Control of Reproduction in the Cow

Session 1: Follicular Growth and Ovulation.- Session 1a: Normal physiological processes.- Some observations on the development and function of ovarian follicles.- Oogenesis and follicular growth in the cow: implications for superovulation.- Session 1b: Nature of PMSG.- The biology of pregnant mare serum gonadotrophin (PMSG).- Relationship of PMSG to the pituitary gonadotrophins.- The production and standardisation of PMSG.- Discussion.- Session 1c: Superovulation studies.- Some studies on pregnant mare serum gonadotrophin (PMSG) and on endocrine responses after application for superovulation in cattle.- Ovarian responses in relation to endocrine status following PMSG stimulation in the cow.- Superovulation of cattle with PMSG and FSH.- Relationships between ovarian stimulation by PMSG and steroid secretion.- Factors affecting the variability of ovulation rates after PMSG stimulation.- Preliminary studies on the HCG binding properties of bovine granulosa cells.- Discussion.- Session 2: Ovum Recovery and Transfer.- Methods of ovum recovery and factors affecting fertilisation of superovu-lated bovine ova.- Recovery and transfer of embryos by non-surgical procedures in lactating dairy cattle.- The non-surgical recovery and transfer of bovine embryos.- Non-surgical recovery of bovine embryos under farm conditions.- Discussion.- Cervical embryo transfer at different stages in cattle.- Cattle twinning by non-surgical egg transfer.- Survival of cultured and transported bovine embryos following surgical and non-surgical transfers.- Practical application of non-surgical collection of bovine embryos in Danish pedigree cattle.- Discussion.- Session 3: Manipulation of Ova In Vitro.- Culture of mammalian ova.- Attempts to predict the viability of cattle embryos produced by superovulation.- In vitro exchange between the follicle and its culture medium.- In vitro storage of cattle embryos.- Deep freezing of bovine embryos - A field trial.- Embryo sexing with particular reference to cattle.- Manipulation of eggs in vitro — Attempt at long-term storage of oocytes at low temperatures without freezing.- Discussion.- Session 4: Oestrous Cycle Control and Fertility.- Management factors in oestrous cycle control.- Oestrous cycle control and fertility in beef cattle following short-term progestagen treatments.- Factors involved in oestrous cycle control in the bovine.- Modifying factors of fertility after different oestrous control treatments in beef cattle.- Improvement of the oestrous control in adult dairy cows.- Fertility control in cattle by determining progesterone in milk and milk-fat.- Use of progesterone concentrations in peripheral plasma or milk in cattle herd management.- Oestrous cycle control by means of prostaglandins and the progesterone levels in milk in dairy cattle.- Discussion.- Session 5: Discussion on Conference and Consideration of Future Research Requirements.- Discussion.- List of participants.