Table 1.

Comparison of the methods for the determination of GFR in birds

Method	GFR, ml/h
Slope intercept method assuming first order kinetics	21.08 (8.07)
Corrected two-pool determination	16.82 (6.15)
Allometrically predicted	11.01 (1.13)

Values are means (SD). GFR, glomerular filtration rate. Single pool determination utilizes the slope intercept method and Eq. 1. Two-pool determination utilizes the slope intercept method and Eq. 4, where the rapid phase of the decay curve is estimated. Allometrically predicted values us the equation GFR = 0.013 M_b^0.76 from Ref. 6.