ISOTOPIC WATER DILUTION TECHNIQUE IN BODY-FLUID MEASUREMENT IN SOME DOMESTIC-ANIMAL SPECIES

Dilution procedures using tritiated water and Evans blue dye (T 1824) were applied to estimate total body water and plasma volume in small r uminants, pigs and cockrels during the two different seasons in Zimbab we. The amounts of total body water (TBW) obtained were between 60 % t o 85 % of the body weight in sheep and goats, 40 % to 60 % in pigs and 63 % to 75 % in cockrels. TBW values were significantly higher (P < 0 .05) in the small ruminants than in pigs and observed age differences were significant (P < 0.05) in the small ruminants. There were signifi cant (P < 0.05) seasonal differences in the total body water mean valu es but nonsignificant (P > 0.05) differences in the plasma volume mean values for the domestic species investigated.