• Zinc oxide is commonly used in piglet diets to help control post-weaning diarrhoea and reduce the severity of the associated post-weaning growth check. However, this therapeutic zinc use has been attributed to environmental concerns and development of bacterial resistance, which has led to an EU ban, taking effect by 2022.
  • Orego-Stim has been shown to help maintain, and in some cases improve, piglet growth performance in replacement of therapeutic levels of zinc oxide.


  • Traditionally, zinc is added to piglet starter diets (commonly in the form of zinc oxide) at high levels in order to control post-weaning diarrhoea and achieve optimum piglet performance. However, the EU ban will result in a maximum content of zinc (<150ppm) in piglet diets and therefore potential alternatives must be found.
  • Orego-Stim is a high quality eubiotic containing 100% natural oregano oil composed of carvacrol and thymol. These essential oils are proven to act in an immunomodulatory manner, along with demonstrated antioxidant properties whilst promoting a healthy appetite, improved gut health and performance.
  • The trial was undertaken in order to determine if Orego-Stim could be used as a suitable alternative to zinc oxide in piglet diets post-weaning.



An independant trial was conducted on a commercial unit in Denmark where newly weaned piglets were allocated to one of two trials for either 21 or 49 days. In both trials piglets were either fed a standard control diet with the addition of 2.5kg/t zinc oxide and 6kg/t benzoic acid or an alternative diet substituting zinc oxide and benzoic acid with Orego-Stim (OS) at 0.5kg/t. Average piglet start weight, end weight, feed intake and liveability were measured, allowing average daily gain (ADG), feed conversion ratio (FCR) and mortality to be determined for piglets up to both 21 and 49 days post-weaning.  Cost per kg of growth was also calculated.


  • Piglets fed diets containing Orego-Stim performed as well as, if not numerically better, than piglets fed diets containing both benzoic acid and zinc oxide up to either 21 and 49 days post-weaning.
  • The average piglet cost per kg gained when using Orego-Stim in replacement of both zinc oxide and benzoic acid was lower for both trial durations (with a difference of £0.17).
  • Therefore, Orego-Stim could provide an effective alternative to zinc oxide, whilst maintaining piglet performance and improving profitability.