Abstract
Objective—To determine whether 4 mg of estradiol cypionate (ECP) administered prophylactically to highrisk postparturient dairy cows decreases incidence of postpartum metritis.
Design—Randomized, placebo-controlled, triplemasked clinical trial.
Animals—250 postparturient dairy cows in a herd with postparturient hypocalcemia, retained fetal membranes, dystocia, stillbirth, or twins.
Procedure—Cows were given 4 mg of ECP (treatment) or 2 mL of vegetable oil (control) by IM injection within 24 to 36 hours of calving. Monitoring rectal temperatures and evaluation for metritis was performed once daily for 10 days. Cows with fever ≥ 39.7°C (103.5°F) were treated with 1.5 g of ceftiofur hydrochloride.
Results—When assessed by ordinal logistic regression, there were no differences between groups in incidence of mild or severe metritis. Cows that calved during the second or third quarter of the year were at increased risk of metritis, compared with those that calved during the fourth quarter. Following stratification by lactation (first and ≥ 2), it was observed that multiparous cows that did not receive antimicrobials during the first 3 days of the postparturient period were 5 times as likely to have metritis, compared with cows treated with antimicrobials on the basis of fever or other concurrent disease.
Conclusions and Clinical Relevance—Prophylactic administration of ECP to dairy cows at high risk for metritis did not reduce risk for metritis. Treating multiparous cows with antimicrobials on the basis of fever during the early postpartum period was associated with decreased incidence of metritis. (J Am Vet Med Assoc 2003;223:846–851)