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Equine body temperature and progesterone fluctuations during estrus and near parturition
S F Ammons1, W R Threlfall, R C Kline
1Department of Animal Science The Ohio State University Columbus, OH 43210 USA; Department of Veterinary Clinical Sciences The Ohio State University Columbus, OH 43210 USA.
Abstract:
Body temperature and serum progesterone concentrations were measured in mares to determine if a change in either could be useful in predicting estrus, ovulation or parturition. There was no significant correlation (P > 0.1) between rectal temperature and the environmental temperature or progesterone concentration. Progesterone concentration did correlate with stage of estrous cycle and the stage of pregnancy. Significant differences (P < 0.05) in temperature were noted at different times throughout the day. No change in temperature occurred that could be utilized to predict estrus, ovulation or parturition. The changes in serum progesterone concentration were only useful in detecting estrus.
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