Durata del calore (intertempo fra il suo inizio e la sua fine) ed ovulazione nella bifala in funzione del momento stagionale: confronto tra estri spontanei e indotti con alfaprostol

From the end of November to the middle of April, heats duration and ovulation ways were studied on 70 buffalo cows kept apart from bulls. Resultsd referred to 324 spontaneous heats and 102 inducted by Alfaprostol. It was found a mutual relation between heats duration and ovulation time either in controls (r=0.59***). During the months characterized by a decrease of reproductive activity it is necessary to use both progesterone determination in milk and prostaglandine administration. Trough these devices a greater number of useful ovulations can be obtained in 48Hrs. In December, when the reproductive activity is more favourable, Alfaprostol administration proved to be useful considering it alowed to operate also in case of silent heats, which occur frequently (34.3% of spontaneous heats observed) during this period.