OBSERVATIONS ON THE GROWTH RATES AND ORGAN WEIGHTS OF FETAL SHEEP AT ALTITUDE AND SEA LEVEL

¹ Instituto de Biologia Andina, Morococha, Peru and Harvard, Yale, Johns Hopkins, Florida and Boston Universities

Data are presented indicating that the fetuses carried by ewes at altitude (14,000 ft.) grow at the same rate as those borne by ewes at sea level. The number of placental cotyledons in both the altitude and sea level series is the same though their total weight tends to be higher in the latter. The heart/body weight ratio of the fetuses in the altitude and sea level series is the same, though it is higher in the ewes at altitude. These observations indicate that despite a reduced oxygen tension in the maternal uterine—and presumably placental—capillaries at altitude the fetal lamb can grow at the same rate as it does in a ewe at sea level.