<b>Reproductive disorders in Simmental cattle: Enhancing fertility through a hormonal protocol</b>

Background: Reproductive disorders, including abortion, endometritis, and silent estrus, present significant challenges to fertility and productivity in Simmental cattle, particularly under semi-intensive farming systems. These conditions disrupt physiological and hormonal functions, impairing reproductive outcomes. Aim: This study aimed to evaluate the effectiveness of hormonal protocols in addressing these disorders by assessing reproductive tract size (RTS), cervical mucus characteristics, and fertility outcomes in cattle with varying reproductive health statuses. Methods: Healthy cattle exhibited optimal reproductive performance, characterized by high-quality cervical mucus, normal uterine horn dimensions, and superior fertility outcomes. This highlights the importance of balanced endocrine function in supporting optimal reproductive efficiency. Results: In contrast, cattle with abortion disorders and endometritis experienced disrupted uterine health, enlarged uterine horns, and diminished cervical mucus quality, resulting in significantly reduced fertility. Silent estrus cases showed intermediate results, reflecting suboptimal estrus expression and hormonal imbalances that affected reproductive efficiency despite hormonal interventions. Strong positive correlations were observed between cervical mucus characteristics such as viscosity, pH, and ferning patterns, and fertility outcomes, indicating their critical role in facilitating sperm survival, motility, and fertilization. Conversely, uterine horn dimensions exhibited a negative correlation with fertility, reflecting the impact of chronic inflammation and structural abnormalities on reproductive success. Conclusion: While hormonal protocols were effective in synchronizing estrus and inducing ovulation, their success varied depending on the severity of reproductive disorders and environmental management practices. These findings demonstrate that hormonal protocols can partially mitigate the physiological disruptions caused by reproductive disorders; however, integrated reproductive management strategies are essential. Combining hormonal interventions with targeted nutritional support, improved environmental management, and enhanced estrus detection practices is critical for optimizing reproductive performance. This study provides a framework for addressing reproductive challenges in Simmental cattle, supporting sustainable livestock production in semi-intensive systems and contributing to improved fertility outcomes in resource-limited settings.