A 2-year-old 14.7-kg (32.3-lb) sexually intact female Australian Shepherd was referred to the Louisiana State University Veterinary Teaching Hospital (LSU VTH) Theriogenology Service for evaluation because of a 1-week history of anorexia and vomiting and a 7-week history of serosanguineous discharge from the vulva since preterm labor and delivery (50 days after mating) of 9 stillborn pups, with 3 pups delivered vaginally and the remaining 6 pups delivered by cesarean section performed by the referring veterinarian. Postmortem examination of the fetuses was not performed, and the reason for the preterm labor was not further investigated. The referring veterinarian had
OBJECTIVE To evaluate use of flunixin meglumine as a treatment to postpone ovulation in mares, mare fertility after flunixin meglumine treatment during estrous cycles, and effects of flunixin meglumine on function of the corpus luteum after ovulation.
ANIMALS 13 healthy mares.
PROCEDURES A single-blinded, placebo-controlled, crossover study was conducted. Flunixin meglumine (1.1 mg/kg, IV, q 24 h) or lactated Ringer solution (placebo treatment) was administered for 2 days to mares with a dominant follicle (≥ 35 mm in diameter) and behavioral signs of estrus. Mares then were bred by artificial insemination. Number of days to ovulation from initial detection of a follicle ≥ 30 mm in diameter, uterine edema score, and pregnancy were determined by ultrasonography; the examiner was unaware of the treatment of each mare. Serum progesterone concentrations were evaluated 5 and 12 days after ovulation by use of radioimmunoassay.
RESULTS Data were available for 45 estrus cycles of the 13 mares. Number of days to ovulation from initial detection of a follicle ≥ 30 mm was not significantly affected by administration of flunixin meglumine versus the placebo. Per-cycle pregnancy rate was not significantly different between flunixin meglumine (20/24 [83%] breedings) and the placebo (13/19 [68%] breedings). Flunixin meglumine did not significantly affect behavioral signs of estrus, uterine edema, or serum progesterone concentrations.
CONCLUSIONS AND CLINICAL RELEVANCE Findings did not support the use of flunixin meglumine to postpone ovulation in mares.