Comparative analysis of vocalizations of thoroughbred mares (Equus caballus) between estrus and diestrus.

We investigated the differences between vocalizations of mares in estrus and diestrus and determined the spectrographic parameters to discriminate estrus from diestrus. Thoroughbred brood mares (n=89) were exposed to a teasing procedure for 3 min, and we recorded all vocalizations emitted from them. Among the mares, 56.