Inclusion of essential oil of oregano enhances intestinal morphology in broiler

Abstract

Antibiotics have been used as additives in animal feed, especially in broilers worldwide, for therapeutic purposes and as growth promoters (APC); However, the growing concern over the proliferation of resistant microorganisms has led to the prohibition of the use of antibiotics in animal feed in many countries. As an alternative, the use of extracts derived from aromatic plants, called “essential oils” has been proposed. Therefore, the objective of this work was to evaluate the effect of the inclusion of three levels of Oregano Essential Oil (AEO), (Lippia origanoides), on the growth and digestive morphology in broilers of the Cobb500 genetic line. We used 200 male chicks one-day old, housed in pens on the floor. The animals were randomized to one of five diets: commercial diet with and without antibiotic; this last one added with different levels of AEO (0ppm, 75ppm, 100ppm or 200ppm AEO). The birds were sacrificed on days 14, 28 and 42 of life, and the small intestine was extracted, from which portions of the duodenum, jejunum and ileum were taken for histological evaluation. A randomized block statistical design was performed in an array of divided plots, where the animals were randomized to one of 15 treatments (5 diets for 3 ages). For intestinal villi a significant increase in length and width was found, and for intestinal crypts a significant decrease in depth and width was found; both parameters in favor of the diet with greater inclusion of AEO (200ppm AEO) (P <0.01). The addition of 200ppm of AEO in the feed of broilers increases the length and width of the villi, and decreases the depth and width of the crypts at the intestinal level, increasing the absorption capacity of the intestine of the birds. Therefore, the AEO is constituted as a nutritional growth promoter of plant origin, positively affecting the intestinal morphology during the meat production cycle with broiler chickens.