Autoclaved, previously used intravaginal progesterone devices induces estrus and ovulation in anestrous Toggenburg goats
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Data
2011-11-01
Autores
Souza, J. M. G.
Torres, C. A. A.
Maia, A. L. R. S.
Brandao, F. Z.
Bruschi, J. H.
Viana, J. H. M.
Oba, Eunice [UNESP]
Fonseca, J. F.
Título da Revista
ISSN da Revista
Título de Volume
Editor
Elsevier B.V.
Resumo
Intravaginal progesterone devices are used worldwide for estrus induction in goats. Reused devices are able to induce estrus; however, this can be a health risk within a flock. The objective was to compare new and previously used (and autoclaved) progesterone-releasing intravaginal devices for induction of estrus and ovulation in seasonally anestrous Toggenburg goats. Anestrous goats (n = 42) received new intravaginal devices containing 0.3 g progesterone (CONTROL), or similar devices previously used for either 6 (USED6) or 12d (USED12) and subsequently autoclaved. All goats received 5 mg dinoprost at device insertion and 200 IU eCG 5 d later, and all devices were removed after 6 d. After device removal, estrus was monitored and females displaying signs of estrus were mated by fertile bucks. Transrectal ovarian ultrasonography was performed after device removal until detection of ovulation. Blood samples were collected for determination of plasma progesterone concentration at different times. There was no difference (P > 0.05) among groups CONTROL, USED6 or USED12 for: estrus response (87,100 or 100%, respectively); duration of estrus (32.3 +/- 2.3, 25.2 +/- 3.4 or 27.3 +/- 4.1 h); ovulation rate (100,88 or 100%); number of ovulations (1.5 +/- 0.2, 1.9 +/- 0.3 or 1.7 +/- 0.3); and pregnancy rate (60, 58 or 67%). Plasma progesterone (P4) concentrations were greater (P < 0.05) in CONTROL than in USED6-treated and USED12-treated goats (7.2 +/- 1.2, 4.7 +/- 0.7 and 4.3 +/- 0.6 ng/mL, respectively) at 6h after device insertion; these differences were maintained until 4d after device insertion (3.4 +/- 0.4, 2.3 +/- 0.2, and 2.5 +/- 0.2 ng/mL). Overall, plasma progesterone concentrations were greater (P < 0.05) in nulliparous than in lactating goats (3.1 +/- 0.8 compared to 2.4 +/- 0.6 ng/mL, respectively). In conclusion, autoclaved, previously used intravaginal progesterone-releasing devices resulted in significant lesser plasma progesterone concentrations than new devices, but were similarly effective in inducing estrus and ovulation in anestrous goats. (C) 2011 Elsevier B.V. All rights reserved.
Descrição
Palavras-chave
Goats, CIDR, Estrus induction, Ovarian follicular dynamics, Seasonal anestrus
Como citar
Animal Reproduction Science. Amsterdam: Elsevier B.V., v. 129, n. 1-2, p. 50-55, 2011.