntroductionGeneral Introduction (i.e. what is ET) Advantages and uses of embryo transferChanges in the ET IndustryBreed regulations (include a Table of most major breeds; ET, frozen embryos, etc.)Per cycle ET Success = Embryo Collection Rate (50-60%) x Embryo Transfer Pregnancy Rate (70-80%)Goals of the Manual2. History of equine embryo transfer LivestockHorsesDomestic horses as surrogates for endangered equids(?)3. Reproductive Anatomy and Physiology of the MareAnatomy of the marePhysiology of the estrous cycle Physiology of early embryonic development and early pregnancy4. Management of the donor mareSelection of the donorEvaluation of the donor (BSE)Management and Day of breeding (fresh, cooled, frozen semen)Palpation/ultrasound examinations relative to flush; daily vs every 6-8 hrs for frozen semen; BID if goal is to collect a small embryo at day 6.5 for cryopreservationInduction of ovulation (hCG and deslorelin)Donor mare management (PMIE, fluid, etc.)Estrous cycle control (Lights, P&E, PGF, hCG, Deslorelin, Regumate)Allow a mare to carry to term by approximately 10 years of ageAllowing mare to carry own every 3-4 yearsEffect of repeated flushing on uterine health and embryo recovery # flushes per year recommendedFertility of mares after flushing (i.e. same season)Problem mares (i.e. PMIE, etc.)Maiden mares (young vs older)Post partum mares (i.e. flushing on foal heat)5. SuperovulationHistoryTechniquesEFSHOptimal follicle size at onset Problems - same stallion vs. goal of different stallionsNot every mare responds to FSHPAF's and HAF's6. Embryo Collection Equipment (Box Table)Facilities (stocks vs stall, etc.)Procedure; (incl. clean out and wash up)Ultrasound prior to flush in problem