UTILIZATION OF PHYSICALLY EFFECTED FIBER (PEF) IN DAIRY COW

This review aims to provide a comprehensive understanding of the role of physically effective fiber (PEF), or peNDF, in the nutrition and rumen physiology of dairy cows. It investigates the physiological significance of fiber in dairy cow diets, stating its role in stimulating rumination, promoting saliva production, and maintaining optimal rumen pH. Factors influencing PEF requirements, including diet composition, feeding practices, and cow physiology, are thoroughly examined. Furthermore, the review discusses methods for measuring PEF and assessing its effectiveness in dairy diets, alongside the challenges associated with quantifying fiber effectiveness are addressed, shedding light on cases of fiber assessment in practical feeding scenarios. It investigates theeffects of PEF on rumen function, dairy cow performance, and the prevention of metabolic disorders such as subacute ruminal acidosis (SARA) providing insights into its crucial role in enhancing nutrient utilization, and overall animal health economic and environmental implications of formulating diets to meet PEF targets. It underscores the potential benefits for both farm profitability and environmental sustainability, emphasizing the significance of optimizing fiber levels to enhance nutrient utilization and minimize the environmental footprint of dairy production systems.