A method for inducing the onset of the reproductive cycle of female breeding animals is provided. To this end, the animals are injected with an agent that contains synthetically produced FSH releasing hormones as the active substance which comprise known sequences, consisting of 10 amino acids (decapeptide). The active substances are administered to the animals in the form of solution 0 to 96 hours after termination of the preceding anestrus or inhibition or a biotechnical treatment. The agents used promote an onset of the reproductive cycle after the young animals have been weaned from the mature animals and a synchronization of heat in animals that are to be inseminated for the first time.
