Pharmacokinetics of single doses of digoxin administered intravenously to ducks, roosters, and turkeys.
A single dose of digoxin was injected, IV, into 5 mature male turkeys (0.066 mg/kg of body weight), 8 male ducks (0.066 mg/kg), and 6 roosters (0.33 mg/kg). Twenty-three serial venous blood samples were collected before (baseline) and after the administration of digoxin to turkeys, ducks, and roosters. Plasma concentrations of digoxin were determined in duplicate by a radioimmunoassay that was validated for avian species. The plasma concentrations were best fitted by a 3 (turkeys, ducks)- and 2 (roosters)-compartment open model, with first-order elimination from the central compartment. Significant (P less than 0.05) kinetic differences were determined among species. Mean half-life (t1/2) for ducks, roosters, and turkeys were 8.30 +/- 2.70 (mean +/- SD), 6.67 +/- 3.50, and 23.7 +/- 4.8 hours, respectively. The volume of distribution at steady state (Vss) was 14.7 +/- 2.9, 3.13 +/- 0.49, and 2.27 +/- 0.36 L/kg, and total body clearance (CL) of drug was 1.54 +/- 0.43, 0.461 +/- 0.187, and 0.136 +/- 0.022 L/h/kg for ducks, roosters, and turkeys, respectively. The mean residence time was 10.3 +/- 3.9, 8.37 +/- 4.97, and 16.8 +/- 2.2 hours, respectively. Volume of distribution at steady state and CL in ducks were several fold higher than that in turkeys. The terminal half-life of digoxin determined for ducks and roosters in this study was considerably shorter than those previously reported for several mammalian species.
Pedersoli
W M
WM
Department of Physiology, College of Veterinary Medicine, Auburn University, AL 36849.
Ravis
W R
WR
Lee
H S
HS
Krista
L M
LM
Spano
J S
JS
D000818:Animals; D002645:Chickens / Q000097:blood / Q000378:metabolism*; D004077:Digoxin / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D004334:Drug Administration Schedule / Q000662:veterinary; D004372:Ducks / Q000097:blood / Q000378:metabolism*; D007275:Injections, Intravenous / Q000662:veterinary; D008297:Male; D011863:Radioimmunoassay / Q000662:veterinary; D013045:Species Specificity; D014422:Turkeys / Q000097:blood / Q000378:metabolism*
D004077:Digoxin