Fluid volumes in rainbow trout, Salmo gairdneri: application of compartmental analysis

Comp Biochem Physiol A Comp Physiol. 1987;87(3):703-9. doi: 10.1016/0300-9629(87)90386-0.


1. The measurement of fluid volumes by the indicator dilution technique and compartmental analysis was re-evaluated in free-swimming, undisturbed rainbow trout. 2. Plasma (33.5 ml/kg body wt) and blood (41.3 ml/kg body wt) volumes estimated by compartmental analysis from blood samples taken early (less than 5 min) after dye injection were 40% lower than volumes calculated by sampling late (greater than or equal to 80 min). 3. The rate of exchange of dye between plasma and interstitial fluid was high (48%/hr) compared to mammals (5%/hr) which supports the hypothesis that teleost capillaries have high protein permeability. 4. Total extracellular volume estimated using a single pool model (210.5 ml/kg body wt) of inulin kinetics was 20% higher than that calculated by a three pool model (172.8 ml/kg body wt).

MeSH terms

  • Animals
  • Evans Blue
  • Extracellular Space / metabolism*
  • Female
  • Inulin
  • Kinetics
  • Male
  • Models, Biological
  • Plasma Volume*
  • Salmonidae / physiology*
  • Trout / physiology*


  • Evans Blue
  • Inulin