Applying Research in Herd Reproductive Service

Abstract

Major advances in our knowledge of bovine reproduction in the past 2 5 years have occurred in the fields of pathology, physiology, endocrinology, microbiology, nutrition and zootechnics. These have resulted in an increased understanding of puberty; the estrous cycle; ovulation; C.L. formation, maintenance and involution; pregnancy; parturition; uterine involution; sperm cell development; accessory gland function; copulation; ejaculation; sperm transport; fertilization and ova transplant. Radioimmunoassays and proteinbinding assays that can readily determine the blood levels of progesterone, estrogen, testosterone, corticosteroids, LH, and other proteinaceous or steroid hormones have rapidly forwarded research in endocrinology.