The pharmacokinetic parameters of ketoprofen have previously been studied in cattle, but no studies have been performed on differing ages and metabolic situations in these animals. The aim of this work was to study the possible modifictions of the pharmacokinetics of ketoprofen enantiomers that may result from age, lactation or gestation in dairy cattle. Three groups of Holando Argentino cattle contained, respectively, 8 cows in early lactation, 8 pregnant cows and 8 newborn calves. Four animals from each group received the enantiomer R-(-)-ketoprofen, the other four animals received the S-(+) enantiomer, all by intravenous injection at a dose of 0.5 mg/kg. Significant differences between the three categories of animals were obtained in elimination half-life (t1/2) (1.52, 0.87 and 0.31 and 1.71, 0.69 and 0.26 in newborn calves, cows in early lactation and cows in gestation, respectively), mean residence time (MRT) (0.45, 1.25, 2.20 and 0.38, 0.99, 2.47 h, in cows in gestation, cows in early lactation and newborn calves, respectively) and area under the plasma concentration-time curve (AUC) (0.87, 2.93, 3.24, and 0.67, 2.78, 5.13 (microg/h)/ml in cows in gestation, cows in early lactation and newborn calves, respectively, for the R-(-) and S-(+) enantiomer, respectively. In calves, there was a significant difference in AUC (3.24 vs 5.13 (microg/h)/ml between R-(-)- and S-(+)-ketoprofen. In view of the differences between calves and adult cattle in the pharmacokinetic results for ketoprofen, the effects of age and physiological status (lactation, gestation) should be taken into account for therapeutic regimens.

The aim of the study was to evaluate the pharmacokinetics of flurbiprofen (FBP) in different age groups and physiological status groups in dairy cattle. Ten Argentine Holstein bovines were divided into three different groups: 3 cows in early lactation, 3 cows in gestation and 4 newborn calves. Based on previous experience, all the animals received racemic FBP (50:50) at a dose of 0.5 mg/kg by intravenous administration. Blood samples were taken at predetermined times after administration of flurbiprofen. Plasma enantiomer concentrations were measured by HPLC. Total body clearance (ClB) of (S)-(+)-FBP was higher in calves than in cows (114.5, 136.4, 121.4, 128.9 microg/ml vs 22.0, 24.2, 46.5 microg/ml and 27.6, 25.3, 34.6 microg/ml). In calves the disposition kinetics showed stereoselective behaviour. Area under the concentration-time curve (AUC) was higher and Cl(B) and steady-state volume of distribution (V(ss)) were lower for (R)-(-)-FBP than for (S)-(+)-FBP. In cows, stereoselectivity was observed in Cl(B) and elimination half-life (t(1)/2) only in the early lactation group. In this study, enantioselective metabolic behaviour of FBP under the physiological situations studied was found. Hence, it is possible that both enantiomers of flurbiprofen may contribute to the drug's therapeutic effects, but further studies with the administration of separate enantiomers will be required to elucidate their metabolism.

Experiment was designed to assess alimentary security or any beneficial effect on calve of a multispecies multistrain probiotic (MMP). An experiment with 36 calves, two day old, was conducted to assess the influence of probiotic on growth and health indicators. The treatment period was extended to 45 d. Group 1 received one daily dose of MMP (1.1 × 10 9 CFU per calf) during 20 d. Group 2 was the untreated control. On a weekly basis, every calf in each group was weighed to determine weight gain. Forty five days after the beginning of the experiment, blood samples were obtained from seven animals from Group 1 and six from Group 2, and peripheral blood neutrophils separated in order to determine metabolic and microbicidal activity. There was a significant increase in H 2 O 2 production and NBT reduction test in MMP treated calves. The MMP not only lacks adverse effects when supplied as food additive, but showed health benefits. The prevention of infection and the highly significant increase of phagocytic activity in peripheral blood leukocytes seen in calves strongly suggest an efficient connection between the MMP and the immune system.

The aims of this work were: To achieve a simple and low cost propagation of potential probiotic agents using plain whey as a culture medium, study the diversity of the members of the bacterial community (MC) in plain whey and to evaluate the probiotic capacity of this MC. After a systematic selection of agents according to their growing capacity in whey, the constituted MC was considered as a unit. Biochemical characterization of the lactic acid bacteria were performed using the API system. Molecular characterization of the lactic acid bacteria was realized using AFLP ™ DNA-fingerprinting, partial 16S rDNA sequence analysis and PCR-denaturing gradient gel electrophoresis (PCR-DGGE). The physiological characterization of yeast was determined with the automated microplate method Allev/Biolomics and using yeast characterization system based on standard taxonomic criteria. The identification molecular was realized by PCR-fingerprinting. The resistance of MC to pH and bile salts were evaluated. The MC was composed of agents from different separated Dominium like Bacteria (Lactobacillum) and Eukaria (yeast). They are multispecies and also multistrain assuring high biodiversity. The MC grew at low pH and different concentrations bile salts.

The chiral inversion of ketoprofen has been previously demonstrated in cattle, but no studies have been performed on different ages and metabolic situations in the animals. The aim of this work was to study any modifications of the stereoconversion of ketoprofen that occur by reason of age, lactation or gestation in dairy cows. Holando Argentino cattle were divided into three groups: 8 cows in early lactation, 8 pregnant cows and 8 newborn calves. Four animals from each group received the enantiomer R-(-)-ketoprofen by intravenous administration; the other four animals received the S-(+) enantiomer, all at doses of 0.5 mg/kg. Blood samples were collected at standardized times after dosing and assayed for ketoprofen by high-performance reversed-phase liquid chromatography (HPLC). The percentage inversion of R-(-)-ketoprofen to S-(+)-ketoprofen was 50.5% (SD +/- 2.4) in the preruminants, 33.3% (SD +/- 1.7) in cows in early lactation and 26.0% (SD +/- 5.1) in cows in gestation. These results indicate a differing enantioselective metabolic behaviour for one compound in one species under different physiological situations.