Effects of Oregano Essential Oil Supplementation to Diets of Broiler Chicks with Delayed Feeding After Hatching. Morphological Development of Small Intestine Segments

The study aimed to investigate the effects of dietary supplementation of oregano essential oil (OEO) on the morphological development of small intestine of broilers with different feeding times (immediate, 24, 48 or 72 h posthatching delayed feeding) from d 0 to 14. The diets were supplemented with: no, 250 or 500 mg/kg of the OEO (OEO250 and OEO500, respectively). Fasting for 72 h significantly increased the weight and length of small intestine segments of broilers on d 14. The OEO250 and OEO500 significantly increased the jejunum villus height of chickens fed immediately and the duodenum villus height of broilers fasted for 48 h. The duodenum villus surface area of chickens fasted for 48 h and the ileum villus surface area of broilers fasted for 24 h were significantly increased by the OEO250. The OEO500 significantly enhanced the duodenum villus surface area of broilers fasted for 24 h and their ileum villus surface area fasted for 48 h. The crypt depths of small intestine segments of broilers fasted for 72 h were significantly reduced by OEO250 and OEO500. In conclusion, the dose of phenolic compounds in OEO reaching the small intestine might be enough for protecting the intestinal epithelial cells from damages of toxins and for removing the negative effects of delayed feeding on the morphological development of all the small intestine segments of broiler chicks on d 14.