Effect of the season on some aspects of the estrous cycle in Martina Franca donkey.
The Martina Franca (MF) donkey breed, with 48 jackasses and 515 jennies, is considered an endangered breed according to the data from the Monitoring Institute for Rare Breeds and Seeds in Europe. The knowledge of the estrous cycle characteristics has a great impact for assisted reproduction, especially in endangered species. In this study, the estrous cycle characteristics were investigated in 12 MF jennies throughout the year. Estrous cycle, estrous and diestrous lengths, follicular growth and ovulation, and estradiol-17β (E2) and progesterone (P4) plasma concentrations were monitored in MF jennies and compared in different seasons. In all jennies (100%) estrous cycle was detected during the whole year, with no differences in the estrous cycle length among seasons. However, a significant increase of estrous length in spring and summer compared with autumn and winter was found. Diestrus was shorter in summer than in the other seasons. Estrous behavior was always shown and characterized by rhythmic eversion of the vulvar labia (winking) with exhibition of the clitoris, urination, male receptivity and clapping, with sialorrhoea, neck and head extension, and back ears. Estrus was characterized by the ovulation of a larger follicle in spring and summer than in autumn and winter. The pattern of E2 and P4 plasma concentrations during the estrous cycle were similar to that reported for the mare, but without differences among the four seasons, so that a negligible effect of environmental conditions on ovarian E2 and P4 secretion was hypothesized, despite the larger diameter of the ovulating follicle in spring and summer.
Department of Veterinary Clinical Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy.
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Contri
Department of Veterinary Clinical Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy.
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Robbe
Department of Veterinary Clinical Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy. Electronic address: gloriaalessia@libero.it.
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Gloria
Department of Veterinary Clinical Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy.
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De Amicis
Department of Health, Animal Science and Food Safety, Faculty of Veterinary Medicine, Università degli Studi di Milano, Milan, Italy.
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Veronesi
Department of Veterinary Clinical Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy.
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Carluccio
D000818:Animals; D004031:Diestrus / Q000502:physiology; D056727:Endangered Species; D018397:Equidae / Q000502:physiology*; D004958:Estradiol / Q000097:blood; D030762:Estrous Cycle / Q000502:physiology*; D004971:Estrus / Q000502:physiology; D005260:Female; D008297:Male; D006080:Ovarian Follicle / Q000254:growth & development*; D010060:Ovulation / Q000502:physiology; D011374:Progesterone / Q000097:blood; D012098:Reproduction; D027724:Reproductive Techniques, Assisted / Q000662:veterinary; D012621:Seasons; D012726:Sexual Behavior, Animal; D013997:Time Factors
D011374:Progesterone; D004958:Estradiol
Donkey; Estrous behavior; Estrous cycle; Follicular dynamic; Ovulation