Effects of gallus epidermal growth factor（gEGF）from chicken embryos on growth performance, serum biochemical indices, immune function and intestinal morphology of broilers

Abstract

We aimed to investigate the effects of dietary supplementation with gallus epidermal growth factor (gEGF) from chicken embryos on growth performance, immunity, and intestinal morphology in broilers. 480 1-day-old AA broilers were randomly divided into 5 groups with 6 replicates of 16 chicks each. The control group was fed basal diet and other treatment diets were supplemented with 4, 6, 8, 12 ng/kg gEGF, respectively. The whole experiment lasted for 42 d. Broilers were harvested at the end of the experiment, and spleen, thymus, bursa, serum samples and small intestine were collected. Results showed that average daily growth (ADG) of 1–21d at the 4, 6 and 12 ng/kg groups were significantly increased (p < .05); ADG (22–42d, 1–42d) and ADFI of 1–42d at the 4 ng/kg group were also increased (p < .05). Dietary gEGF at 4 and 6 ng/kg groups improved catalase (CAT) activity, and total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-PX) activity were significantly increased (p < .05) while malondialdehyde (MDA) concentration significantly decreased (p < .05) at 12 ng/kg group. Compared with the control group, the thymus index of the 8 ng/kg group was significantly increased (p < .05). Dietary gEGF at less than or equal to 8 ng/kg level improved Bursa of Fabricius (BF) index (p < .05). Moreover, at the 8 ng/kg group, serum immunoglobulin A (IgA) and immunoglobulin M (IgM) concentrations were significantly higher (p < .05) than in the control group. Intestinal development was enhanced by gEGF inclusion. These findings demonstrated that dietary gEGF supplementation improved growth performance, antioxidant capacity, immunity and the development of the intestine in broilers. And the suitable dosage of gEGF in broiler diets is 8 ng/kg. The gEGF has the potential to be used as a feed additive in broilers. Highlights 4 ng/kg gEGF dietary supplementation had a positive effect (P < 0.05) on growth performance of broilers. Antioxidant capacity (T-AOC, GSH-PX, CAT) of serum significantly increased, and MDA decreased at 12 ng/kg group. Dietary gEGF exhibited positive influence on immunity of broilers. Dietary gEGF improved the development of small intestinal by increasing the villus height and reducing the crypt depth of small intestine in broilers.