Studies on the hypophysectomized ferret IX—The effect of hypophysectomy on pregnancy and lactation

Abstract

Hypophysectomy at the 21st day of pregnancy in the ferret may result in abortion or resorption of the foetuses. Hypophysectomy at the 35th day of pregnancy is followed by the delivery of dead or living young from 3-8 days later. Lactation is rarely initiated and never continued. The young invariably die. The injection of an extract of anterior hypophysis caused hypertrophy and secretion of milk in the mammary glands of 3 hypophysectomized animals, both before and after delivery of the young. Exposure but not removal of the pituitary at the 35th or 37th day of pregnancy caused no interference with the normal mechanism of parturition and lactation. Removal of the ovaries of 2 pregnant animals (35th day) resulted in premature parturition. Young born at 40 days post-coitum were reared, but not those born at 38 days post-coitum. Hypophysectomy of a ferret during lactation caused termination of milk secretion.