HORMONAL PROTOCOLS AND REPRODUCTIVE EFFICIENCY IN FIXED-TIME ARTIFICIAL INSEMINATION (FTAI) IN ANIMALS

Abstract

Fixed-Time Artificial Insemination (FTAI) represents one of the main biotechnologies applied to bovine reproduction, contributing to genetic improvement, increased productive efficiency, and optimization of reproductive herd management. The present study aimed to review the main hormonal protocols used in FTAI and the factors influencing reproductive efficiency in cattle. This is a narrative literature review developed from scientific articles published over the last fifteen years and indexed in the PubMed database. The results demonstrate that hormonal protocols based on GnRH, estradiol, progesterone, and equine chorionic gonadotropin (eCG) promote ovulation synchronization and improve pregnancy rates, especially when associated with proper animal management. Furthermore, factors such as body condition score, heat stress, nutritional status, herd health, and technical training of professionals directly influence reproductive outcomes. Recent studies also highlight the potential use of molecular biomarkers as auxiliary tools for early pregnancy assessment. It is concluded that the association between efficient hormonal protocols, appropriate sanitary and nutritional management, and biotechnological advances is essential to maximize reproductive performance in FTAI.