title: Pharmacokinetics of butorphanol delivered with an osmotic pump during a seven-day period in common peafowl (Pavo cristatus).
abstract: OBJECTIVE
  To determine pharmacokinetics of butorphanol delivered via osmotic pumps in common peafowl (Pavo cristatus) as a method for analgesic administration to avian species.
  
  
  METHODS
  14 healthy adult male common peafowl.
  
  
  METHODS
  A preliminary experiment was conducted with 2 birds to establish time point and concentration requirements. Then, the remaining 12 birds were anesthetized, and 2 osmotic pumps containing butorphanol (volume, 2 mL; mean dosage, 247 μg/kg/h) were implanted subcutaneously in each bird for 7 days prior to removal. Blood samples were collected before pump implantation (time 0); 3, 6, 12, 24, 48, 72, 96, 120, 144, and 168 hours after pump implantation; and 3 and 6 hours after pump removal. Plasma butorphanol concentrations were measured via liquid chromatography-mass spectrometry.
  
  
  RESULTS
  Plasma concentrations peaked (mean, 106.4 μg/L; range, 61.8 to 133.0 μg/L) at a mean of 39.0 hours, with no evidence of sedation in any bird. After pump removal, butorphanol was rapidly eliminated (half-life, 1.45 hours; range, 1.31 to 1.64 hours; n = 5). Mean clearance per fraction of dose absorbed was 2.89 L/kg/h (range, 2.00 to 5.55 L/kg/h). Mean amount of time the plasma butorphanol concentration was ≥ 60 μg/L was 85.6 hours (range, 3.5 to 155.3 hours).
  
  
  CONCLUSIONS
  Plasma concentrations of butorphanol in common peafowl were maintained at or above reported efficacious analgesic concentrations. This study established a method for administering analgesics to avian patients without the need for frequent handling or injections. Use of these osmotic pumps may provide options for avian analgesia.
authors.forename: Meredith M
authors.initials: MM
authors.lastname: Clancy
authors.forename: Butch
authors.initials: B
authors.lastname: KuKanich
authors.forename: John M
authors.initials: JM
authors.lastname: Sykes
mesh_terms: D000698:Analgesia; D000700:Analgesics / Q000008:administration & dosage / Q000097:blood; D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000097:blood; D000818:Animals; D001835:Body Weight; D002077:Butorphanol / Q000008:administration & dosage* / Q000097:blood; D002853:Chromatography, Liquid; D046094:Galliformes; D006207:Half-Life; D008297:Male; D013058:Mass Spectrometry; D009995:Osmosis; D010146:Pain; D013997:Time Factors
chemical_list: D000700:Analgesics; D000701:Analgesics, Opioid; D002077:Butorphanol