Abstract
Due to its beneficial components, such as glycyrrhizin, licorice is regarded a medicinal and fragrant plant. This research was designed to investigate the efficacy of licorice essential oil as an alternative to chemical antibiotics on broiler production, carcass features, cellular and humoral safety, and numerous biochemical variables in broiler blood serum. A total of 160 day-old broiler chicks were assigned to four treatment groups using a totally randomized approach. Each treatment consisted of 4 replicates, with 10 chicks in each replication. The experimental treatments included a control group, a group receiving an elemental diet containing 0.1% licorice essential oil, a group receiving an elemental diet containing 0.2% licorice essential oil, and a group receiving an elemental diet containing 0.3% licorice essential oil. Broilers had ad libitum access to feed and water in accordance with a three-phase feeding schedule consisting of a starter, grower, and finisher diet. There was no statistically significant difference (P>0.05) in body weight, feed intake, or feed conversion ratio between birds given the control or essential oil licorice at various stages of the experiment. However, birds receiving 0.1% licorice essential oil had a lower gallbladder relative weight and 0.3% licorice essential oil had less abdominal fat than the control group (P<0.05). Blood glucose, cholesterol, and LDL concentrations all fell considerably in licorice essential oil-treated birds relative to controls (P<0.05). The cellular immune response of birds fed licorice-containing diets did not differ from that of control birds (P>0.05), however there was a significant difference in the humoral immune response at 0.1% licorice essential oil compared to the control group (P<0.05). In overall, the results of this experiment demonstrated that incorporating licorice essential oil into a bird's diet improves its health and safety.