Growth of the pig: changes in red cell and plasma volumes

Abstract

In the pig, plasma volume increased from 58.0 ± 2.53 ml/kg on day 1 to 66.7 ± 3.35 (P < 0.05) on day 2, and decreased between days 7 and 9 to 56.4 ± 1.16 (P < 0.02). The next significant change in volume occurred at weaning: from 53.1 ± 1.24 ml/kg at wk 4 to 44.16 ± 2.2 at wk 5. It then increased to 56.1 ± 1.41 ml/kg by wk 7 and decreased to 48.5 ± 1.44 by wk 9; then between wk 10 and 11 it increased to 59.33 ± 3.01 (P < 0.005). Red cell volume on day 1 was 32.3 ± 1.25 ml/kg and decreased to 20.2 ± 1.37 (P < 0.01) on day 2. The only other change of significance in red cell volume over the 12 wk growth period was a small increase in volume to 24.5 ± 2.0 ml/kg from 20.2 ± 0.88 (P < 0.05) at wk 6. The mean for BVR(cells) was 0.88 ± 0.01 for the growth period. The pattern of changes in plasma and red cell volumes differed from those for the beagle.