[The effect of temperature on the motor activity of the chick embryo and amnion at 5-14 days of development]

Abstract

It has been shown that cooling the developing eggs from 37.7 degrees C results cessation of motor activity of the amnion in 5-14-day embryos at 36-33 degrees C, whereas motor activity of the embryo remains unaffected up to 31-26 degrees C. Immobilization of the embryo was observed on cooling up to 22-18 degrees C. The recovery of motor activity after cooling during heating takes place in a reverse order. Embryonic movements are observed at 18-23 degrees C, contractions of the amnion--at 28-33 degrees C. These experiments reveal complete independence of embryonic movements from the amnion. Motor activity of the amnion is related to that of the embryo only between the 8th and the 10th day of incubation.