Sustain performance while removing zinc oxide from the diet

Introduction

Weaning is a stressful period during swine production, which can render piglets susceptible to physiological and pathological imbalances of the gastro-intestinal functionality and can lead to post-weaning diarrhea (PWD). For more than 30 years, the use of zinc oxide (ZnO) has been a common practice in pig production throughout the world to prevent PWD in piglets.

However, after all these years of use, the mechanisms by which ZnO can effectively prevent diarrhea have still not been completely elucidated. This may be due to the polyvalent nature of the working mechanism in the gut of piglets. Microbiota modulation is thought to be one of the main pathways by which ZnO helps control PWD. It seems ZnO acts by increasing the microbiota diversity of the gut, thereby creating competition with the colonization of E. coli, the main cause of PWD. But other modes of action have also been described, such as the reduction of intestinal paracellular permeability, the activation of local immune cells and the regulation of anti-inflammatory cytokines.