Abstract
The plasma and erythrocyte volumes of 18 rabbit fetuses delivered by caesarean section on day 30 of gestation were measured by a double labelling radioisotope technique after separation from the placenta. These late gestation fetuses were viable. A negative correlation was found between the bodyweight of the neonate and its blood volume expressed as a percentage of bodyweight. The equation of the linear regression line was Y = 92·3 - 3·9X. The haematocrit was 0·494 ± 0·029 I/l.