Effects of free and nanoencapsulated garlic essential oil on growth performance and immune functions in broiler chickens

Abstract The aim of this research was to determine the effect of free and nanoencapsulated garlic essential oil (GEO) on performance, serum biochemistry, and immune functions. Broiler chickens (900 males 1‐day‐old, Ross 308) were randomly assigned to six treatment diets (0, 75, or 150 mg/kg free GEO and 0 [containing chitosan], 75, or 150 mg/kg nanoencapsulated GEO) in a 2 × 3 factorial arrangement of treatments. The inclusion of nanoencapsulated GEO with a concentration of 75 mg/kg significantly increased the growth performance ( p < 0.05) of the birds fed the diet containing free GEO (75 mg/kg). Also, GEO nanocapsules significantly reduced serum total cholesterol and low‐density lipoprotein cholesterol (LDL‐C) compared to the control diet ( p < 0.05) (42 days), sheep red blood cell (SRBC) antibody titer (35 and 42 days), heterophilus (H): lymphocyte (L), and H ratio, 2,4‐dinitrochlorobenzene (DNCB) (42 days) ( p < 0.05). In conclusion, the findings show that the amount of 75 (mg/kg) of the nanoencapsulated GEO, compared to the free GEO, causes more growth performance and strengthens the immune system of broiler chickens.