Swine Hematology from Birth to Maturity. III. Blood Volume of the Nursing Pig

Abstract

The changes in relative blood, plasma and cell volumes, as well as the changes in plasma protein concentration, the concentration of the various plasma protein fractions and hematocrit from birth to 5 weeks of age, were studied in 169 pigs. It was found that the absorption of protein from the gut during the first 12 to 24 hours of life produced an increase in plasma protein concentration which in turn was associated with an increase in relative blood volume. The changes in relative blood volume were apparently a reflection of changes in relative plasma volume since the relative cell volume remained constant. The relative blood volume decreased as weight rapidly increased. The initial increase in plasma protein was due to an increase in γ- and β-globulins absorbed from colostrum although their concentration decreased after 24 hours of age. Albumin concentration, after an initial decrease, increased rapidly after 12 hours of age to comprise 60% of the plasma protein at 5 weeks of age. The relatively high amounts of a-globulins at birth decreased during the first 6 hours of life and remained constant for the rest of the study.