PERFORMANCE RESPONSES TO ESSENTIAL OILS IN PIGS

The use of essential oils has generated interest in recent years due to their wide range of active compounds with interesting properties (antibacterial, antioxidant, digestive, antifungal, etc.), as well as their good social acceptance.

Essential oils are secondary metabolites of plants that can contain between 20 to 60 different chemical components, each with its characteristic properties. Regarding its biological activity, EOs generally have two or three main compounds in high concentrations (15-70%) that determine their core biological properties (Burt et al. 2004 and Nampoothiri at al. 2012). However, some studies also indicate the importance of minor components and their synergistic effect with the main compounds.

Due to the great complexity of the biological activity, it is difficult to compare specific physiological actions between different EOs (with different botanical species, concentrations, doses, etc.). Most of the available studies are about additives that include mixtures of various active compounds and focus on their effects on performance parameters.

In this context, several authors have reviewed the available data on the performance responses of different EOs additives on the market. These reviews report average piglet performance improvements about 8.6% in weight gain, 4.5% in feed intake, and 2.8% in feed conversion ratio (Zeng et al. 2015 and Windisch et al. 2008).

Additives based on EOs are currently showing positive results. Available studies on the use of essential oils as feed additives in swine show how they are achieving consistent performance improvements, especially in piglets after weaning. However, there is also variability in results between different types of EOs as well as between different trials of the same product. These differences could be explained by the specific biological actions of the different EOs blends, as well as the usual variations due to trial conditions (environment, management, diets, etc.).

We can conclude that essential oils are further to consolidate themselves as one of the alternatives to sustain high performance in a more sustainable and safer pig production.