Pharmacokinetics of antipyrine in calves during first 35 days of life.

The experiment was carried out on 10 bull-calves of black-white breed, aged 2-35 days. The following parameters of antipyrine pharmacokinetics were determined: Vd - volume of distribution, t0.5 - biological half-life, CA - metabolic clearance. It has been shown statistically that the volume of antipyrine distribution (expressed in 1/kg) was significantly decreasing with age of examined animals. The antipyrine half-life proved to be the longest on the 20th day of calves' life and the shortest on the 10th and 30th day. The maximum values of metabolic clearance of antipyrine were observed in calves aged 10 days and the minimum ones in animals aged 20 days. In the cases of t0.5 and CA a tendency to changes of values of these parameters of antipyrine pharmacokinetics in 10 days periods was observed.