Effect Of Zinc Bearing Palygorskite Supplementation On The Meat Quality,Tissue Mineral Element Accumulation And Antioxidant Function Of Broilers

Zinc(Zn)bearing palygorskite(ZnPal)can promote growth performance and intestinal morphological development,enhance activities of digestive enzymes,and improve immunity of broilers.However,little information is available regarding for the effect of ZnPal supplementation on meat quality,tissues metal element deposition or antioxidant function.This study selected AA broiler as the experimental animal to evaluate the effect of ZnPal on meat quality,mineral content and antioxidant capacity by supplementing the basal diet with different level of ZnPal,aiming to provide theoretical reference for the widely using of ZnPal in broiler industry.The study was divided into the following three parts:The first experiment was undertaken to study the influence of ZnPal inclusion on the growth performance,carcass trait,and meat quality of broilers.240 one-day-old Arbor Acres broiler chicks were randomly divided into 5 dietary treatments consisted of 6 replicates of 8 chicks.Each Birds in the 5 treatments were fed a basal diet supplemented with 0(control group),20,40,60,and 80 mg/kg Zn as ZnPal for 42 d,respectively.Compared with the control group,the eviscerated yield(quadratic,P = 0.010),and breast muscle yield(linear,P = 0.024;quadratic,P = 0.011)were significantly increased by the supplementation of ZnPal.Similarly,the addition of ZnPal to the diets of broilers also increased the fat deposition in the thigh muscle(linear,P = 0.002),but reduced the cooking loss of the breast(linear,P = 0.013)and thigh muscles(linear,P = 0.029;quadratic,P =0.034).The second experiment was conducted to study the effect of ZnPal inclusion on the mineral elements accumulation in the tissues(liver,pancreas,and breast and thigh muscles)of broilers.The experimental design was the same to that in the first trial.The addition of different dosage of Zn as ZnPal significantly increased the hepatic Zn and(linear,P<0.01)and magnesium(Mg)(linear,P<0.01)contents at 21 d,and enhanced the Mg content in the breast muscle(linear,P = 0.002)and pancreas(linear,P = 0.023;quadratic,P = 0.004)at 42 d.Similarly,ZnPal supplementation elevated the 21 d pancreas iron(Fe)content(linear,P = 0.010;quadratic,P = 0.033)and the 42 d hepatic(quadratic,P = 0.031)Fe content,but decreased 42 d thigh copper(Cu)accumulation(linear,P = 0.011).The accumulation of chromium(Cr)in the 21 d pancreas(linear,P = 0.001),breast muscle(linear,P = 0.039;quadratic,P = 0.016),and thigh muscle(linear,P<0.01;quadratic,P =0.003)was decreased by ZnPal inclusion.Meanwhile,the ZnPal treatments lowered the lead(Pb)concentration in the thigh muscle(linear,P<0.01;quadratic,P<0.01).The third trial was aimed to evaluate the effect of ZnPal supplementation on the antioxidant status in the tissues(liver,pancreas,and breast and thigh muscles)of broilers.The experimental design was the same to that in the first experiment.The results showed that the addition of different dosage of Zn as ZnPal significantly reduced the 21 d serum malondialdehyde(MDA)content(linear,P = 0.007),increased the 42 d serum total superoxide dismutase(T-SOD)activity(quadratic,P = 0.001).The 42 d hepatic copper zinc superoxide dismutase(Cu/Zn SOD)activity(quadratic,P = 0.001)and T-SOD activity at both 21 d(linear,P = 0.001)and 42 d(quadratic,P = 0.022)were enhanced by ZnPal supplementation.Similiarly,the ZnPal addition significantly elevated the jejunal mucosal T-SOD(linear,P = 0.036;quadratic,P = 0.005)and Cu/Zn SOD activities(linear,P =0.012),and the ileal mucosal Cu/Zn SOD activity(linear,P = 0.001)at 21 d.Meanwhile,ZnPal incorporation significantly increased the activities of T-SOD(linear,P = 0.042)and Cu/Zn SOD(quadratic,P = 0.010)in the jejunal mucosa,whereas reduced MDA content(linear,P = 0.020;quadratic,P=0.017)in the thigh muscle at 42 d.