Follicular dynamics in cattle

Abstract

Folliculogenesis is a complex and highly regulated process that governs the growth and maturation of ovarian follicles, ensuring successful ovulation and steroid hormone production. This review summarizes the stages of follicular development, including recruitment, selection, dominance, ovulation, and atresia, with emphasis on follicular wave dynamics in cattle. Follicular growth is regulated by the coordinated actions of follicle-stimulating hormone (FSH), luteinizing hormone (LH), granulosa and thecal cells, and local growth factors such as insulin-like growth factors (IGFs). The two-cell/two-gonadotropin model explains estradiol synthesis and the hormonal mechanisms underlying follicular selection and dominance. Changes in gene expression, steroid hormone concentrations, prostaglandin activity, and gonadotropin receptor regulation play crucial roles in ovulation and corpus luteum formation. Understanding these physiological and molecular mechanisms provides valuable insights for improving reproductive efficiency and developing advanced reproductive technologies in livestock.