Tel.+49 30 838 62618 Fax.+49 30 838 62620
The systemic application of ceftiofur has been demonstrated as efficacious for the treatment of retained fetal membranes (RFM) and acute metritis in dairy cows.
The objective of this study was to determine the concentration of ceftiofur after subcutaneous (s.c.) application in cows with RFM in blood serum and uterine tissues
(caruncles, endometrium) over a period of 3 days. After induction of parturition between 265 to 275 days of gestation, two primiparous and four multiparous cows that retained their fetal membranes for at least 12 h were included in the study. All cows received ceftiofur (1 mg/kg, s.c.) within 48 h after calving (C1) and again 24 h (C2) and
48 h (C3) after the initial application. Samples of blood and uterine tissues were collected immediately before C1 and 2, 4, 12, and 24 h after C1, C2 and C3, respectively. At the time of application C2 and C3, samples were collected immediately before treatment. Blood samples were taken from the coccygeal vessels. Caruncles were removed from the uterine cavity by manual and separated from cotyledons. Endometrial tissue (0.5 g) was collected by using a biopsy apparatus. Serum and endometrial tissues were stored at –20C until analysis. For each cow and sample, the concentrations of potentially active ceftiofur derivates in the biological matrices were quantified using a high-performance liquid chromatography (HPLC) assay.
Within 4 h (serum, endometrium) and 12 h (caruncles) after C1 and for the entire study period, concentration of ceftiofur derivates exceeded reported MIC90 values for relevant bacteria E. coli, F. necrophorum, and A. pyogenes. In two (serum) and one (caruncle,
endometrium) cows, concentrations decreased below MIC90 for E. coli at 24 and 48 h after C1, but increased within 2 h after C2 and C3 above MIC90.