Dietary oregano and thyme bioactive lipid compounds enhance laying performance, egg quality, antioxidant capacity, and blood biochemistry in Hy-Line Brown hens

The impacts of bioactive lipid compounds of oregano (OBLC) and thyme (TBLC) or their combinations (MIX) on performance, egg quality, antioxidant status, and blood biochemistry of laying hens throughout the late laying period were evaluated. A total of two hundred 64–week-old Hy-Line Brown laying chickens (mean body weight 1750 ± 56 g) were allocated at random to four experimental treatments: the basal control diet or the basal diet supplemented with 150 mg OBLC, 150 mg TBLC, or a mix of OBLC (150 mg/kg) and TBLC (150 mg/kg) over an 8-week period. Throughout the trials, dietary OBLC, TBLC, and their combination increased egg production and egg mass but decreased feed conversion ratio (p < 0.05). Dietary supplementation with OBLC and TBLC and their combination resulted in higher eggshell ratio, thickness, and strength (p < 0.05) than the control group. OBLC, TBLC, and their combination significantly increased albumen height and the Haugh unit. Notably, serum levels of calcium, phosphorus, total antioxidants, and superoxide dismutase significantly increased (p < 0.01) by OBLC, TBLC, and their combination. Supplementation of OBLC, TBLC, and their combination significantly (p < 0.05) reduced serum levels of total cholesterol, triglycerides, creatinine, uric acid, aspartate aminotransferase, and alanine aminotransferase compared to control. It can be postulated that 150 mg/kg OBLC, TBLC, and their combination can be used as efficient feed additives to enhance overall performances, antioxidants, and the health status of laying hen chickens in the late production period.