[show abstract][hide abstract] ABSTRACT: The pharmacokinetic aspects of florfenicol (FLO) were investigated via intravenous (I.V.) and intramuscular (I.M.) injections in five goats at a dose of 20 mg kg(-1) b.wt. Animals were pre-treated with albendazole orally in a dose of 2.5 mg kg(-1) b.wt, ivermectin or rafoxanide subcutaneously in a dose 0.2 and 7.5 mg kg(-1) b.wt, respectively. Florfenicol was injected intramuscularly two hours following anthelmentic administration and blood samples were taken by jugular venapuncture at standardized intervals. The concentrations of florfenicol (FLO) in serum were determined by high performance liquid chromatography (HPLC) method. The obtained results revealed that ivermectin administration did not induce a significant difference in serum florfenicol concentration between anthelmentic-treated and non-treated goats. On the other hand, goats pre-treated with rafoxanide or albendazole showed a significant decrease in serum florfenicol level as compared to non-anthementic treated goats. The absorption half-life (t(½ab)), C(max), AUMC, AUC and systemic bioavailability (F%) are significantly decreased, whereas elimination half-life (t(½el)) and MRT are increased in goats pre-treated by the three tested anthementics.
Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 12/2010; 48(12):3340-4. · 2.99 Impact Factor
[show abstract][hide abstract] ABSTRACT: Following IV injection of doxycycline in a dose of 20 mg kg(-1) b.wt., its serum concentration was best fitted in two-compartment open model in chickens fed either on control or on anticoccidials-containing rations. Diclazuril and halofuginone resulted in a significant short distribution half-life (t(½α)) (7.17±0.39 and 11.88±1.05 min, respectively) and increased total body clearance (Cl(tot)) 0.37±0.024 and 0.295±0.034 L/kg/h, respectively. Following oral dosing the tested drug absorbed with t(½ab) of 41.38±1.6, 17.48±0.86 and 41.83±1.8 min, respectively and their C(max) values (3.18±0.18, 5.425±0.48 and 0.986±0.037 μg/ml) were attained at 2.07±0.097, 1.403±0.074 and 2.55±0.106 h. For doxycycline alone and in presence of diclazuril and halofuginone, respectively. Systemic bioavailability was 22.64±3.46, 86.74±9.23 and 22.38±3.09%, respectively. Following IM injection t(½ab) were 9.096±1.34 for doxycycline alone, 16.24±2.21 and 15.6±1.7 min in the presence of diclazuril and halofuginone, respectively. C(max) was 3.10±0.28, 4.63±0.57 and 0.55±0.07 μg/ml reached at 0.8±0.083, 1.13±0.126 and 1.21±0.105 h. For the antibiotic alone, and in presence of either diclazuril and halofuginone, respectively. Systemic bioavailability was 22.41±3.86, 88.97±12.9 and 12.31±0.99% in chickens fed on anticoccidial-free, diclazuril- and halofuginone-containing rations, respectively. Both the tested anticoccidials induced higher doxycycline tissue residues in all tested tissue samples.
Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 11/2010; 48(11):3209-14. · 2.99 Impact Factor
[show abstract][hide abstract] ABSTRACT: Disposition kinetics of danofloxacin and ciprofloxacin were studied in broiler chickens following intravenous, intramuscular and oral administration in a single dose of 5 and 10 mg/kg-1 body weight respectively. In addition, tissue distribution and residual pattern of both drugs were determined. The maximum serum concentration (Cmax) after intramuscular and oral administration were 1.03 and 0.55 mu/ml for danofloxacin and 2.92 and 1.24 mu/ml for ciprofloxacin attained at 0.8 and 2.43 and 0.55 and 1.27 hours for danofloxacin and ciprofloxacin respectively. The volume of distribution and systemic bioavailability were higher for danofloxacin (Vdss 2.21 L/kg and F% 96.56 and 81.4%) as compared with ciprofloxacin (Vdss 1.41 L/kg and F% 75.5 and 29.4%). Data relating to intravenous injection for both drugs were analyzed using a two compartment open model curve fit. Danofloxacin and ciprofloxacin were not detected in the serum of broilers at the 5th and 3rd day respectively following the drugs withdrawal while were detected in liver, kidneys, spleen and lungs. Danofloxacin completely disappeared from all tissues at the 13th day after stopping of the drug medication but ciprofloxacin disappeared after 5 days only.
DTW. Deutsche tierärztliche Wochenschrift 11/2001; 108(10):429-34. · 0.41 Impact Factor
[show abstract][hide abstract] ABSTRACT: The pharmacokinetics of danofloxacin was determined in five clinically normal adult female goats after intravenous (IV) or intramuscular (IM) doses of 1.25 mg/kg body weight. Blood and urine samples were collected from each animal at precise time intervals. Serum and urine concentrations were determined using microbiological assay methods and the data were subjected to kinetic analysis. After intravenous injection, the serum concentration time curves of danofloxacin were characteristic of a two-compartment open model. The drug was rapidly distributed and eliminated with half-lives of 17.71 +/- 1.38 min and 81.18 +/- 3.70 min, respectively. The drug persisted in the central, highly perfused organs with a K12/K21 ratio of 0.67 +/- 0.25. The mean volume of distribution at a steady state (Vdss was 1.42 +/- 0.15 L/kg. After intramuscular administration, the serum concentration peaked after 0.58 +/- 0.04 h at approximately 0.33 +/- 0.01 microg/ml. While danofloxacin could be detected in serum for 4 and 6 h, it was recovered in urine for up to 24 and 72 h after IV and IM administration, respectively. The systemic bioavailability after IM injection was 65.70% +/- 10.28% and the serum protein-bound fraction was 13.55 +/- 1.78%.
Veterinary Research Communications 08/2001; 25(5):367-77. · 1.08 Impact Factor
[show abstract][hide abstract] ABSTRACT: Florfenicol, a monofluorinated analogue of thiamphenicol, has antibacterial activity against a broad spectrum of bacterial strains, including enteric bacteria that are resistant to chloramphenicol and thiamphenicol. The pharmacokinetics of florfenicol was studied following a single intravenous bolus or intramuscular injections at a dose of 20 mg/kg body weight, in five healthy goats. Serum florfenicol concentrations were determined using two analytical methods: microbiological assay and high-performance liquid chromatography (HPLC). Pharmacokinetic analysis was performed using redundant routine equations and the results derived from each method were compared. While florfenicol was detected for up to 4 and 8 h after administration by the bioassay, the drug was recovered in serum after 12 and 24 h by HPLC following intravenous and intramuscular injections, respectively. Comparison of the concentration profiles obtained by the two methods revealed substantial differences in the resultant kinetic data. Values for the initial serum concentration, elimination half-life, the area under the serum concentration-time curve, the mean residence time, and the systemic bioavailability were significantly (P < 0.01) higher when florfenicol concentrations were determined using HPLC. In conclusion, differences between analytical methodologies should be considered when interpreting the kinetic data for clinical use. However, both the hepatic biotransformations and the interchangeability of enantiomers need further investigation.
Journal of Veterinary Medicine Series A 04/2001; 48(3):129-36. · 0.93 Impact Factor
[show abstract][hide abstract] ABSTRACT: The single-dose disposition kinetics of florfenicol was determined in healthy, non-lactating Egyptian goats, after its intravenous (i.v.) and intramuscular (i.m.) administration at 20 mg kg-1 b.wt. Drug concentrations in serum and urine were determined using microbiological assay method and data was subjected to a kinetic analysis. Florfenicol concentrations in serum decreased in a bi-exponential manner after intravenous administration with distribution (t1/2 alpha) and elimination (t1/2 beta) half-lives of 10.256 +/- 0.938 and 56.237 +/- 3.102 minute, respectively. The steady-state volume of distribution (Vdss) and total body clearance (Cltot) were 3.413 +/- 0.304 l kg-1 and 3.306 +/- 0.333 l kg h-1. After intramuscular administration, the peak serum concentration (Cmax) was 0.859 +/- 0.025 micrograms ml-1, achieved at (Tmax) 1.220 + 0.045 h. Florfenicol was detected in urine up to 24 and 96 hour after i.v. and i.m. administration, respectively. The extent of the protein binding and systemic bioavailability of florfenicol were 22.45 +/- 1.727% and 65.718 +/- 3.372%, respectively.
DTW. Deutsche tierärztliche Wochenschrift 05/2000; 107(4):147-50. · 0.41 Impact Factor
[show abstract][hide abstract] ABSTRACT: Evaluation of the pharmacokinetic properties of 4 antibiotics: penicillin-G (P), streptomycin (S), chloramphenicol (C) and oxytetracycline (O) was performed in groups of camels following a single i.m. injection of therapeutic doses, i.e. 6000 IU, 10, 4 and 3 mg/kg b.wt., respectively. The concentrations of these antibiotics in serum were determined by microbiological assay methods. The highest serum concentrations were reached after 0.42, 1.44, 4.02 and 0.94 hr for P, S, C, and O respectively with corresponding t 1/2 alpha values of 0.12, 0.28, 1.48 and 0.17 hr and t 1/2 beta values of 1.09, 8.28, 6.20 and 7.00 hr.
Archives internationales de pharmacodynamie et de thérapie. 03/1983; 261(2):186-95.
[show abstract][hide abstract] ABSTRACT: In 12 experiments on 6 mongrel dogs, furosemide was given both orally and i.v. in a dose of 20mg/kg. Following i.v. injection, the blood concentration curve followed an open one-compartment model. The elimination half-lives after both oral and i.v. routes were nearly similar, i.e. 1.42 +10.13 and 1.13 +0.06 hours respectively. The apparent volume of distribution corresponded well to the total body water (about 60%), i.e. 69.64 +5.61 and 52.06+4.82% b.wt. after oral and i.v. routes respectively. The body clearance of this drug after i.v. and oral administration showed close values, i.e. 5.27 +0.19 and 5.96 +0.14 mg/kg(-1) min(-1) respectively. The systemic bioavailablity of furosemide after oral administration amounted to 77.13 +5.24% with a maximum blood conc. (Cmax.) of 22.73 +2.03 microgram/ml, 30 min after administration.
Archives internationales de pharmacodynamie et de thérapie. 10/1981; 253(1):4-10.
[show abstract][hide abstract] ABSTRACT: Eight experiments were carried out on eight clinically healthy non-pregnant ewes. Each animal was injected intravenously with either sulphadiazine or sulphadimidine at a dose rate of 100 mg/kg body weight. A two-compartment pharmacokinetic model was developed to describe the disposition of these drugs. The elimination half-lives were 7.15 +/- 0.58 h and 9.51 +/- 0.59 h and the distribution half-lives were 0.56 +/- 0.07 h and 0.42 +/- 0.05 h for sulphadiazine and sulphadimidine, respectively. The apparent specific volumes of distribution were less than 1 litre/kg (0.410 and 0.501 litres/kg for sulphadiazine and sulphadimidine, respectively) which indicates a relatively lower distribution of these drugs to tissues than in plasma in sheep. The degree of plasma protein binding was similar for both drugs (19.15 +/- 0.55% and 23.12 +/- 0.32%) for sulphadiazine and sulphadimidine, respectively). Serum concentrations of ketone bodies, total lipids and calcium were significantly reduced, and blood glucose concentration significantly increased following administration of both of these sulphonamides, whilst serum total protein concentration was unaltered. The serum cholesterol concentration was significantly reduced following sulphadiazine administration, but not after sulphadimidine.
Journal of Veterinary Pharmacology and Therapeutics 10/1981; 4(3):173-82. · 1.35 Impact Factor
[show abstract][hide abstract] ABSTRACT: 1. Three groups of four clinically healthy buffaloes were injected with sulphadiazine, or sulphadimidine, or sulphathiazole in a single dose of 100 mg/kg body weight. 2. Changes in the serum enzyme activities (SGOT, SGPT and alkaline phosphatase) observed with the tested sulphonamides were insignificant, except for increases in SGOT level 6 h after sulphathiazole injection, and in GOT/GPT ratio 30 min and 24 h after sulphadimidine injection. 3. The creatinine level was not affected in sulphonamide-injected animals. All blood samples collected 15 min to 24 h after sulphathiazole injection showed marked increase in glucose and urea levels. Concerning the other two sulphonamides, no significant change was observed in these parameters except for an increased glucose level 24 h after sulphadiazine injection.
Clinical and Experimental Pharmacology and Physiology 9(2):179-83. · 2.16 Impact Factor