Submitted to: Western Section of Animal Science Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 4/1/2003
Publication Date: 6/1/2003
Citation: MERRILL, M.L., ANSOTEGUI, R.P., WAMSLEY, N.E., BURNS, P.D., GEARY, T.W. EFFECTS OF FLUNIXIN MEGLUMINE ON EMBRYONIC LOSS IN STRESSED BEEF COWS. WESTERN SECTION OF ANIMAL SCIENCE PROCEEDINGS. 2003. v. 54. p. 53-55. Interpretive Summary: This study was designed to determine if an injection of flunixin meglumine (1.1 mg/kg) would reduce early embryonic mortality in stressed beef cows. Although there was a trend towards a reduction in embryonic mortality, it would be presumptuous to conclude a positive effect without further studies involving larger numbers of animals and more frequent blood collections to profile hormonal changes. At this time the mechanisms involved are unclear.
Technical Abstract: The objective of this study was to determine if flunixin meglumine reduces early embryonic death in cows subjected to stress. Approximately 14 d following synchronization of estrus and artificial insemination (AI), 97 cows were assigned to one of three treatments by AI sire, AI date, and AI technician. Treatments were control (CON), induced stress (S), and induced stress with flunixin meglumine (1.1mg/kg, i.m; SFM). Rectal temperatures were recorded and blood samples collected (caudal venipuncture) for measurement of cortisol, and PGF metabolite (PGFM) concentrations before and after induced stress. Control cows remained at the ranch with their calves and had access to water but not feed, while S and SFM cows were loaded on semi-trucks and transported for 4 h (mean ambient temperature 24 deg C). Cows were not exposed to clean-up bulls until after treatment. Transrectal ultrasonography was used to determine AI pregnancy status 55 to 57 d post AI. Pregnancy rates to AI tended (P = 0.17) to be higher among SFM cows (84%) than S cows (69%) while AI pregnancy rate of CON cows was intermediate (76%). Cortisol concentrations before and after treatment were 21 and 24 ng/ml, 23 and 17 ng/ml, and 18 and 8 ng/ml, for CON, S, and SFM cows, respectively. Change in cortisol concentration was different (P < 0.06) between CON and S or SFM, but not S versus SFM (P > 0.10). No changes (P > 0.10) in PGFM were detected among the three groups between the sampling periods. Body temperature decreased between the sampling periods for all treatments, but the change in temperature was greater (P < 0.03) for S and SFM cows compared CON. Across treatments, change in cortisol concentration between sampling periods did not influence (P > 0.10) AI pregnancy status, however, PGFM increased (P < 0.09) 24.72 pg/ml or decreased 5.19 pg/ml in cows diagnosed open or AI pregnant. In summary, flunixin meglumine appears to decrease the stress-induced embryonic loss, but the role of PGF and cortisol remain unclear.