Alternative low doses and routes of administering a prostaglandin F2alpha analogue to induce luteolysis in Nelore cows.
- Author:
Cezinande MEIRA
1
;
Valsair Matos PESSOA
;
Joao Carlos Pinheiro FERREIRA
;
Gustavo Henrique M ARAUJO
;
Marilu M GIOSO
;
Sony Dimas BICUDO
;
Eunice OBA
;
Cassia ORLANDI
Author Information
- Publication Type:Original Article ; Randomized Controlled Trial ; Research Support, Non-U.S. Gov't
- Keywords: Bai-hui acupoint; cows; luprostiol; luteolysis; progesterone; prostaglandin
- MeSH: Acupuncture; Animals; Cattle/*physiology; Dose-Response Relationship, Drug; Female; Injections, Intramuscular/veterinary; Luteolysis/*drug effects; Progesterone/blood; Prostaglandins F, Synthetic/*administration & dosage
- From:Journal of Veterinary Science 2006;7(4):387-390
- CountryRepublic of Korea
- Language:English
- Abstract: The present study was conducted in order to verify the efficacy of lower doses and alternative routes of a prostaglandin F2 alpha analogue, luprostiol (PGF), for the induction of luteolysis and the precipitation of estrus in nonlactating Nelore cows (Bos taurus indicus). A conventional dose (15 mg) of PGF was compared to doses lower than the conventional dose, which ranges from 10 to 50%, that were administered intramuscularly (IM), intravulvosubmucosally (IVSM), or in the Bai-hui acupuncture site located within the lumbosacral area. The cows were administered PGF 8 day after estrus in the presence of a corpus luteum, and randomly assigned to the following groups: G1 (positive control), 15 mg, IM (n = 23); G2, 7.5 mg, IM (n = 23); G3, 3.75 mg, IM (n = 24); G4, 7.5 mg, IVSM (n = 25); G5, 3.75 mg, Bai-hui acupoint (n = 24); and G6, 1.5 mg, Bai-hui acupoint (n = 25). The results indicated that 50% of a conventional dose of PGF (7.5 mg) resulted in a complete luteal regression (plasma progesterone <1 ng/ml) at Hour 48, and hastened estrus, regardless of whether or not PGF was administered IM or IVSM. Comparatively, 10 or 25% of the conventional dose, even when administered to the Bai-hui acupoint, resulted in an initial reduction in the concentration of progesterone at Hour 24, followed by an increase observed at Hour 48. In conclusion, 25% of a conventional PGF dose administered via the Bai-hui acupoint proved inadequate to induce a complete luteal regression, whereas 50% of a conventional dose administered IM or IVSM was found to be the minimal dose required to induce effectively a complete luteal regression, and to precipitate the onset of estrus in nonlactating Nelore cows.
