This study investigates the frequency of different stages of spermatogenic cycle in synthetic bulls, being 12 from Braford and 8 from Brangus-Ibagé breed with normal and altered semen quality, classified as sound (Group A) and unsound (Group B) animals by andrological examination. The staging criteria includes the proliferative (stage I), meiotic (stage II) and the maturation (stage III) periods of the spermatogenesis. The Braford bulls present different frequencies between groups within stages II and III. Among Brangus-Ibagé bulls there are different frequencies between groups just for stage II. The results indicate that spermatogenesis progress adequately in the stage I on synthetic bulls with different semen quality. During the period in which meiotic divisions (stage II) and spermatid maturation (stage III) occur there are disturbs in the spermatogenesis of the unsound bulls. The present proposition to cluster the stages of the spermatogenic cycle, forgives a practical method to evaluate the dynamic of germinative epithelium in bulls with different breeding soundness classification.
staging; spermatogenesis; synthetic bulls
