Differential Estradiol Requirement for the Induction of Estrus Behavior and the Luteinizing Hormone Surge in Two Breeds of Sheep1
| Autor: | S. Ben Saïd, S. Canepa, C. Fabre-Nys, C. Briant, Alain Caraty, Didier Lomet, D. Guillaume, D. Chesneau, L. Lardic |
|---|---|
| Přispěvatelé: | Physiologie de la reproduction et des comportements [Nouzilly] (PRC), Institut National de la Recherche Agronomique (INRA)-Institut Français du Cheval et de l'Equitation [Saumur]-Université de Tours-Centre National de la Recherche Scientifique (CNRS), Institut Français du Cheval et de l'Equitation [Saumur]-Université de Tours-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire des Mécanismes et Transfert en Géologie (LMTG), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Recherches Cunicoles (SRC), Institut National de la Recherche Agronomique (INRA) |
| Rok vydání: | 2007 |
| Předmět: |
medicine.medical_specialty
Ile de france medicine.drug_class [SDV]Life Sciences [q-bio] media_common.quotation_subject Biology [SCCO]Cognitive science 03 medical and health sciences 0302 clinical medicine Internal medicine medicine Ovulation ComputingMilieux_MISCELLANEOUS 030304 developmental biology media_common Estrous cycle 0303 health sciences 030219 obstetrics & reproductive medicine Cell Biology General Medicine Breed Endocrinology Reproductive Medicine Hypothalamus Estrogen Ovariectomized rat Luteinizing hormone |
| Zdroj: | Biology of Reproduction Biology of Reproduction, Society for the Study of Reproduction, 2007, 76 (4), pp.673-680. ⟨10.1095/biolreprod.106.057406⟩ |
| ISSN: | 1529-7268 0006-3363 |
| DOI: | 10.1095/biolreprod.106.057406 |
| Popis: | For a better understanding of the mechanisms that lead to the preovulatory GnRH/LH surge and estrus behavior, the minimum estradiol (E) requirements (dose and duration) to induce each of these events were determined and compared between two breeds of ewes having either single (Ile de France) or multiple (Romanov) ovulations. The ewes were initially studied during a natural estrus cycle, and were then ovariectomized and run through successive artificial estrus cycles. For these artificial cycles the duration and amplitude of the follucular phase E increase were manipulated by E implants. Under all conditions, the onset of estrus behavior was similar in the two breeds, although its duration was longer in Romanov ewes. While a moderate E signal (6 cm for 12 h) induced an LH surge in 10/10 Ile de France ewes, a larger E signal (12 cm for 12 h) was minimally effective in Romanov ewes (4/10). Additional studies revealed that a small E signal (3 cm for 6 h) induced full estrus behavior in all Romanov ewes but was completely ineffective in Ile de France animals (0/10). Higher doses and mostly longer durations of the E signal (12 cm for 24 h) were required to induce a surge in all the Romanov ewes. These results demonstrate a clear difference in the E requirement for the induction of estrus behavior and the LH surge between breeds of ewes that have different ovulation rates. These data provide compelling evidence that, in one breed, the neuronal systems that regulate both events require different estrogen signals. |
| Databáze: | OpenAIRE |
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