Effect of dietary oregano essential oil on the growth, meat quality, selenium distribution, and serum biochemical traits of pigs

Abstract

Natural substances of plant origin play an important role in the protection of animal health and improvement of the quality and health safety of food products of animal origin. The research was carried out to determine the effect of oregano essential oil used as a feed additive for pigs on growth performance, meat quality and chemical composition, the level of selenium in pig tissues, and selected serum biochemical indicators. The experiment was conducted on 40 fatteners of the 990 Polish Synthetic Line. The animals were divided into two groups (20 animals in each) with an equal share of gilts and barrows. The pigs in the control group (CG) received a basal diet, while the pigs in the experimental group (OG) received the same diet supplemented with 300 mg·kg-1 Ecodiar®, containing 5% natural oregano oil (Origanum vulgare ssp. hirtum). The study did not show a significant effect of the preparation containing oregano oil on the body weight of fattening pigs, their growth rate, or feed intake and utilization. Chemical analysis showed that pigs receiving the oregano oil supplement had significantly higher (P ≤ 0,05) content of dry matter in the longissimus dorsi (LD) muscle. The LD muscle colour assessment showed that supplementation of the diet with oregano oil during the fattening period had a significant effect on the yellow colour component of meat (higher b* values; P ≤ 0,05). Supplementation with oregano oil significantly reduced the serum triglyceride concentration (P ≤ 0,05). The addition of oregano oil to the feed does not affect the fattening and carcass characteristics of pigs; however, it may have a beneficial effect on some meat quality characteristics of fatteners.