The use of slow-release nutrients in ruminant nutrition has emerged as a promising strategy to enhance efficiency and promote sustainability in livestock production systems. Unlike conventional nutrient sources that are rapidly degraded in the rumen, slow-release formulations provide a controlled, steady release of essential nutrients, such as nitrogen, amino acids, minerals, and vitamins. This steady supply supports optimal rumen microbial activity, improves nutrient utilization, and minimizes metabolic disturbances, leading to enhanced animal performance. Furthermore, slow-release nutrients reduce nutrient losses and environmental emissions by improving feed efficiency and lowering excretions of nitrogen and phosphorus, key pollutants in livestock operations. This review explores the mechanisms through which slow-release nutrients function in ruminants, their effects on health, productivity, and reproductive performance, and their role in reducing the environmental footprint of livestock farming. By integrating slow-release technologies, ruminant producers can achieve both economic benefits and improved sustainability, contributing to more efficient and environmentally friendly livestock production systems.

Keywords: Ruminant nutrition, livestock, microbial fermentation, encapsulation, controlled release of energy

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