Effect of aqueous-alcoholic extract of Hibiscus sabdariffa calyx and leaf calyx and leaf on performance, egg quality, immune system and antioxidant balance of laying hens.

This experiment was conducted to obtain information on how aqueous-alcoholic extractof H. sabdariffa plant can affect laying hen performance, egg quality, immune system and antioxidant balance during thermo-neutrals conditions. Two hundred hens (23-wk-old) were divided into 5 experimental treatments with 4 replicates each, 10 white-egg Hy-Line (W36) hens per cage. Treatment 1 (control) birds were fed with a corn and soybean meal-based diet without extract, whereas treatments 2 and 3 received, 300 and 700 mg/kg of H. sabdariffa leaf extract (HSLE) and treatments 4 and 5, received 300 and 700 mg/kg of H. sabdariffa calyx extract (HSCE), respectively. The weekly recorded performance data included egg production, feed intake, egg mass and feed conversion ratio. The egg quality parameters were evaluated at each 28 days of the experimental periods. Two hens from each replicate were selected and the blood was gathered to determine the immune system and plasma malondialdehyde (MDA). Also, two egg yolks from each replicate were used to investigated yolk MDA, cholesterol and triglyceride. Comparing the results with the control showed, HSCE at 700 mg/kg promoted laying rate during peak production (P<0.05) up to 8%. However, antioxidant balance and immune function did not differ between treatment groups. Eggshell strength, eggshell thickness, eggshell weight and egg-shape index were affected by treatments (P<0.05). Hens receiving 700 mg/kg of HSLE significantly decreased yolk cholesterol (P<0.05) compared to the control group (44.74 vs. 47.67). The results suggest that the H. sabdariffa can improve laying performance, egg qualitative characteristics and reduce egg yolk cholesterol during peak production period. The beneficial effects of the H. sabdariffa should be further studied in commercial production conditions.