Effects Of Enteromorpha Prolifera Polysaccharide-zinc Complex On Oxidative Stress Response And Metal Element Deposition In Broilers

This experiment was conducted to investigate the effects of Enteromorpha prolifera polysaccharide-zinc(EP-Zn)complex on oxidative stress response and metal element deposition of broilers.A total of 240 healthy 7-day-old broiler chickens were randomly divided into 2 groups with 12 replicates per group and 10 broilers per replicate.The control group was fed a basal diet,and the experimental group was fed the diet supplemented with300 mg/kg EP-Zn.The experiment lasted for 33 days.The main results are as follows:1.Effects of EP-Zn on growth performance and serum biochemical indices of broilers(1)Compared with the control group,EP-Zn significantly increased the average daily gain and final body weight of broilers(P<0.05),suggesting an improvement in growth.(2)Besides,the serum index results showed that birds fed EP-Zn had significantly higher serum high-density lipoprotein(HDL)(P<0.05)levels than chickens in the control group.2.Effects of EP-Zn on antioxidant indices and relative expression levels of key antioxidant genes in broilers(1)Compared with the control group,EP-Zn significantly increased the activities of superoxide dismutase(SOD)and Cu-Zn superoxide dismutase(Cu-Zn SOD)in the serum(P< 0.05);total antioxidant capacity(T-AOC)activity of duodenal mucosa and glutathione peroxidase(GSH-Px)activity of jejunal mucosa,and reduce the MDA content in the ileal mucosa.In addition,the activities of T-AOC,GSH-Px and Cu-Zn SOD in the liver were significantly increased(P < 0.05)in the EP-Zn group.(2)Furthermore,q PCR results showed that dietary EP-Zn supplementation significantly upregulated c-Jun amino-terminal kinase 2(JNK2),superoxide dismutase 1(SOD1),glutathione peroxidase 1(GPX1),glutathione peroxidase 4(GPX4)m RNA levels in duodenal mucosa and p38 mitogen-activated protein kinase(p38 MAPK)levels in jejunal mucosa.Similarly,the relative m RNA expression levels of p38 MAPK,JNK2,SOD1,superoxide dismutase 2(SOD2),JNK2 and GPX1 in ileal mucosa were significantly up-regulated in the EP-Zn group than the control group.In addition,EP-Zn significantly upregulated the relative m RNA expression levels of kelch-like ECh-associated protein 1(Keap1),extracellular signalregulated protein kinase(ERK),p38 MAPK and SOD2 in the liver.In conclusion,EP-Zn may activate the antioxidant mechanism through JNK/p38 MAPK signaling pathway to regulate the expression of downstream antioxidant enzyme gene,thereby improving the antioxidant enzyme activity,affecting the redox state,and promoting the health of broilers.3.Effects of EP-Zn on metal element deposition in broilers(1)Compared with the control group,EP-Zn significantly increased the selenium contents in serum and liver(P<0.05),and significantly increased the selenium and manganese contents in liver and muscle of broilers(P<0.05).(2)EP-Zn supplementation significantly reduced the content of lead in the faeces of broilers(P<0.05).In conclusion,EP-Zn can regulate the metal element deposition in broilers,thereby reducing the emission of heavy metals,and the associated pollution to the ecological environment.