Comparing the pharmacokinetics of a fourth generation cephalosporin in three different age groups of New Forest ponies.

The research compares the effects and performance of a specific antibiotic drug, cefquinome, in New Forest ponies of different ages. The study aimed to provide beneficial dosage recommendations for the treatment of various infections.

Methodology

• The ponies were divided into three age groups: neonatal foals, 6-week-old foals, and mature ponies. Each group had six ponies.
• The drug, cefquinome, was administered to each group in varying frequencies and dosages. The dosages ranged from 1 mg/kg body weight twice a day, three times a day, and a higher dose of 4.5 mg/kg twice a day.
• The concentration of cefquinome in the ponies’ plasma was analyzed using a method called high-performance liquid chromatography combined with electrospray tandem mass spectrometry.

Results

• The results revealed that the two foal age groups had similar pharmacokinetic data, except for certain parameters: volume of distribution at a steady-state, total body clearance, and mean residence time.
• It was observed that as the foals grew older, both the total body clearance and mean residence time decreased.
• The area under the curve values, which measure the overall drug exposure over time, increased in a dose-dependent manner. This increase was significant for all age groups when the dosage was at its highest (4.5 mg/kg twice a day).
• However, total body clearance did not show the same dose dependency as the area under the curve values.

Conclusions

• The research suggests that cefquinome can be administered at a dose of 1 mg/kg body weight twice a day for treating infections caused by certain pathogens with minimum inhibitory concentration (MIC) less than 0.125 micrograms/ml.
• The research also recommends a higher dose of 4.5 mg/kg body weight twice a day to treat bacterial pathogens with MIC between 0.125 and 0.5 micrograms/ml.
• The research concludes that dosing regimens commonly used should be critically reviewed for neonatal foals due to the higher volume of distribution of less lipophilic drugs in this age group.