The effects of supplemented dietary of alfa- tocopherol acetat, carvacrol, carnosic acid in laying hens on egg production, egg quality and blood parameters and under high temperature

The present study was conducted to evaluate whether alfa-tocopherol acetatat, carvacrol and carnosic acid supplemented dietary would affect laying performance, egg quality, antioxidant structure, oxidative stres and blood parameters of Brown layers under high temperature.Fortyfive weeks old layers were divided into 4 groups of similar mean weight, comprising 18 birds each. The birds were fed standard layer diets and 200 mg/kg diet alpha- tocopherol acetate, carvacrol and carnosic acid supplemented diets for 8 weeks period. The birds were housed in individual cages in a complete randomized design. During the study, a 16:8 hours light:dark photoperiod (8 hours 34-36 ?C at light period and 16 hours 22-24?C ) was employed, feed and water were given ad libitum. Laying performance was assessed by recording feed intake, egg weight, egg production daily; egg quality weekly and blood parameters (glucose, cholesterol, triglyceride level, lipid peroxidation, total antioxidant and calcium) biweekly. The results showed that alpha- tocopherol acetate, carvacrol and carnosic acid supplementation did not have significant (P>0.05) effects on feed intake, egg weight, egg mass, body weight and blood parameters. However, dietary supplementation of carvacrol improved feed conversion efficiency (P<0.05) and egg quality parametres.The results obtained in the experiment suggest that providing supplemented dietary carvacrol could protect egg quality parameters under heat stress.