Our understanding of dietary fiber in sow nutrition is evolving rapidly, shifting from a once-overlooked portion of the diet to a critical component influencing intestinal functionality, gut microbiota, and modulation of digestion and metabolism. Recent advancements in fiber nutrition and analytical methods have highlighted its significance in optimizing sow lifetime productivity and welfare through its impact on nutrient utilization and overall health. Growing evidence supports the benefits of dietary fiber in gestation diets, notably contributing to sow well-being by reducing stress and behavioral issues observed in group housing systems (Sapkota et al., 2016). Accordingly, dietary fiber supplementation in gestation diets has been linked to the reduction of stillborn pigs, heavier piglet weights at birth, increased lactation feed intake, and reduced pre-wean mortality (Feyera et al., 2017). Supplementing dietary fiber during the peripartum phase has been shown to reduce the farrowing duration and the stillborn incidence (Theil et al., 2014); possibly linked to a reduction in constipation (Cardona et al., 2024) and enhanced sow energy status through greater short-chain fatty acids availability (Feyera et al., 2017). Despite the positive evidence, the practical application of dietary fiber supplementation in US sow diets has been limited due to insufficient characterization of fiber components in available ingredients. Recent advancements in analytical techniques, defining fiber components as total dietary fiber (TDF), soluble fiber (SF), and insoluble fiber (ISF), offer improved reliability and accessibility, overcoming previous barriers. Recent studies showed that a high fiber gestation diet (TDF 18% and 9% for high and low fiber diets, respectively) did not affect reproductive performance, liter size, individual piglet weight, or pre-wean mortality but it reduced weight loss during lactation (Paz et al., 2022). Moreover, studies conducted by Martinez et al. (2022) demonstrated that top-dressing dietary fiber during the peripartum phase reduced the wean-to-estrus interval (top-dress 0.45 kg or 0.90 kg/day, TDF 35%, ISF:SF ratios ranging from 2.6 to 7.4).
These studies highlight the potential value of dietary fiber in US sow diets. However further research is warranted to determine the optimal level and desirable fiber characteristics to fully unlock its nutritional value in sow diets.