Title: Estrone Concentrations in the Peripheral Blood of Pregnant Cows. II. Values Around Parturition
Abstract: Estrone concentrations in whole peripheral blood of seven pregnant cows that calved normally were measured daily from at least three but not more than six days prepartum to four days postpartum.The highest average daily value was 8.2 +--1.2 ng per milliliter at five days prepartum.Blood estrone declined nearly continuously up to one day prepartum, but onset of this decline varied from one to five days before parturition.There was a relatively steep and significant decline between one day prepartum and one day postpartum.The lowest average blood estrone was four days postpartum, beyond which no samples were collected.A heifer that calved abnormally displayed an abnormally high blood estrone at the time of calving.