Pharmacokinetics of enrofloxacin after intravenous, intramuscular and oral administration in houbara bustard (Chlamydotis undulata macqueenii)

Abstract

The in-vitro activity of enrofloxacin against 117 strains of bacteria isolated from bustards was determined. Minimum inhibitory concentrations for 72% of the Proteus spp., E. coli, Salmonella spp. and Klebsiella spp. (n = 61) and for 48% of the Streptococci spp. and Staphylococci spp. (n = 31) were < or = 0.5 microg/mL. The minimum inhibitory concentration (MIC) of 76% of Pseudomonas spp. (n = 25) was < or = 2 microg/mL. Fourteen strains were resistant to concentrations > or = 128 microg/mL. The elimination half-lives (t1/2 elim beta) (mean +/- SEM) of 10 mg/kg enrofloxacin in eight houbara bustards (Chlamydotis undulata) were 6.80 +/- 0.79, 6.39 +/- 1.49 and 5.63 +/- 0.54 h after oral (p.o.), intramuscular (i.m.) and intravenous (i.v.) administration, respectively. Enrofloxacin was rapidly absorbed from the bustard gastro-intestinal tract and maximum plasma concentrations of 1.84 +/- 0.16 microg/mL were achieved after 0.66 +/- 0.05 h. Maximum plasma concentration after i.m. administration of 10 mg/kg was 2.75 +/- 0.11 microg/mL at 1.72 +/- 0.19 h. Maximum plasma concentration after i.m. administration of 15 mg/kg in two birds was 4.86 microg/mL. Bioavailability was 97.3 +/- 13.7% and 62.7 +/- 11.1% after i.m. and oral administration, respectively. Plasma concentrations of enrofloxacin > or = 0.5 microg/mL were maintained for at least 12 h for all routes at 10 mg/kg and for 24 h after i.m. administration at 15 mg/kg. Plasma enrofloxacin concentrations were monitored during the first 3 days of treatment in five houbara bustards and kori bustards (Ardeotis kori) with bacterial infections receiving a single daily i.m. injection of 10 mg/kg for 3 days. The mean plasma enrofloxacin concentrations in the clinical cases at 27 and 51 h (3.69 and 3.86 microg/mL) and at 48 h (0.70 microg/mL) were significantly higher compared with the 3 h and 24 h time intervals from clinically normal birds. The maximum plasma concentration (Cmax)/MIC ratio was ranked i.v. (10/mg/kg) > i.m. (15 mg/kg) > i.m. (10 mg/kg) > oral (10 mg/kg), but it was only higher than 8:1 for i.v. and i.m. administrations of enrofloxacin at 10 mg/kg and 15 mg/kg, respectively, against a low MIC (0.5 microg/mL). A dosage regimen of 10 mg/kg repeated every 12 h, or 15 mg/kg repeated every 24 h, would be expected to give blood concentrations above 0. 5 microg/mL and hence provide therapeutic response in the bustard against a wide range of bacterial infections.

Pharmacokinetics of Enrofloxacin in Emu (Dromaius novaehollandiae) Birds After Intravenous and Oral Bolus Administration

“…The t 1/2b of enrofloxacin recorded in this study was similar to values reported for greater rheas [17] and emus [18], but much slower than the results obtained in ostrich [19], whereas, Anadon et al [12] in chickens, Dimitrova et al [13] in turkey and Bailey et al [20] in houbara bustard observed longer elimination t 1/2b . The t 1/2b obtained in the present study indicates that emu tends to eliminate enrofloxacin slower than ostrich and faster than chickens and turkeys.…”

“…As compared to the total body clearance (Cl B ) [17]. The Cl B values for chickens (4.8 mL/ min kg); [12] and houbara bustard (5.7 mL/min kg); [20] are comparatively lesser than the result obtained in the present study. Cox et al [26] explained that the clearance and volume of distribution were proportional to body weight.…”

“…The AUC values reported in ostrich [19] and greater rheas [17] were lower while in broiler chicken [22] and houbara bustard [20] were higher as compared to the present study. The differences might be due to the difference in anatomy, dosages and species.…”

Pharmacokinetics of Enrofloxacin and Its Metabolite Ciprofloxacin in Male and Female Turkeys following Intravenous and Oral Administration

“…administration was similar to that found in chickens (Anado¨n et al, 1995;Bugyei et al, 1999;GarciaOvando et al, 1999;Knoll et al, 1999) and muscovy ducks (Intore et al, 1997). Its distribution and elimination are much slower than found in other bird species^hawks and owls (Herrenstein et al, 2000), psitacine birds (Flammer and Whitt-Smith, 2002) and houbara bustard (Bailey et al, 1997).…”

The disposition of marbofloxacin in Eurasian buzzards (Buteo buteo) after intravenous administration

“…This value suggests that marbofloxacin is widely distributed extravascularly as occurs with other fluoroquinolones. However, it is lower than the distribution volume of enrofloxacin (Bailey et al ., 1998; García Ovando et al ., 1999; Knoll et al ., 1999).…”