dc.description.abstract | Several oestrus and ovulation synchronization programmes exist for dairy herds that include the use of different hormones like P4, PGF2α, GnRH and combinations of these hormones. Selection of a suitable synchronization protocol should be chosen on the basis of management capabilities and expectations of the farmer. Data collected from a Hungarian commercial dairy farm (n=3295) based on three hormonal synchronisation protocols (Ovsynch (n=135), Presynch (n=236) and G7G-Ovsynch (n=1162) and a spontaneous oestrus protocol (1700) was evaluated to reveal which protocol demonstrated the best pregnancy per artificial insemination rates and therefore which had the greatest reproductive efficiency. | en_US |