Effect of the administration of flunixin meglumine on pregnancy rates in Holstein heifers

Fifty-two 15-month-old Holstein heifers were synchronised with single or double injections of prostaglandin F(2alpha), followed by an injection of gonadotrophin-releasing hormone (gnrh) 48 hours later, and inseminated 12 to 14 hours after the injection of gnrh (day 0). Half of them were then injected twice intramuscularly with 1.1 mg/kg flunixin meglumine 12 hours apart, on the evening of day 15 and the morning of day 16, and the other 26 were not treated. Pregnancy was diagnosed by ultrasound 29 and 65 days after they were inseminated. On day 29, 20 of the treated heifers were pregnant compared with 13 of the control heifers (P<0.05); on day 65, 18 of the treated heifers were still pregnant compared with 12 of the control heifers (P<0.10).