Beyond Mineral Value: Why 'Superdosing' Phytase Is About Inositol, Not Just Phosphorus

The use of feed enzymes in monogastric nutrition has been a cornerstone of feed efficiency and environmental management for decades. However, a recent analysis suggests that the industry's long-held "scientific dogma" may be limiting the full potential of these additives. In an article on AB Vista's website titled "Enzymes through the ages: rethinking their use in animal nutrition," Mike Bedford (AB Vista) argues that the industry's focus on simple, measurable outcomes has created a reductionist view that needs challenging.

The article traces the history of enzyme use, from the first NSPases in the 1980s to tackle viscosity in barley-based diets, to the rise of phytase in the 1990s, which was driven more by environmental regulations on phosphorus output than by nutritional goals. This history, the author argues, has led to a perception of enzymes as commodities, optimized for cost savings or compliance rather than their full biological potential.

The central debate point raised is that the commercial use of phytase, which primarily targets the release of phosphorus from higher phytate esters (IP6 to IP3), is a significant missed opportunity. The text posits that a strategy of "superdosing" should not be seen as merely releasing more phosphorus, but as a method for the complete "dephytinisation" of the diet. This complete breakdown, including the lower esters (IP2 and IP1), is crucial for releasing inositol.

This is the key practical application: the generation of inositol, which is linked to significant metabolic advantages. Growing evidence suggests this enhanced inositol availability can improve protein digestibility, muscle protein synthesis, immune function, and—critically for fast-growing broilers—oxygen transport. This could provide a nutritional solution for biological challenges linked to poor oxygenation, such as woody breast myopathy and ascites, offering tangible welfare and performance benefits.

Similarly, the article calls for a re-evaluation of NSPases, moving beyond their interchangeable use for viscosity or cell wall breakdown. It highlights an emerging frontier in "stimbiotics"—specific oligosaccharides that can trigger beneficial microbial responses to modulate gut health and fermentation, rather than just acting as a bulk fiber source. The analysis concludes that phytases and NSPases are not finished technologies, and that by revisiting our assumptions, the industry can unlock a new level of animal health, welfare, and sustainability.