Pharmacokinetics of penicillin‐G in ewes and cows in late pregnancy and in early lactation

Abstract

Concentrations of penicillin-G in serum were determined after single intravenous doses of potassium penicillin-G (10 mg/kg body wt) to ewes and cows in late pregnancy and in early lactation. Penicillin-G in serum was analysed by a microbiological method and pharmacokinetic parameters were calculated by model-independent methods. Serum concentrations were lower in early lactation than in late pregnancy in both ewes and cows. The differences were statistically significant at most sampling times in ewes but only during the first hour in cows. Weight corrected values of clearance and volume of distribution were significantly higher in early lactation than in late pregnancy in both ewes and cows. Mean residence time and elimination-half life were shorter in lactating than in pregnant ewes, however for the latter parameter the difference was not statistically significant. Neither of these parameters changed in cows. It is concluded that in both ewes and cows pharmacokinetic parameters of penicillin-G are altered from late pregnancy to early lactation but that these changes have little practical impact and do not call for a revised dosage regime of the studied drug.

Interspecies Mixed-Effect Pharmacokinetic Modeling of Penicillin G in Cattle and Swine

“…Ranheim et al reported that the clearance of penicillin was lower in 1-week-old piglets than in adult pigs (7,51). Musser et al found that the volume of distribution at steady state (V ss ) of the calf was significantly higher than that of adult cattle (5,30). The use of adult data only may not be able to describe all of the PK characteristics of penicillin G. Thus, we combined data from a wide range of weights and ages by adding them as covariates in order to illustrate their relationships with the basic PK parameters.…”

Pharmacodynamics of Antimicrobials against Mycoplasma mycoides mycoides Small Colony, the Causative Agent of Contagious Bovine Pleuropneumonia

“…Although most changes in PK seem to occur between newborn pre-ruminant and ruminating stages [43], [44], it is possible that age-related PK changes exist between calves and adult cattle, as observed in the human population [45]. Furthermore, PK parameters may be influenced by gender [46], physiological status [47], breed of cattle [48], or indeed the species (i.e. Bos taurus versus Bos indicus ).…”

Bioavailability and disposition of sodium and procaine penicillin G (benzylpenicillin) administered orally with milk to calves

“…The other kinetic parameters of sodium penicillin G were similar to cattle following i.v. administration (Soback et al ., 1987; Volner et al ., 1987; Bengtsson et al ., 1997) and displayed the typical characteristics of the penicillin family of antibiotics. These characteristics include a rapid distribution phase, short half‐life of elimination, and Vd SS indicative of distribution to the vascular and the extracellular fluid (Riviere et al ., 1991).…”