Effects of chitosan- and alginate-encapsulated olive leaf extract on performance, selected blood parameters, and antioxidant activity in broiler diets

This study was conducted to determine the effects of supplementing broiler diets with olive leaf extract (OLE) and chitosan- and alginate-coated olive leaf extract (C-OLE) on performance; internal organ weights; selected blood serum biochemical values; breast- and thigh-meat pH; breast-meat MDA values; intestinal pH; tibia and femur morphometric characteristics (width, length, and weight); and dry matter levels and ammonia concentrations in litter and feces. In this study, OLE (1.5%) was subsequently encapsulated with alginate (1%) and chitosan (1%). After drying, the alginate- and chitosan-coated olive leaf extract was added to broiler rations at 1%. The research was conducted over 37 days with 105 one-day-old male broiler chicks. The chicks were randomly allocated to three groups: one control group and two treatment groups. The control group received a basal diet without supplementation. In contrast, one treatment group was fed a diet supplemented with OLE, and the other was fed a diet supplemented with C-OLE; each supplement contained 125 mg/kg oleuropein. On day 37, statistically significant differences were observed between the treatment groups and the control group in body weight, body weight gain, feed intake, feed conversion rate, the European Production Efficiency Factor (EPEF), and some organ weights (P<0.05). In conclusion, encapsulated olive leaf extract containing 125 mg/kg oleuropein may improve the bioavailability of phenolic compounds and may represents a promising natural feed additive for broiler production.