Flunixin pharmacokinetics and serum thromboxane inhibition in the dog

Flunixin meglumine administered orally to beagle dogs at doses of 0.55, 1.10 or 1.65 mg/kg bodyweight was rapidly absorbed to produce maximum mean plasma concentrations of 2.40 +/- 0.70, 4.57 +/- 1.12 and 7.42 +/- 2.07 micrograms/ml, respectively. Thereafter, the plasma concentrations of flunixin fell rapidly to values less than 0.10 micrograms/ml from 24 hours after drug administration at all dosage levels. The maximum mean inhibition of serum thromboxane B2 was 91.5 per cent after the lowest dose of flunixin and 98.8 per cent for both the intermediate and high dose rates. At plasma concentrations of flunixin above 2 micrograms/ml there was more than 90 per cent inhibition of thromboxane.     

Pharmacokinetics and clinical efficacy of a cinchophen and prednisolone combination in the dog

The kinetics and efficacy of a cinchophen prednisolone combination preparation (PLT) were assessed in the dog. Cinchophen administered at a dose rate of 12-5 mg/kg intravenously had a volume of distribution (Vd area) of 0–13 litres/kg, a clearance rate (Cl) of 0–15 litres/h and a half-life (t _1/2β of 7–92 hours. Following oral administration the bioavailability was 87-21 per cent. Prednisolone administered at a dose rate of 0–15 mg/kg intravenously had a Vd area of 2–7 litres/kg, a CI of 0–116 litres/h and a t_1/2β of 1–11 hours. PLT given to dogs with osteoarthritis at a dosage range of between 25 and 44 mg/kg per day cinchophen and between 0–125 and 0–220 mg/kg per day prednisolone for a maximum of 14 days significantly improved lameness (P<0–001), weight bearing (P<0–005), joint mobility (P<0–01) and stiffness (P<0–001) scores and was similar in clinical efficacy to phenylbutazone.     

Pharmacokinetics of aditoprim in dogs after intravenous and oral administration: a preliminary study

The pharmacokinetics of aditoprim (2,4-diam-ino-5-[4-[dimethylamino]-3,5-dimethoxybenzyl] pyrimidine), a dihydrofolate reductase inhibitor, were studied in three eight to 17-month-old beagle dogs. The drug was alternately injected intravenously and administered orally as a tablet in two separate experiments. The doses ranged from 4–27 to 7–25 mg/kg bodyweight. The mean plasma clearance (CI) was 15-3 ml/min/kg and the mean volume of distribution (V_ss) 13-1 litres/kg. The mean plasma elimination half-life times after intravenous injection and oral administration were 11-6 and 9-6 hours, respectively. Aditoprim was readily (t_max= one to four hours) and completely absorbed from the intestinal tract (f = 89 per cent).     

Pharmacokinetics, tolerance and serum thromboxane inhibition of carprofen in the dog

The non-steroidal anti-inflammatory drug (NSAID) carprofen was administered to dogs as a mixed-micelle solution at a dose rate of 0–7 mg/kg intravenously, as a palatable paste at a dose rate of 0–7 mg/kg orally, and as an oral tablet formulation at a dose rate of 0–7 mg/kg and 4-0 mg/kg orally for pharmacokinetic studies. It was also administered as an oral tablet formulation at a dose rate of 9-0 mg/kg orally daily for 14 days in a tolerance study. The pharmacokinetics following intravenous administration at a dose rate of 0–7 mg/kg indicate that carprofen has a small volume of distribution (Vd area = 0–09-0-25 litres), a slow systemic clearance (Cls = 1–34-5-57 ml/min) and an elimination half-life of 3–20-11-77 hours. Both oral paste and tablet preparations were highly bioavailable and absorption was proportional to dose rate at 0–7 mg/kg and 4-0 mg/kg bodyweight. Given once daily at dose rates likely to be used clinically it is unlikely to accumulate in the plasma. Carprofen administered as a palatable paste at a dose rate of 0–7 mg/kg did not inhibit serum thromboxane generation and this drug may therefore have a mode of action different from most NSAIDs. Carprofen was well tolerated when administered as an oral tablet formulation at a dose rate of 9.0 mg/kg daily for 14 days in healthy beagle dogs.     

Effect of hypocalcaemia on blood flow distribution in sheep

Cardiac output, the proportion of blood passing through arteriovenous shunts and blood flow distribution to various organs were measured and compared in five normocalcaemic and five hypocalcaemic sheep using radioactive microspheres. Hypocalcaemia was induced by infusing sodium EDTA solution intravenously for two hours. There was evidence that microspheres were leached from liver, muscle, adrenal and thyroid tissues during the induction of hypocalcaemia. Hypocalcaemia reduced blood flow rates by more than 58 per cent in all tissues examined except kidney (48 per cent), heart (53 per cent), lung (10 per cent) and bladder (47 per cent) and reduced cardiac output from 3.70 +/- 0.19 (mean +/- SE) litres min-1 to 2.39 +/- 0.14 litres min-1. Approximately 2.2 per cent of cardiac output passed through arteriovenous shunts. This percentage was unaffected by hypocalcaemia.     

Pharmacokinetics of cefotaxime in the dog

Each of five dogs was given cefotaxime at a dose rate of 50 mg/kg by intravenous, intramuscular and subcutaneous routes, in three separate treatments. Plasma concentration time profiles were characterised by a linear two-compartment model after the intravenous administration. After intravenous, intramuscular and subcutaneous injections the mean biological half-lives were 0.74, 0.83 and 1.71 hours, respectively. The apparent steady state volume of distribution was 0.48 litre/kg and body clearance after intravenous injection was approximately 0.63 litre/hour/kg. After intramuscular and subcutaneous injections peak plasma cefotaxime concentrations were 47 +/- 15 and 29.6 +/- 16 micrograms/ml at 0.5 and 0.8 hours, respectively. The average bioavailability of cefotaxime given by intramuscular injection was 86.5 per cent and for cefotaxime given subcutaneously it was approximately 100 per cent. After two hours, the cefotaxime plasma concentration remained higher after subcutaneous than after intramuscular administration.     

Pharmacokinetics and interactions of digoxin with phenobarbital in dogs

In one experiment, 5 dogs were administered digoxin (0.022 mg/kg of body weight, IV), were rested for 2 weeks, were then given phenobarbital (13.2 mg/kg orally) for 14 days, and then were given digoxin again (0.022 mg/kg, IV). Comparing prephenobarbital (control) digoxin half-lives of 42.4 +/- 8.8 hours and postphenobarbital digoxin half-lives of 18.0 +/- 2.2 hours, the half-life was significantly (P less than 0.05) decreased after phenobarbital administration. Clearance was increased by 84%, and the volume of distribution given was decreased by 34%. In a second experiment, 5 dogs were given digoxin (0.022 mg/kg, orally) daily for 11 days, and the digoxin kinetics were evaluated after the last dosing. The dogs were then rested and given phenobarbital (13.2 mg/kg, orally) once daily for 14 days and digoxin (0.022 mg/kg) once daily for 11 days, and the pharmacokinetics of digoxin was determined on the last day of dosing. Significant differences in steady-state serum concentrations and the pharmacokinetics of digoxin were not found between the control and phenobarbital phases of the experiment. Mean (+/- SD) half-lives of digoxin were 29.0 +/- 7.2 hours before phenobarbital treatment (control) and were 34.8 +/- 7.2 hours after phenobarbital treatment. In comparing results of the single-dose experiment vs the oral multiple-dose experiment, dogs had shorter half-lives for digoxin after multiple dosing. Therefore, if phenobarbital and digoxin are to be chronically coadministered orally, an adjustment in the digoxin dose is not necessary.     

The anti-emetic efficacy of maropitant (Cerenia) in the treatment of ongoing emesis caused by a wide range of underlying clinical aetiologies in canine patients in Europe

OBJECTIVES: The efficacy of maropitant (Cerenia; Pfizer Inc.) as an anti-emetic for use in dogs with ongoing emesis was evaluated in a two-phase multi-centric study conducted at veterinary clinics in France, Italy, Slovakia and the UK. METHODS: In phase I, dogs with ongoing emesis were randomised in a 1:1 ratio to either maropitant (32 dogs) or metoclopramide (34 dogs). In phase II, dogs were randomised in a 2:1 ratio to maropitant (77 dogs) or metoclopramide (40 dogs). Maropitant was administered subcutaneously at 1 mg/kg/day for up to five days. Metoclopramide was administered as recommended on the product labels as licensed at 0.5 to 1 mg/kg/day subcutaneously or orally with the daily dose divided over two to three administrations per day for up to three to five days. RESULTS: In phase I, 97 per cent of dogs treated with maropitant and 71 per cent of dogs treated with metoclopramide did not vomit after treatment (P<0.01). The mean number of emetic events after maropitant treatment was significantly reduced compared with that after metoclopramide treatment (P=0.01). In phase II, the occurrence of emesis was lower for maropitant during the first 24 hours (P<0.0001) and for each day thereafter. CLINICAL SIGNIFICANCE: A single daily dose of maropitant was more effective than metoclopramide administered two or three times daily in the treatment of emesis caused by various aetiologies in dogs.     

Pharmacokinetics and bioavailability of spiramycin in pigs.

The pharmacokinetics of spiramycin in pigs were investigated after intravenous and oral administration. The potential therapeutically effective blood level was established after a single administration and examined in a subsidiary five day study. The rapid intravenous injection of 25 mg spiramycin/kg bodyweight produced marked salivation in all the test animals. The elimination half-life (2.3 +/- 1.2 hours) was relatively short, in accordance with the total body clearance rate (27.3 +/- 10.1 ml/minute/kg). The high volume of distribution (5.2 +/- 2.2 litres/kg) was due to the accumulation of the drug in the body tissues. The maximum plasma concentration (4.1 +/- 1.7 micrograms/ml) after oral administration of 85 to 100 mg spiramycin/kg bodyweight was reached after 3.7 +/- 0.8 hours and the half-life of the elimination phase was 6.0 +/- 2.4 hours. The oral bioavailability was 45.4 +/- 23.4 per cent. Ad libitum feeding of a diet containing 2550 mg spiramycin/kg produced a steady state concentration of 0.96 +/- 0.27 micrograms/ml. This plasma concentration would provide a potentially therapeutically effective blood concentration against Mycoplasma species, Streptococcus species and Staphylococcus species.     

Long-term efficacy and safety of firocoxib in the treatment of dogs with osteoarthritis

Thirty-nine client-owned dogs with osteoarthritis were treated with 5 mg/kg firocoxib administered orally, once a day for 52 weeks. Veterinary examinations were performed on approximately days 0, 15, 90, 180, 270 and 360. Twenty-five dogs completed the study. The withdrawal rate associated with gastrointestinal side effects was low (5.1 per cent of dogs). Based on the owners' assessment, 82 per cent of the dogs had improved at day 15, 84 per cent of the 32 remaining dogs had improved at day 90, and 96 per cent of the 25 dogs that completed the trial had improved at day 360. During this trial, 12 (48 per cent) of the 25 remaining dogs showed an improvement in their lameness from day 90 to day 360 (P<0.05).     

Pharmacokinetics of norfloxacin in dogs after single intravenous and single and multiple oral administrations of the drug

Norfloxacin was given to 6 healthy dogs at a dosage of 5 mg/kg of body weight IV and orally in a complete crossover study, and orally at dosages of 5, 10, and 20 mg/kg to 6 healthy dogs in a 3-way crossover study. For 24 hours, serum concentration was monitored serially after each administration. Another 6 dogs were given 5 mg of norfloxacin/kg orally every 12 hours for 14 days, and serum concentration was determined serially for 12 hours after the first and last administration of the drug. Complete blood count and serum biochemical analysis were performed before and after 14 days of oral norfloxacin administration, and clinical signs of drug toxicosis were monitored twice daily during norfloxacin administration. Urine concentration of norfloxacin was determined periodically during serum acquisition periods. Norfloxacin concentration was determined, using high-performance liquid chromatography with a limit of detection of 25 ng of norfloxacin/ml of serum or urine. Serum norfloxacin pharmacokinetic values after single IV dosing in dogs were best modeled, using a 2-compartment open model, with distribution and elimination half-lives of 0.467 and 3.56 hours (harmonic means), respectively. Area-derived volume of distribution (Vd area) was 1.77 +/- 0.69 L/kg (arithmetic mean +/- SD), and serum clearance (Cls) was 0.332 +/- 0.115 L/h/kg. Mean residence time was 4.32 +/- 0.98 hour. Comparison of the area under the curve (AUC; derived, using model-independent calculations) after iv administration (5 mg/kg) with AUC after oral administration (5 mg/kg) in the same dogs indicated bioavailability of 35.0 +/- 46.1%, with a mean residence time after oral administration of 5.71 +/-2.24 hours. Urine concentration was 33.8 +/- 15.3 micrograms/ml at 4 hours after a single dose of 5 mg/kg given orally, whereas concentration after 20 mg/kg was given orally was 56.8 +/- 18.0 micrograms/ml at 6 hours after dosing. Twelve hours after drug administration, urine concentration was 47.4 +/- 20.6 micrograms/ml after the 5-mg/kg dose and 80.6 +/- 37.7 micrograms/ml after the 20/mg/kg dose.(ABSTRACT TRUNCATED AT 250 WORDS)     

Plasma cortisol response to ketoconazole administration in dogs with hyperadrenocorticism

The effect of orally administered ketoconazole on plasma cortisol concentration in dogs with hyperadrenocorticism was evaluated. Every 30 minutes from 0800 hours through 1600 hours and again at 1800 hours, 2000 hours, and 0800 hours the following morning, 15 clinically normal dogs and 49 dogs with hyperadrenocorticism had plasma samples obtained and analyzed for cortisol concentration. The mean (+/- SD) plasma cortisol concentration for the initial 8-hour testing period was highest in 18 dogs with adrenocortical tumor (5.3 +/- 1.6 micrograms/dl), lowest in 15 control dogs (1.3 +/- 0.5 micrograms/dl), and intermediate in 31 dogs with pituitary-dependent hyperadrenocorticism (PDH; 3.4 +/- 1.2 micrograms/dl). Results in each of the 2 groups of dogs with hyperadrenocorticism were significantly (P less than 0.05) different from results in control dogs, but not from each other. The same cortisol secretory experiment was performed, using 8 dogs with hyperadrenocorticism (5 with PDH; 3 with adrenocortical tumor) before and after administration at 0800 hours of 15 mg of ketoconazole/kg of body weight. Significant (P less than 0.05) decrease in the 8-hour mean plasma cortisol concentration (0.9 +/- 0.2 microgram/dl) was observed, with return to baseline plasma cortisol concentration 24 hours later. Twenty dogs with hyperadrenocorticism (11 with PDH, 9 with adrenocortical tumor) were treated with ketoconazole at a dosage of 15 mg/kg given every 12 hours for a half month to 12 months. The disease in 2 dogs with PDH failed to respond to treatment, but 18 dogs had complete resolution of clinical signs of hyperadrenocorticism and significant (P less than 0.05) reduction in plasma cortisol responsiveness to exogenous adrenocorticotropin (ACTH).(ABSTRACT TRUNCATED AT 250 WORDS)     

Pharmacokinetics of single doses of phenobarbital given intravenously and orally to dogs

Pharmacokinetics of phenobarbital was studied in 10 healthy dogs after single IV or oral administration. Phenobarbital sodium was administered IV to 5 dogs in group A (5.5 mg/kg of body weight) and 5 dogs in group B (15 mg/kg). Serial venous blood samples (n = 21) were collected from each dog before (base line) and after the administration of phenobarbital sodium for pharmacokinetic evaluation. After a 30-day resting period, 3 dogs in group A and 3 in group B were randomly selected and used for an IV crossover treatment. The IV treatment mean half-life of phenobarbital sodium was 92.6 +/- 23.7 and 72.3 +/- 15.5 hours, whereas mean total clearance was 5.60 +/- 2.31 and 6.66 +/- 0.78 ml/hr/kg for doses of 5 and 15 mg/kg, respectively. The mean residence time was 124 +/- 34 hours and 106 +/- 23 hours for the 5.5 and 15 mg/kg, IV doses, respectively. Significant differences (P greater than 0.05) were not observed in pharmacokinetic parameters between the 2-dose study. After a 35-day resting period, dogs in groups A and B were treated as described for the single IV treatment, except that they were given a phenobarbital tablet orally. Serial venous blood samples (n = 24) were collected before (base line) and after the administration of phenobarbital. Mean bioavailability was 88.1 +/- 12.4% and 96.8 +/- 9.0%, half life of absorption was 0.263 +/- 0.185 and 0.353 +/- 0.443 hour, and lag time was 0.611 +/- 0.683 and 0.741 +/- 0.554 hour for groups A and B, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Evaluation of the concentration of marbofloxacin in alveolar macrophages and pulmonary epithelial lining fluid after administration in dogs

OBJECTIVE: To determine concentrations of marbofloxacin in alveolar macrophages (AMs) and epithelial lining fluid (ELF) and compare those concentrations with plasma concentrations in healthy dogs. ANIMALS: 12 adult mixed-breed and purebred hounds. PROCEDURE: 10 dogs received orally administered marbofloxacin at a dosage of 2.75 mg/kg every 24 hours for 5 days. Two dogs served as nontreated controls. Fiberoptic bronchoscopy and bronchoalveolar lavage procedures were performed while dogs were anesthetized with propofol, approximately 6 hours after the fifth dose. The concentrations of marbofloxacin in plasma and bronchoalveolar fluid (cell and supernatant fractions) were determined by use of high-performance liquid chromatography with detection of fluorescence. RESULTS: Mean +/- SD plasma marbofloxacin concentrations 2 and 6 hours after the fifth dose were 2.36 +/- 0.52 microg/mL and 1.81 +/- 0.21 microg/mL, respectively. Mean +/- SD marbofloxacin concentration 6 hours after the fifth dose in AMs (37.43 +/- 24.61 microg/mL) was significantly greater than that in plasma (1.81 +/- 0.21 microg/mL) and ELF (0.82 +/- 0.34 microg/mL), resulting in a mean AM concentration-to-plasma concentration ratio of 20.4, a mean AM:ELF ratio of 60.8, and a mean ELF-to-plasma ratio of 0.46. Marbofloxacin was not detected in any samples from control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Marbofloxacin concentrations in AMs were greater than the mean inhibitory concentrations of major bacterial pathogens in dogs. Results indicated that marbofloxacin accumulates in AMs at concentrations exceeding those reached in plasma and ELF The accumulation of marbofloxacin in AMs may facilitate treatment for susceptible intracellular pathogens or infections associated with pulmonary macrophage infiltration.     

Reduced dosage of ketoprofen for the short-term and long-term treatment of joint pain in dogs

Two studies were conducted under laboratory conditions with 16 dogs to investigate the analgesic effectiveness of a low dose of ketoprofen in a short-term sodium urate crystal-induced synovitis model of arthritis. The effect of the treatment, defined as the improvement in peak vertical force weight bearing was evaluated in the first study at three dose levels. A single oral dose of 0.25 mg/kg ketoprofen was significantly better (P < 0.01) than the control (0 mg), but doses of 0.5 and 0.75 mg/kg did not improve the dogs' weight bearing further. The second study investigated the efficacy and safety of the 0.25 mg/kg dose administered daily for 30 days. The beneficial effects of ketoprofen at this dose were constant, with the treated dogs bearing 89.1 per cent of the baseline vertical force four hours after the induction of arthritis on day 1 and 92.2 per cent on day 29, compared with 42 per cent and 34 per cent of the baseline in the untreated dogs. No gastrointestinal or other side effects were observed during the treatment.     

Effects of urine alkalization and activated charcoal on the pharmacokinetics of orally administered carprofen in dogs

OBJECTIVE: To investigate the effects of oral administration of activated charcoal (AC) and urine alkalinization via oral administration of sodium bicarbonate on the pharmacokinetics of orally administered carprofen in dogs. ANIMALS: 6 neutered male Beagles. PROCEDURES: Each dog underwent 3 experiments (6-week interval between experiments). The dogs received a single dose of carprofen (16 mg/kg) orally at the beginning of each experiment; after 30 minutes, sodium bicarbonate (40 mg/kg, PO), AC solution (2.5 g/kg, PO), or no other treatments were administered. Plasma concentrations of unchanged carprofen were determined via high-performance liquid chromatography at intervals until 48 hours after carprofen administration. Data were analyzed by use of a Student paired t test or Wilcoxon matched-pairs rank test. RESULTS: Compared with the control treatment, administration of AC decreased plasma carprofen concentrations (mean +/- SD maximum concentration was 85.9 +/- 11.9 mg/L and 58.1 +/- 17.6 mg/L, and area under the time-concentration curve was 960 +/- 233 mg/L x h and 373 +/- 133 mg/L x h after control and AC treatment, respectively). The elimination half-life remained constant. Administration of sodium bicarbonate had no effect on plasma drug concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: After oral administration of carprofen in dogs, administration of AC effectively decreased maximum plasma carprofen concentration, compared with the control treatment, probably by decreasing carprofen absorption. Results suggest that AC can be used to reduce systemic carprofen absorption in dogs receiving an overdose of carprofen. Oral administration of 1 dose of sodium bicarbonate had no apparent impact on carprofen kinetics in dogs.     

Comparison of yearling, two-year-old and adult Thoroughbreds using a standardised exercise test

The purpose of this study was to compare exercise measurements in yearling, two-year-old and adult Thoroughbreds using a standardised treadmill incremental exercise test. Peak oxygen consumption (VO2 peak: 128.0 +/- 2.1, 140.0 +/- 2.1, 163.7 +/- 3.4; ml/kg/min +/- se, P less than 0.05), peak packed cell volume (PCV peak: 0.50 +/- 0.01, 0.58 +/- 0.01, 0.64 +/- 0.01 litres/litre +/- se, P less than 0.05) and the maximum number of steps completed in the exercise test (STEPmax: 7.7 +/- 0.1, 8.1 +/- 0.1, 8.6 +/- 0.1; steps +/- se, P less than 0.05) increased with age and degree of physical activity. Peak venous lactate concentration (LACpeak: 21.3 +/- 1.5, 19.5 +/- 1.7, 14.4 +/- 1.7; mmol/litre +/- se, P less than 0.05) and peak respiratory exchange ratio (Rpeak) were significantly higher in both groups of younger horses compared to the adult racehorses. Peak heart rate (HRpeak: 230 +/- 2, 231 +/- 3, 229 +/- 3; beats/min +/- se) did not change with age or training. The rate of change of VO2 between steps in the exercise test (VO2trans) was significantly lower in the adult racehorses at the highest exercise intensities. The slopes of the linear approximation between R (LinR bx), the natural log transformation of venous lactate concentration (LogLAC bx), and heart rate (HR bx) with velocity were significantly lower in the trained adult racehorses. The slope of venous lactate concentration normalised to per cent VO2peak (LogLAC per cent bx) was significantly lower and R breakpoint (R brkpt) normalised to per cent VO2peak was significantly higher in the trained adult racehorses. There was a more rapid decrease in venous lactate and a more rapid return to initial R values in the adult horses relative to the younger, untrained horses. No significant age or training effects were found in the remainder of the post exercise measurements. These results indicate that aerobic power and exercise capacity increased with age and training. Anaerobic power was already well developed even at a young age.     

Mechanical properties of excised calf lungs

Five isolated calf lungs were suspended in an airtight box used as a ventilator. Lungs were ventilated from the outside at different levels of transpulmonary pressure (Ptp). The static pressure-volume curve characteristics of the lungs were measured. Static compliance (Cstat) was 1.9 +/- 0.37 litres kPa-1 or 25 +/- 5 per cent of total lung capacity kPa-1. At a Ptp of 0.7 kPa, dynamic compliance (Cdyn) and lung resistance (RL) were 1.1 +/- 0.1 litres kPa-1 and 0.126 +/- 0.02 kPa litres sec-1, respectively. Both an increase and a decrease of this level of Ptp induced an increase of RL and a decrease of Cdyn. The ratio Cdyn/Cstat averaged 57 +/- 0.8 per cent. It was concluded that in excised lungs, Cdyn is lower in the calf than in a number of other species and that pulmonary function values measured in vitro are optimum at values of Ptp close to values recorded in vivo in healthy cattle.     

Efficacy and safety of cefovecin (Convenia) for the treatment of urinary tract infections in dogs

OBJECTIVES: To determine the efficacy and safety of cefovecin (Convenia); Pfizer Animal Health) in the treatment of urinary tract infections in dogs. METHODS: A multi-centre, blinded, randomised study was conducted in 129 dogs with urinary tract infections. Cephalexin (Rilexine) administered twice daily at 15 mg/kg bodyweight orally for 14 days was compared with a single, subcutaneous injection of cefovecin (Convenia) in dogs. The primary efficacy parameter assessed was bacterial elimination of the pretreatment uropathogen. RESULTS: One hundred and twenty-nine dogs were included in efficacy assessments. Escherichia coli was eliminated in 90.5 per cent of cefovecin-treated dogs compared with 52.9 per cent of cephalexin-treated dogs (P=0.0004). Overall cure rates for dogs with Escherichia coli infections were 79.1 per cent for cefovecin and 36.4 per cent for cephalexin-treated dogs (P=0.0003). There were no suspected adverse drug reactions attributed to treatment with cefovecin or cephalexin. CLINICAL SIGNIFICANCE: Cefovecin was shown to be an effective and safe treatment for urinary tract infections.     

Pharmacokinetics of marbofloxacin in blue and gold macaws (Ara ararauna)

OBJECTIVE: To determine the pharmacokinetics of marbofloxacin after single IV and orally administered doses in blue and gold macaws. ANIMALS: 10 healthy blue and gold macaws. PROCEDURES: In a crossover study, marbofloxacin (2.5 mg/kg) was administered orally (via crop gavage) to 5 birds and IV to 5 birds. Blood samples were obtained at 0, 0.5, 1, 3, 6, 12, 24, 48, 72, and 96 hours after marbofloxacin administration. After a 4-week washout period, the study was repeated, with the first 5 birds receiving the dose IV and the second 5 birds receiving the dose orally. Serum marbofloxacin concentrations were quantitated by use of a validated liquid chromatography-mass spectrometry assay. RESULTS: After oral administration, mean +/- SD area under the curve was 7.94 +/- 2.08 microg.h/mL, maximum plasma concentration was 1.08 +/- 0.316 microg/mL, and bioavailability was 90.0 +/- 31%. After IV administration of marbofloxacin, the apparent volume of distribution was 1.3 +/- 0.32 L/kg, plasma clearance was 0.29 +/- 0.078 L/h/kg, area under the curve was 9.41 +/- 2.84 microg.h/mL, and the harmonic mean terminal half-life was 4.3 hours. CONCLUSIONS AND CLINICAL RELEVANCE: Single IV and orally administered doses of marbofloxacin were well tolerated by blue and gold macaws. The orally administered dose was well absorbed. Administration of marbofloxacin at a dosage of 2.5 mg/kg, PO, every 24 hours may be appropriate to control bacterial infections susceptible to marbofloxacin in this species.