Plasma and blood volume in the calf from birth till 90 days of age.

Determinations of plasma volume were made of 9 clinically healthy Swedish Red and White calves from birth to 90 days of age by means of the isotop dilution technique. Commercially available I labelled human serum albumin was used. Calculation of the total blood volume was based on the plasma volume and packed cell volume. The plasma and blood volumes increased per kg body weight in average 17 and 14% respectively from directly after birth to 24 hrs. old. From 1 to 90 days of age the plasma and blood volume fell steadily per kg body weight. Plasma volume expressed as a percentage of body weight was 5.3% at birth, 6.5% at 1 day old, and 4.9% at 90 days old. Corresponding values for blood volume were 8.4, 9.3 and 7.0%.