Effect of intrauterine administration of ceftiofur on fertility and risk of culling in postparturient cows with retained fetal membranes, twins, or both

OBJECTIVE: To determine the effect of intrauterine administration of ceftiofur sodium on fertility and the risk of culling in postparturient cows with retained fetal membranes (RFM), twins, or both. DESIGN: Single-blind randomized clinical trial and prospective cohort study. ANIMALS: 2442 cows that calved from January 1, 2000, to May 31, 2001. PROCEDURE: Cows with RFM, twins, or both were randomly allocated to control or treatment (ceftiofur) groups. Ceftiofur-group cows received 1 g of ceftiofur sodium sterile powder reconstituted with 20 mL of sterile water as a single intrauterine infusion once between 14 and 20 days after parturition. Control-group cows received no treatment. Cows that calved but did not have RFM or twins were considered the referent group. Reproductive, culling, and health data were recorded. RESULTS: There was no significant difference in the overall proportion of ceftiofur-group cows confirmed pregnant, compared with cows in the control group. Ceftiofur-group cows were significantly less likely to be culled and were culled at a later time in lactation than control-group cows. In the cohort study, the risk of pregnancy and the risk of being culled in ceftiofur-group cows were not significantly different from cows in the referent group. CONCLUSIONS AND CLINICAL RELEVANCE: Intrauterine treatment of cows with RFM, twins, or both with ceftiofur sodium increased longevity of cows in the herd as measured by the risk of culling and the time to culling. Intrauterine administration of ceftiofur in cattle is considered extralabel drug use, and the attending veterinarian must follow the AMDUCA guidelines for extralabel drug use.